1
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Root SH, Matthews BG, Torreggiani E, Aguila HL, Kalajzic I. Hematopoietic and stromal DMP1-Cre labeled cells form a unique niche in the bone marrow. Sci Rep 2023; 13:22403. [PMID: 38104230 PMCID: PMC10725438 DOI: 10.1038/s41598-023-49713-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2023] [Accepted: 12/11/2023] [Indexed: 12/19/2023] Open
Abstract
Skeletogenesis and hematopoiesis are interdependent. Niches form between cells of both lineages where microenvironmental cues support specific lineage commitment. Because of the complex topography of bone marrow (BM), the identity and function of cells within specialized niches has not been fully elucidated. Dentin Matrix Protein 1 (DMP1)-Cre mice have been utilized in bone studies as mature osteoblasts and osteocytes express DMP1. DMP1 has been identified in CXCL12+ cells and an undefined CD45+ population. We crossed DMP1-Cre with Ai9 reporter mice and analyzed the tdTomato+ (tdT+) population in BM and secondary hematopoietic organs. CD45+tdT+ express myeloid markers including CD11b and are established early in ontogeny. CD45+tdT+ cells phagocytose, respond to LPS and are radioresistant. Depletion of macrophages caused a significant decrease in tdT+CD11b+ myeloid populations. A subset of CD45+tdT+ cells may be erythroid island macrophages (EIM) which are depleted after G-CSF treatment. tdT+CXCL12+ cells are in direct contact with F4/80 macrophages, express RANKL and form a niche with B220+ B cells. A population of resident cells within the thymus are tdT+ and express myeloid markers and RANKL. In conclusion, in addition to targeting osteoblast/osteocytes, DMP1-Cre labels unique cell populations of macrophage and stromal cells within BM and thymus niches and expresses key microenvironmental factors.
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Affiliation(s)
- Sierra H Root
- Center for Regenerative Medicine and Skeletal Development, MC 3705, School of Dental Medicine, UConn Health, 263 Farmington Ave, Farmington, CT, 06030, USA.
- Division of Pediatric Dentistry, MC1610, School of Dental Medicine, UConn Health, 263 Farmington Ave, Farmington, CT, 06030, USA.
| | - Brya G Matthews
- Center for Regenerative Medicine and Skeletal Development, MC 3705, School of Dental Medicine, UConn Health, 263 Farmington Ave, Farmington, CT, 06030, USA
- Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand
| | - Elena Torreggiani
- Center for Regenerative Medicine and Skeletal Development, MC 3705, School of Dental Medicine, UConn Health, 263 Farmington Ave, Farmington, CT, 06030, USA
| | | | - Ivo Kalajzic
- Center for Regenerative Medicine and Skeletal Development, MC 3705, School of Dental Medicine, UConn Health, 263 Farmington Ave, Farmington, CT, 06030, USA.
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2
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Cao Y, Kalajzic I, Matthews BG. CD51 labels periosteal injury-responsive osteoprogenitors. Front Physiol 2023; 14:1231352. [PMID: 37731543 PMCID: PMC10507171 DOI: 10.3389/fphys.2023.1231352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 08/22/2023] [Indexed: 09/22/2023] Open
Abstract
The periosteum is a critical source of skeletal stem and progenitor cells (SSPCs) that form callus tissue in response to injury. There is yet to be a consensus on how to identify SSPCs in the adult periosteum. The aim of this study was to understand how potential murine periosteal SSPC populations behave in vivo and in response to injury. We evaluated the in vivo differentiation potential of Sca1-CD51+ and Sca1+CD51+ cells following transplantation. In vitro, the Sca1+CD51+ population appears to be more primitive multipotent cells, but after transplantation, Sca1-CD51+ cells showed superior engraftment, expansion, and differentiation into chondrocytes and osteoblasts. Despite representing a clear population with flow cytometry, we identified very few Sca1+CD51+ cells histologically. Using a periosteal scratch injury model, we successfully mimicked the endochondral-like healing process seen in unstable fractures, including the expansion and osteochondral differentiation of αSMA+ cells following injury. CD51+ cells were present in the cambium layer of resting periosteum and expanded following injury. Sca1+CD51- cells were mainly localized in the outer periosteal layer. We found that injury increased colony-forming unit fibroblast (CFU-F) formation in the periosteum and led to rapid expansion of CD90+ cells. Several other populations, including Sca1-CD51+ and CD34+ cells, were expanded by day 7. Mice with enhanced fracture healing due to elevated Notch signaling mediated by NICD1 overexpression showed significant expansion of CD51+ and CD34hi cells in the early stages of healing, suggesting these populations contribute to more rapid healing. In conclusion, we demonstrate that periosteal injury leads to the expansion of various SSPC populations, but further studies are required to confirm their lineage hierarchy in the adult skeletal system. Our data indicate that CD51+ skeletal progenitor cells are injury-responsive and show good engraftment and differentiation potential upon transplantation.
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Affiliation(s)
- Ye Cao
- Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand
| | - Ivo Kalajzic
- Center for Regenerative Medicine and Skeletal Development, School of Dental Medicine, UConn Health, Farmington, CT, United States
| | - Brya G. Matthews
- Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand
- Center for Regenerative Medicine and Skeletal Development, School of Dental Medicine, UConn Health, Farmington, CT, United States
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3
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Affiliation(s)
- Lilian I Plotkin
- Department of Anatomy, Cell Biology & Physiology, Indiana University School of Medicine, Roudebush Veterans Administration Medical Center, Indiana Center for Musculoskeletal Health, Indianapolis, IN 46202, USA.
| | - Ivo Kalajzic
- Center for Regenerative Medicine and Skeletal Development, UConn Health, Farmington, CT 06032, USA.
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4
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Abdulmalik S, Gallo J, Nip J, Katebifar S, Arul M, Lebaschi A, Munch LN, Bartly JM, Choudhary S, Kalajzic I, Banasavadi-Siddegowdae YK, Nukavarapu SP, Kumbar SG. Nanofiber matrix formulations for the delivery of Exendin-4 for tendon regeneration: In vitro and in vivo assessment. Bioact Mater 2023; 25:42-60. [PMID: 36733930 PMCID: PMC9876843 DOI: 10.1016/j.bioactmat.2023.01.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 01/16/2023] [Accepted: 01/16/2023] [Indexed: 01/22/2023] Open
Abstract
Tendon and ligament injuries are the most common musculoskeletal injuries, which not only impact the quality of life but result in a massive economic burden. Surgical interventions for tendon/ligament injuries utilize biological and/or engineered grafts to reconstruct damaged tissue, but these have limitations. Engineered matrices confer superior physicochemical properties over biological grafts but lack desirable bioactivity to promote tissue healing. While incorporating drugs can enhance bioactivity, large matrix surface areas and hydrophobicity can lead to uncontrolled burst release and/or incomplete release due to binding. To overcome these limitations, we evaluated the delivery of a peptide growth factor (exendin-4; Ex-4) using an enhanced nanofiber matrix in a tendon injury model. To overcome drug surface binding due to matrix hydrophobicity of poly(caprolactone) (PCL)-which would be expected to enhance cell-material interactions-we blended PCL and cellulose acetate (CA) and electrospun nanofiber matrices with fiber diameters ranging from 600 to 1000 nm. To avoid burst release and protect the drug, we encapsulated Ex-4 in the open lumen of halloysite nanotubes (HNTs), sealed the HNT tube endings with a polymer blend, and mixed Ex-4-loaded HNTs into the polymer mixture before electrospinning. This reduced burst release from ∼75% to ∼40%, but did not alter matrix morphology, fiber diameter, or tensile properties. We evaluated the bioactivity of the Ex-4 nanofiber formulation by culturing human mesenchymal stem cells (hMSCs) on matrix surfaces for 21 days and measuring tenogenic differentiation, compared with nanofiber matrices in basal media alone. Strikingly, we observed that Ex-4 nanofiber matrices accelerated the hMSC proliferation rate and elevated levels of sulfated glycosaminoglycan, tendon-related genes (Scx, Mkx, and Tnmd), and ECM-related genes (Col-I, Col-III, and Dcn), compared to control. We then assessed the safety and efficacy of Ex-4 nanofiber matrices in a full-thickness rat Achilles tendon defect with histology, marker expression, functional walking track analysis, and mechanical testing. Our analysis confirmed that Ex-4 nanofiber matrices enhanced tendon healing and reduced fibrocartilage formation versus nanofiber matrices alone. These findings implicate Ex-4 as a potentially valuable tool for tendon tissue engineering.
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Affiliation(s)
- Sama Abdulmalik
- Department of Orthopedic Surgery, University of Connecticut Health, Farmington, CT, USA
- Department of Biomedical Engineering, University of Connecticut, Storrs, CT, USA
| | - Jack Gallo
- Department of Orthopedic Surgery, University of Connecticut Health, Farmington, CT, USA
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, CT, USA
| | - Jonathan Nip
- Department of Orthopedic Surgery, University of Connecticut Health, Farmington, CT, USA
- Department of Biomedical Engineering, University of Connecticut, Storrs, CT, USA
| | - Sara Katebifar
- Department of Orthopedic Surgery, University of Connecticut Health, Farmington, CT, USA
- Department of Biomedical Engineering, University of Connecticut, Storrs, CT, USA
| | - Michael Arul
- Department of Orthopedic Surgery, University of Connecticut Health, Farmington, CT, USA
| | - Amir Lebaschi
- Department of Orthopedic Surgery, University of Connecticut Health, Farmington, CT, USA
| | - Lucas N. Munch
- Department of Orthopedic Surgery, University of Connecticut Health, Farmington, CT, USA
| | - Jenna M. Bartly
- Department of Immunology, Center on Aging, University of Connecticut Health, Farmington, CT, USA
| | - Shilpa Choudhary
- Department of Orthopedic Surgery, University of Connecticut Health, Farmington, CT, USA
| | - Ivo Kalajzic
- Department of Reconstructive Sciences, University of Connecticut Health, Farmington, CT, USA
| | | | - Syam P. Nukavarapu
- Department of Orthopedic Surgery, University of Connecticut Health, Farmington, CT, USA
- Department of Biomedical Engineering, University of Connecticut, Storrs, CT, USA
- Department of Materials Science and Engineering, University of Connecticut, Storrs, CT, USA
| | - Sangamesh G. Kumbar
- Department of Orthopedic Surgery, University of Connecticut Health, Farmington, CT, USA
- Department of Biomedical Engineering, University of Connecticut, Storrs, CT, USA
- Department of Materials Science and Engineering, University of Connecticut, Storrs, CT, USA
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5
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Wee NKY, Novak S, Ghosh D, Root SH, Dickerson IM, Kalajzic I. Inhibition of CGRP signaling impairs fracture healing in mice. J Orthop Res 2023; 41:1228-1239. [PMID: 36281531 PMCID: PMC10123175 DOI: 10.1002/jor.25474] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 09/06/2022] [Accepted: 10/18/2022] [Indexed: 02/04/2023]
Abstract
Calcitonin gene-related peptide (CGRP) is a neuropeptide produced by sensory nerves and functions as a pain sensor. It acts by binding to the calcitonin-like receptor (CLR, protein; Calcrl, gene). CGRP inhibition has been recently introduced as therapeutic treatment of migraine-associated pain. Previous studies have shown that CGRP stimulates bone formation. The aim of our study is to determine whether the inhibition of CGRP signaling negatively impacted fracture healing. Using α-smooth muscle actin (αSMA) Cre animals crossed with Ai9 reporter mice, we showed that CGRP-expressing nerves are near αSMA + cells in the periosteum. In vitro experiments revealed that periosteal cells express Calcrl and receptor activity modifying protein 1; and CGRP stimulation increased periosteal cell proliferation. Using a tamoxifen-inducible model αSMACre/CLRfl/fl , we targeted the deletion of CLR to periosteal progenitor cells and examined fracture healing. Microcomputed tomography of fractured femurs showed a reduction in bone mass in αSMACre+/CLRfl/fl female mice relative to controls and callus volume in males. Pharmacological CGRP-CLR inhibition was achieved by subcutaneous delivery of customized pellets with small molecule inhibitor olcegepant (BIBN-4096) at a dose of 10 μg/day. BIBN-4096-treated C57BL/6J mice had a higher latency toward thermal nociception than placebo-treated mice, indicating impaired sensory function through CGRP inhibition. CGRP inhibition also resulted in reduced callus volume, bone mass, and bone strength compared to placebo controls. These results indicate that inhibiting CGRP by deleting CLR or by using BIBN-4096, contributes to delayed bone healing.
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Affiliation(s)
- Natalie KY Wee
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, CT 06030, USA
- Bone Cell Biology and Disease Unit, St Vincent’s Institute of Medical Research, Fitzroy, VIC 3065, Australia
| | - Sanja Novak
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, CT 06030, USA
| | - Debolina Ghosh
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, CT 06030, USA
| | - Sierra H Root
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, CT 06030, USA
| | - Ian M Dickerson
- Department of Neuroscience, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Ivo Kalajzic
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, CT 06030, USA
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6
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Root SH, Vrhovac Madunic I, Kronenberg MS, Cao Y, Novak S, Kalajzic I. Lineage Tracing of RGS5-CreER-Labeled Cells in Long Bones During Homeostasis and Injury. Stem Cells 2023; 41:493-504. [PMID: 36888549 PMCID: PMC10183968 DOI: 10.1093/stmcls/sxad020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 02/21/2023] [Indexed: 03/09/2023]
Abstract
Regulator of G protein signaling 5 (RGS5) is a GTPase activator for heterotrimeric G-protein α-subunits, shown to be a marker of pericytes. Bone marrow stromal cell population (BMSCs) is heterogeneous. Populations of mesenchymal progenitors, cells supportive of hematopoiesis, and stromal cells regulating bone remodeling have been recently identified. Periosteal and bone marrow mesenchymal stem cells (MSCs) are participating in fracture healing, but it is difficult to distinguish the source of cells within the callus. Considering that perivascular cells exert osteoprogenitor potential, we generated an RGS5 transgenic mouse model (Rgs5-CreER) which when crossed with Ai9 reporter animals (Rgs5/Tomato), is suitable for lineage tracing during growth and post-injury. Flow cytometry analysis and histology confirmed the presence of Rgs5/Tomato+ cells within CD31+ endothelial, CD45+ hematopoietic, and CD31-CD45- mesenchymal/perivascular cells. A tamoxifen chase showed expansion of Rgs5/Tomato+ cells expressing osterix within the trabeculae positioned between mineralized matrix and vasculature. Long-term chase showed proportion of Rgs5/Tomato+ cells contributes to mature osteoblasts expressing osteocalcin. Following femoral fracture, Rgs5/Tomato+ cells are observed around newly formed bone within the BM cavity and expressed osterix and osteocalcin, while contribution within periosteum was low and limited to fibroblastic callus with very few positive chondrocytes. In addition, BM injury model confirmed that RGS5-Cre labels population of BMSCs expands during injury and participates in osteogenesis. Under homeostatic conditions, lineage-traced RGS5 cells within the trabecular area demonstrate osteoprogenitor capacity that in an injury model contributes to new bone formation primarily within the BM niche.
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Affiliation(s)
- Sierra H Root
- Center for Regenerative Medicine and Skeletal Development, UConn Health, Farmington, CT, USA
| | - Ivana Vrhovac Madunic
- Center for Regenerative Medicine and Skeletal Development, UConn Health, Farmington, CT, USA
| | - Mark S Kronenberg
- Center for Regenerative Medicine and Skeletal Development, UConn Health, Farmington, CT, USA
| | - Ye Cao
- Center for Regenerative Medicine and Skeletal Development, UConn Health, Farmington, CT, USA
| | - Sanja Novak
- Center for Regenerative Medicine and Skeletal Development, UConn Health, Farmington, CT, USA
| | - Ivo Kalajzic
- Center for Regenerative Medicine and Skeletal Development, UConn Health, Farmington, CT, USA
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7
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Doherty L, Wan M, Peterson A, Youngstrom DW, King JS, Kalajzic I, Hankenson KD, Sanjay A. Wnt-associated adult stem cell marker Lgr6 is required for osteogenesis and fracture healing. Bone 2023; 169:116681. [PMID: 36708855 PMCID: PMC10015414 DOI: 10.1016/j.bone.2023.116681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 01/18/2023] [Accepted: 01/20/2023] [Indexed: 01/26/2023]
Abstract
Despite the remarkable regenerative capacity of skeletal tissues, nonunion of bone and failure of fractures to heal properly presents a significant clinical concern. Stem and progenitor cells are present in bone and become activated following injury; thus, elucidating mechanisms that promote adult stem cell-mediated healing is important. Wnt-associated adult stem marker Lgr6 is implicated in the regeneration of tissues with well-defined stem cell niches in stem cell-reliant organs. Here, we demonstrate that Lgr6 is dynamically expressed in osteoprogenitors in response to fracture injury. We used an Lgr6-null mouse model and found that Lgr6 expression is necessary for maintaining bone volume and efficient postnatal bone regeneration in adult mice. Skeletal progenitors isolated from Lgr6-null mice have reduced colony-forming potential and reduced osteogenic differentiation capacity due to attenuated cWnt signaling. Lgr6-null mice consist of a lower proportion of self-renewing stem cells. In response to fracture injury, Lgr6-null mice have a deficiency in the proliferation of periosteal progenitors and reduced ALP activity. Further, analysis of the bone regeneration phase and remodeling phase of fracture healing in Lgr6-null mice showed impaired endochondral ossification and decreased mineralization. We propose that in contrast to not being required for successful skeletal development, Lgr6-positive cells have a direct role in endochondral bone repair.
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Affiliation(s)
- Laura Doherty
- Department of Orthopaedic Surgery, UConn Musculoskeletal Institute, School of Medicine, USA; School of Dental Medicine, UConn Health, Farmington, CT 06030, USA
| | - Matthew Wan
- Department of Orthopaedic Surgery, UConn Musculoskeletal Institute, School of Medicine, USA
| | - Anna Peterson
- Department of Orthopaedic Surgery, UConn Musculoskeletal Institute, School of Medicine, USA
| | - Daniel W Youngstrom
- Department of Orthopaedic Surgery, UConn Musculoskeletal Institute, School of Medicine, USA
| | - Justin S King
- Department of Orthopaedic Surgery, UConn Musculoskeletal Institute, School of Medicine, USA
| | - Ivo Kalajzic
- School of Dental Medicine, UConn Health, Farmington, CT 06030, USA; Department of Reconstructive Sciences, School of Dental Medicine, UConn Health, Farmington, CT 06030, USA
| | - Kurt D Hankenson
- Department of Orthopaedic Surgery, School of Medicine, University of Michigan, Ann Arbor, MI 48109, USA
| | - Archana Sanjay
- Department of Orthopaedic Surgery, UConn Musculoskeletal Institute, School of Medicine, USA.
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8
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Novak S, Madunic J, Shum L, Vucetic M, Wang X, Tanigawa H, Ghosh M, Sanjay A, Kalajzic I. PDGF inhibits BMP2-induced bone healing. NPJ Regen Med 2023; 8:3. [PMID: 36631491 PMCID: PMC9834334 DOI: 10.1038/s41536-023-00276-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Accepted: 01/03/2023] [Indexed: 01/13/2023] Open
Abstract
Bone regeneration depends on a pool of bone/cartilage stem/progenitor cells and signaling mechanisms regulating their differentiation. Using in vitro approach, we have shown that PDGF signaling through PDGFRβ inhibits BMP2-induced osteogenesis, and significantly attenuates expression of BMP2 target genes. We evaluated outcomes of treatment with two anabolic agents, PDGF and BMP2 using different bone healing models. Targeted deletion of PDGFRβ in αSMA osteoprogenitors, led to increased callus bone mass, resulting in improved biomechanical properties of fractures. In critical size bone defects BMP2 treatment increased proportion of osteoprogenitors, while the combined treatment of PDGF BB with BMP2 decreased progenitor number at the injury site. BMP2 treatment induced significant bone formation and increased number of osteoblasts, while in contrast combined treatment with PDGF BB decreased osteoblast numbers. This is in vivo study showing that PDGF inhibits BMP2-induced osteogenesis, but inhibiting PDGF signaling early in healing process does not improve BMP2-induced bone healing.
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Affiliation(s)
- Sanja Novak
- grid.208078.50000000419370394Center for Regenerative Medicine and Skeletal Development, UConn Health, Farmington, CT USA
| | - Josip Madunic
- grid.208078.50000000419370394Center for Regenerative Medicine and Skeletal Development, UConn Health, Farmington, CT USA ,grid.414681.e0000 0004 0452 3941Biochemistry and Organic Analytical Chemistry Unit, Institute for Medical Research and Occupational Health, Zagreb, Croatia
| | - Laura Shum
- grid.208078.50000000419370394Center for Regenerative Medicine and Skeletal Development, UConn Health, Farmington, CT USA
| | - Milan Vucetic
- grid.208078.50000000419370394Center for Regenerative Medicine and Skeletal Development, UConn Health, Farmington, CT USA
| | - Xi Wang
- grid.208078.50000000419370394Center for Regenerative Medicine and Skeletal Development, UConn Health, Farmington, CT USA
| | - Hitoshi Tanigawa
- grid.208078.50000000419370394Center for Regenerative Medicine and Skeletal Development, UConn Health, Farmington, CT USA
| | - Mallika Ghosh
- grid.208078.50000000419370394Center for Vascular Biology, UConn Health, Farmington, CT USA
| | - Archana Sanjay
- grid.208078.50000000419370394Department of Orthopeadic Surgery, UConn Health, Farmington, CT USA
| | - Ivo Kalajzic
- grid.208078.50000000419370394Center for Regenerative Medicine and Skeletal Development, UConn Health, Farmington, CT USA
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9
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Novak S, Kalajzic I. AcanCreER lacks specificity to chondrocytes and targets periosteal progenitors in the fractured callus. Bone 2023; 166:116599. [PMID: 36309308 PMCID: PMC9832919 DOI: 10.1016/j.bone.2022.116599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 10/19/2022] [Accepted: 10/24/2022] [Indexed: 11/06/2022]
Abstract
Aggrecan (Acan) is a large proteoglycan molecule constituting the extracellular matrix of cartilage, secreted by chondrocytes. To specifically target the chondrocyte lineage, researchers have widely used the AcanCreER mouse model. Evaluation of specificity and efficiency of recombination, requires Cre animals to be crossed with reporter mice. In order to accurately interpret data from Cre models, it is imperative to consider A) the amount of recombination occurring in cells/tissues that are not intended for targeting (i.e., non-specific expression), B) the efficiency of Cre recombination, which can depend on dose and duration of tamoxifen treatment, and C) the activation of CreER without tamoxifen induction, known as "Cre leakage." Using a highly sensitive reporter mouse (Ai9, tdTomato), we performed a comprehensive analysis of the AcanCreER system. Surprisingly, we observed expression in cells within the periosteum. These cells expand at a stage when chondrocytes are not yet present within the forming callus tissue (Acan/Ai9+ cells). In pulse-chase experiments, we confirmed that fibroblastic Acan/Ai9+ cells within the periosteum can directly give rise to osteoblasts. Our results show that Acan/Ai9+ is not specific for the chondrocyte lineage in the fracture callus or with the tibial holes. The expression of AcanCreER in periosteal progenitor cells complicates the interpretation of studies evaluating the transition of chondrocytes to osteoblasts (termed transdifferentiation). Awareness of these issues and the limitations of the system will lead to better data interpretation.
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Affiliation(s)
- Sanja Novak
- Department of Reconstructive Sciences, UConn Health, Farmington, CT, USA
| | - Ivo Kalajzic
- Department of Reconstructive Sciences, UConn Health, Farmington, CT, USA.
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10
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Thaler R, Khani F, Sturmlechner I, Dehghani SS, Denbeigh JM, Zhou X, Pichurin O, Dudakovic A, Jerez SS, Zhong J, Lee JH, Natarajan R, Kalajzic I, Jiang YH, Deyle DR, Paschalis EP, Misof BM, Ordog T, van Wijnen AJ. Vitamin C epigenetically controls osteogenesis and bone mineralization. Nat Commun 2022; 13:5883. [PMID: 36202795 PMCID: PMC9537512 DOI: 10.1038/s41467-022-32915-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 08/09/2022] [Indexed: 11/26/2022] Open
Abstract
Vitamin C deficiency disrupts the integrity of connective tissues including bone. For decades this function has been primarily attributed to Vitamin C as a cofactor for collagen maturation. Here, we demonstrate that Vitamin C epigenetically orchestrates osteogenic differentiation and function by modulating chromatin accessibility and priming transcriptional activity. Vitamin C regulates histone demethylation (H3K9me3 and H3K27me3) and promotes TET-mediated 5hmC DNA hydroxymethylation at promoters, enhancers and super-enhancers near bone-specific genes. This epigenetic circuit licenses osteoblastogenesis by permitting the expression of all major pro-osteogenic genes. Osteogenic cell differentiation is strictly and continuously dependent on Vitamin C, whereas Vitamin C is dispensable for adipogenesis. Importantly, deletion of 5hmC-writers, Tet1 and Tet2, in Vitamin C-sufficient murine bone causes severe skeletal defects which mimic bone phenotypes of Vitamin C-insufficient Gulo knockout mice, a model of Vitamin C deficiency and scurvy. Thus, Vitamin C's epigenetic functions are central to osteoblastogenesis and bone formation and may be leveraged to prevent common bone-degenerating conditions.
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Affiliation(s)
- Roman Thaler
- Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN, USA.
- Department of Biochemistry & Molecular Biology, Mayo Clinic, Rochester, MN, USA.
- Center for Regenerative Medicine, Mayo Clinic, Rochester, MN, USA.
| | - Farzaneh Khani
- Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN, USA
| | - Ines Sturmlechner
- Departments of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, MN, USA
| | | | - Janet M Denbeigh
- Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN, USA
| | - Xianhu Zhou
- Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN, USA
| | - Oksana Pichurin
- Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN, USA
| | - Amel Dudakovic
- Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN, USA
- Department of Biochemistry & Molecular Biology, Mayo Clinic, Rochester, MN, USA
| | - Sofia S Jerez
- Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN, USA
- Department of Biochemistry & Molecular Biology, Mayo Clinic, Rochester, MN, USA
| | - Jian Zhong
- Epigenomics Program, Center for Individualized Medicine, Mayo Clinic, Rochester, MN, USA
| | - Jeong-Heon Lee
- Department of Biochemistry & Molecular Biology, Mayo Clinic, Rochester, MN, USA
- Epigenomics Program, Center for Individualized Medicine, Mayo Clinic, Rochester, MN, USA
| | - Ramesh Natarajan
- Department of Internal Medicine, Virginia Commonwealth University, Richmond, VA, USA
| | - Ivo Kalajzic
- Department of Reconstructive Sciences, UConn Health, Farmington, CT, USA
| | - Yong-Hui Jiang
- Department of Genetics, Neuroscience, and Pediatrics, Yale University School of Medicine, New Haven, CT, USA
| | - David R Deyle
- Department of Clinical Genomics, Mayo Clinic, Rochester, MN, USA
| | - Eleftherios P Paschalis
- Ludwig Boltzmann Institute of Osteology at Hanusch Hospital of OEGK and AUVA Trauma Centre Meidling, 1st Med. Dept. Hanusch Hospital, Vienna, Austria
| | - Barbara M Misof
- Ludwig Boltzmann Institute of Osteology at Hanusch Hospital of OEGK and AUVA Trauma Centre Meidling, 1st Med. Dept. Hanusch Hospital, Vienna, Austria
| | - Tamas Ordog
- Epigenomics Program, Center for Individualized Medicine, Mayo Clinic, Rochester, MN, USA
- Department of Physiology and Biomedical Engineering and Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, MN, USA
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11
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Katebifar S, Jaiswal D, Arul MR, Novak S, Nip J, Kalajzic I, Rudraiah S, Kumbar SG. Natural Polymer-Based Micronanostructured Scaffolds for Bone Tissue Engineering. Methods Mol Biol 2022; 2394:669-691. [PMID: 35094352 DOI: 10.1007/978-1-0716-1811-0_35] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Although bone tissue allografts and autografts aremoften used as a regenerative tissue during the bone healing, their availability, donor site morbidity, and immune response to grafted tissue are limiting factors their more common usage. Tissue engineered implants, such as acellular or cellular polymeric structures, can be an alternative solution. A variety of scaffold fabrication techniques including electrospinning, particulate leaching, particle sintering, and more recently 3D printing have been used to create scaffolds with interconnected pores and mechanical properties for tissue regeneration. Simply combining particle sintering and molecular self-assembly to create porous microstructures with imbued nanofibers to produce micronanostructures for tissue regeneration applications. Natural polymers like polysaccharides, proteins and peptides of plant or animal origin have gained significant attention due to their assured biocompatibility in tissue regeneration. However, majority of these polymers are water soluble and structures derived from them are in the form of hydrogels and require additional stabilization via cross-linking. For bone healing applications scaffolds are required to be strong, and support attachment, proliferation and differentiation of osteoprogenitors into osteoblasts. Our ongoing work utilizes plant polysaccharide cellulose derivatives and collagen to create mechanically stable and bioactive micronanostructured scaffold for bone tissue engineering. Scaffold microstructure is essentially solvent sintered cellulose acetate (CA) microspheres in the form of a negative template for trabecular bone with defined pore and mechanical properties. Collagen nanostructures are imbued into the 3D environment of CA scaffolds using collagen molecular self-assembly principles. The resultant CA-collagen micronanostructures provide the benefits of combined polymers and serve as an alternative material platform to many FDA approved polyesters. Our ongoing studies and published work confirm improved osteoprogenitor adhesion, proliferation, migration, differentiation, extracellular matrix (ECM) secretion in promoting bone healing. In this chapter we will provide a detailed protocol on the creation of micronanostructured CA-collagen scaffolds and their characterization for bone tissue engineering using human mesenchymal stem cells.
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Affiliation(s)
- Sara Katebifar
- Department of Biomedical Engineering, University of Connecticut, Storrs, CT, USA
- Department of Orthopedic Surgery, University of Connecticut Health, Farmington, CT, USA
| | - Devina Jaiswal
- Department of Biomedical Engineering, Western New England University, Springfield, MA, USA
| | - Michael R Arul
- Department of Orthopedic Surgery, University of Connecticut Health, Farmington, CT, USA
| | - Sanja Novak
- Department of Reconstructive Sciences, University of Connecticut Health, Farmington, CT, USA
| | - Jonathan Nip
- Department of Biomedical Engineering, University of Connecticut, Storrs, CT, USA
- Department of Orthopedic Surgery, University of Connecticut Health, Farmington, CT, USA
| | - Ivo Kalajzic
- Department of Reconstructive Sciences, University of Connecticut Health, Farmington, CT, USA
| | - Swetha Rudraiah
- Department of Orthopedic Surgery, University of Connecticut Health, Farmington, CT, USA
- Department of Pharmaceutical Sciences, University of Saint Joseph, Hartford, CT, USA
| | - Sangamesh G Kumbar
- Department of Biomedical Engineering, University of Connecticut, Storrs, CT, USA.
- Department of Orthopedic Surgery, University of Connecticut Health, Farmington, CT, USA.
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12
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Vesprey A, Suh ES, Aytürk DG, Yang X, Rogers M, Sosa B, Niu Y, Kalajzic I, Ivashkiv LB, Bostrom MPG, Ayturk UM. Tmem100- and Acta2-Lineage Cells Contribute to Implant Osseointegration in a Mouse Model. J Bone Miner Res 2021; 36:1000-1011. [PMID: 33528844 PMCID: PMC8715516 DOI: 10.1002/jbmr.4264] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 01/18/2021] [Accepted: 01/26/2021] [Indexed: 11/11/2022]
Abstract
Metal implants are commonly used in orthopedic surgery. The mechanical stability and longevity of implants depend on adequate bone deposition along the implant surface. The cellular and molecular mechanisms underlying peri-implant bone formation (ie, osseointegration) are incompletely understood. Herein, our goal was to determine the specific bone marrow stromal cell populations that contribute to bone formation around metal implants. To do this, we utilized a mouse tibial implant model that is clinically representative of human joint replacement procedures. Using a lineage-tracing approach, we found that both Acta2.creERT2 and Tmem100.creERT2 lineage cells are involved in peri-implant bone formation, and Pdgfra- and Ly6a/Sca1-expressing stromal cells (PαS cells) are highly enriched in both lineages. Single-cell RNA-seq analysis indicated that PαS cells are quiescent in uninjured bone tissue; however, they express markers of proliferation and osteogenic differentiation shortly after implantation surgery. Our findings indicate that PαS cells are mobilized to repair bone tissue and participate in implant osseointegration after surgery. Biologic therapies targeting PαS cells might improve osseointegration in patients undergoing orthopedic procedures. © 2021 American Society for Bone and Mineral Research (ASBMR).
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Affiliation(s)
| | | | | | - Xu Yang
- Hospital for Special Surgery, New York, NY, USA
| | | | | | - Yingzhen Niu
- Hospital for Special Surgery, New York, NY, USA
- Department of Joint Surgery, Hebei Medical University Third Affiliated Hospital, Shijiazhuang, China
| | - Ivo Kalajzic
- Department of Genetics and Genome Sciences, University of Connecticut, Farmington, CT, USA
| | - Lionel B Ivashkiv
- Hospital for Special Surgery, New York, NY, USA
- Departments of Medicine and Immunology, Weill Cornell Medical College, New York, NY, USA
| | - Mathias PG Bostrom
- Hospital for Special Surgery, New York, NY, USA
- Department of Orthopaedic Surgery, Weill Cornell Medical College, New York, NY, USA
| | - Ugur M Ayturk
- Hospital for Special Surgery, New York, NY, USA
- Department of Orthopaedic Surgery, Weill Cornell Medical College, New York, NY, USA
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13
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Matthews BG, Novak S, Sbrana FV, Funnell JL, Cao Y, Buckels EJ, Grcevic D, Kalajzic I. Heterogeneity of murine periosteum progenitors involved in fracture healing. eLife 2021; 10:e58534. [PMID: 33560227 PMCID: PMC7906599 DOI: 10.7554/elife.58534] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 02/08/2021] [Indexed: 12/15/2022] Open
Abstract
The periosteum is the major source of cells involved in fracture healing. We sought to characterize progenitor cells and their contribution to bone fracture healing. The periosteum is highly enriched with progenitor cells, including Sca1+ cells, fibroblast colony-forming units, and label-retaining cells compared to the endosteum and bone marrow. Using lineage tracing, we demonstrate that alpha smooth muscle actin (αSMA) identifies long-term, slow-cycling, self-renewing osteochondroprogenitors in the adult periosteum that are functionally important for bone formation during fracture healing. In addition, Col2.3CreER-labeled osteoblast cells contribute around 10% of osteoblasts but no chondrocytes in fracture calluses. Most periosteal osteochondroprogenitors following fracture can be targeted by αSMACreER. Previously identified skeletal stem cell populations were common in periosteum but contained high proportions of mature osteoblasts. We have demonstrated that the periosteum is highly enriched with skeletal progenitor cells, and there is heterogeneity in the populations of cells that contribute to mature lineages during periosteal fracture healing.
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Affiliation(s)
- Brya G Matthews
- Department of Molecular Medicine and Pathology, University of AucklandAucklandNew Zealand
- Department of Reconstructive Sciences, UConn HealthFarmingtonUnited States
| | - Sanja Novak
- Department of Reconstructive Sciences, UConn HealthFarmingtonUnited States
| | - Francesca V Sbrana
- Department of Reconstructive Sciences, UConn HealthFarmingtonUnited States
| | - Jessica L Funnell
- Department of Reconstructive Sciences, UConn HealthFarmingtonUnited States
| | - Ye Cao
- Department of Molecular Medicine and Pathology, University of AucklandAucklandNew Zealand
| | - Emma J Buckels
- Department of Molecular Medicine and Pathology, University of AucklandAucklandNew Zealand
| | - Danka Grcevic
- Department of Physiology and Immunology, University of ZagrebZagrebCroatia
- Croatian Intitute for Brain Research, University of ZagrebZagrebCroatia
| | - Ivo Kalajzic
- Department of Reconstructive Sciences, UConn HealthFarmingtonUnited States
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14
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Abstract
Diabetics are at increased risk for fracture, and experience severely impaired skeletal healing characterized by delayed union or nonunion of the bone. The periosteum harbors osteochondral progenitors that can differentiate into chondrocytes and osteoblasts, and this connective tissue layer is required for efficient fracture healing. While bone marrow-derived stromal cells have been studied extensively in the context of diabetic skeletal repair and osteogenesis, the effect of diabetes on the periosteum and its ability to contribute to bone regeneration has not yet been explicitly evaluated. Within this study, we utilized an established murine model of type I diabetes to evaluate periosteal cell differentiation capacity, proliferation, and availability under the effect of a diabetic environment. Periosteal cells from diabetic mice were deficient in osteogenic differentiation ability in vitro, and diabetic mice had reduced periosteal populations of mesenchymal progenitors with a corresponding reduction in proliferation capacity following injury. Additionally, fracture callus mineralization and mature osteoblast activity during periosteum-mediated healing was impaired in diabetic mice compared to controls. We propose that the effect of diabetes on periosteal progenitors and their ability to aid in skeletal repair directly impairs fracture healing.
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Affiliation(s)
- Laura Doherty
- Department of Orthopaedic Surgery, UConn Musculoskeletal Institute, UConn Health, Farmington, CT, USA
| | - Matthew Wan
- Department of Orthopaedic Surgery, UConn Musculoskeletal Institute, UConn Health, Farmington, CT, USA
| | - Ivo Kalajzic
- Department of Reconstructive Sciences, UConn School of Dental Medicine, Farmington, CT, USA
| | - Archana Sanjay
- Department of Orthopaedic Surgery, UConn Musculoskeletal Institute, UConn Health, Farmington, CT, USA.
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15
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Novak S, Roeder E, Sinder BP, Adams DJ, Siebel CW, Grcevic D, Hankenson KD, Matthews BG, Kalajzic I. Modulation of Notch1 signaling regulates bone fracture healing. J Orthop Res 2020; 38:2350-2361. [PMID: 32141629 PMCID: PMC7483882 DOI: 10.1002/jor.24650] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Revised: 01/30/2020] [Accepted: 02/22/2020] [Indexed: 02/04/2023]
Abstract
Fracture healing involves interactions of different cell types, driven by various growth factors, and signaling cascades. Periosteal mesenchymal progenitor cells give rise to the majority of osteoblasts and chondrocytes in a fracture callus. Notch signaling has emerged as an important regulator of skeletal cell proliferation and differentiation. We investigated the effects of Notch signaling during the fracture healing process. Increased Notch signaling in osteochondroprogenitor cells driven by overexpression of Notch1 intracellular domain (NICD1) (αSMACreERT2 mice crossed with Rosa-NICD1) during fracture resulted in less cartilage, more mineralized callus tissue, and stronger and stiffer bones after 3 weeks. Periosteal cells overexpressing NICD1 showed increased proliferation and migration in vitro. In vivo data confirmed that increased Notch1 signaling caused expansion of alpha-smooth muscle actin (αSMA)-positive cells and their progeny including αSMA-derived osteoblasts in the callus without affecting osteoclast numbers. In contrast, anti-NRR1 antibody treatment to inhibit Notch1 signaling resulted in increased callus cartilage area, reduced callus bone mass, and reduced biomechanical strength. Our study shows a positive effect of induced Notch1 signaling on the fracture healing process, suggesting that stimulating the Notch pathway could be beneficial for fracture repair.
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Affiliation(s)
- Sanja Novak
- Department of Reconstructive Sciences, UConn Health, Farmington, CT, USA
| | - Emilie Roeder
- Department of Reconstructive Sciences, UConn Health, Farmington, CT, USA
| | - Benjamin P. Sinder
- Department of Reconstructive Sciences, UConn Health, Farmington, CT, USA
| | - Douglas J. Adams
- Department of Orthopedic Surgery, UConn Health, Farmington, CT, USA;,Department of Orthopedics, University of Colorado, Aurora, CO, USA
| | | | - Danka Grcevic
- Department of Physiology and Immunology, School of Medicine, University of Zagreb, Zagreb 10000, Croatia
| | - Kurt D. Hankenson
- Department of Orthopaedic Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Brya G. Matthews
- Department of Reconstructive Sciences, UConn Health, Farmington, CT, USA;,Department of Molecular Medicine and Pathology, University of Auckland, Auckland 1023, New Zealand
| | - Ivo Kalajzic
- Department of Reconstructive Sciences, UConn Health, Farmington, CT, USA
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16
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Thaler R, Khani F, Denbeigh JM, Sturmlechner I, Zhou X, Pichurin O, Dudakovic A, Zhong J, Lee JH, Natarajan R, Kalajzic I, Deyle DR, Paschalis EP, Misof B, Ordog T, van Wijnen AJ. Vitamin C epigenetically controls osteogenesis and bone mineralization. Bone Rep 2020. [DOI: 10.1016/j.bonr.2020.100346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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17
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Basova L, Parfitt GJ, Richardson A, Delcroix V, Umazume T, Pelaez D, Tse DT, Kalajzic I, Di Girolamo N, Jester JV, Makarenkova HP. Origin and Lineage Plasticity of Endogenous Lacrimal Gland Epithelial Stem/Progenitor Cells. iScience 2020; 23:101230. [PMID: 32559730 PMCID: PMC7303985 DOI: 10.1016/j.isci.2020.101230] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 04/03/2020] [Accepted: 05/29/2020] [Indexed: 02/06/2023] Open
Abstract
The lacrimal gland (LG) is an exocrine organ responsible for the secretion of aqueous tear film. Regenerative and stem cell therapies that target LG repair are coming to the fore, although our understanding of LG cell lineage hierarchy is still incomplete. We utilize the analysis of label-retaining cells (LRCs) and genetic lineage tracing to define LG cell lineage hierarchy. Our study suggests that embryonic LG contains unique long-lived multipotent stem cells that give rise to all postnatal epithelial cell types. Following birth, lineages become established and the fate of progenitor cell descendants becomes restricted. However, some cell lineages retain plasticity after maturation and can trans-differentiate into other cell types upon injury. The demonstration that the LG contains progenitor cells with different levels of plasticity has profound implications for our understanding of LG gland function in homeostasis and disease and will be helpful for developing stem cell-based therapies in the future. Multipotent stem cells differentiate into distal Sox10+ and proximal Sox10− lineages Lineage-restricted progenitor cells sustain the long-term lacrimal gland maintenance Label-retaining cells are localized in the intercalated ducts and excretory ducts Some cell lineages in the adult lacrimal gland retain plasticity
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Affiliation(s)
- Liana Basova
- Department of Molecular Medicine, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Geraint J Parfitt
- School of Optometry and Vision Sciences, Cardiff University, Maindy Road, Cardiff CF24 4HQ, UK; European Cancer Stem Cell Research Institute, Cardiff University, Maindy Road, Cardiff CF24 4HQ, UK; The Gavin Herbert Eye Institute, University of California, Irvine, CA 92697, USA
| | - Alex Richardson
- Department of Ophthalmology, School of Medical Sciences, University of New South Wales, Sydney, NSW 2052, Australia
| | - Vanessa Delcroix
- Department of Molecular Medicine, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Takeshi Umazume
- Department of Molecular Medicine, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Daniel Pelaez
- Department of Ophthalmology/Bascom Palmer Eye Institute, Miami, FL, USA
| | - David T Tse
- Department of Ophthalmology/Bascom Palmer Eye Institute, Miami, FL, USA
| | - Ivo Kalajzic
- Reconstructive Sciences Center for Regenerative Medicine and Skeletal Development, University of Connecticut (UCONN) Health, Farmington, CT, USA
| | - Nick Di Girolamo
- Department of Ophthalmology, School of Medical Sciences, University of New South Wales, Sydney, NSW 2052, Australia
| | - James V Jester
- The Gavin Herbert Eye Institute, University of California, Irvine, CA 92697, USA
| | - Helen P Makarenkova
- Department of Molecular Medicine, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
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18
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Youngstrom DW, Zondervan RL, Doucet NR, Acevedo PK, Sexton HE, Gardner EA, Anderson JS, Kushwaha P, Little HC, Rodriguez S, Riddle RC, Kalajzic I, Wong GW, Hankenson KD. CTRP3 Regulates Endochondral Ossification and Bone Remodeling During Fracture Healing. J Orthop Res 2020; 38:996-1006. [PMID: 31808575 PMCID: PMC7162724 DOI: 10.1002/jor.24553] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Accepted: 11/24/2019] [Indexed: 02/04/2023]
Abstract
C1q/TNF-related protein 3 (CTRP3) is a cytokine known to regulate a variety of metabolic processes. Though previously undescribed in the context of bone regeneration, high throughput gene expression experiments in mice identified CTRP3 as one of the most highly upregulated genes in fracture callus tissue. Hypothesizing a positive regulatory role for CTRP3 in bone regeneration, we phenotyped skeletal development and fracture healing in CTRP3 knockout (KO) and CTRP3 overexpressing transgenic (TG) mice relative to wild-type (WT) control animals. CTRP3 KO mice experienced delayed endochondral fracture healing, resulting in abnormal mineral distribution, the presence of periosteal marrow compartments, and a nonunion-like state. Decreased osteoclast number was also observed in CTRP3 KO mice, whereas CTRP3 TG mice underwent accelerated callus remodeling. Gene expression profiling revealed a broad impact on osteoblast/osteoclast lineage commitment and metabolism, including arrested progression toward mature skeletal lineages in the KO group. A single systemic injection of CTRP3 protein at the time of fracture was insufficient to phenocopy the chronic TG healing response in WT mice. By associating CTRP3 levels with fracture healing progression, these data identify a novel protein family with potential therapeutic and diagnostic value. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:00-19966, 2020.
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Affiliation(s)
- Daniel W. Youngstrom
- Department of Orthopaedic Surgery, University of Michigan Medical School, Ann Arbor, Michigan, USA;,Department of Orthopaedic Surgery, University of Connecticut Health Center, Farmington, Connecticut, USA;,Correspondence should be addressed to Dr. Daniel W. Youngstrom:
| | - Robert L. Zondervan
- Department of Orthopaedic Surgery, University of Michigan Medical School, Ann Arbor, Michigan, USA;,Department of Physiology, Michigan State University College of Osteopathic Medicine, East Lansing, Michigan, USA
| | - Nicole R. Doucet
- Department of Orthopaedic Surgery, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Parker K. Acevedo
- Department of Orthopaedic Surgery, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Hannah E. Sexton
- Department of Orthopaedic Surgery, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Emily A. Gardner
- Department of Orthopaedic Surgery, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - JonCarlos S. Anderson
- Department of Orthopaedic Surgery, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Priyanka Kushwaha
- Department of Orthopaedic Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Hannah C. Little
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Susana Rodriguez
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Ryan C. Riddle
- Department of Orthopaedic Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Ivo Kalajzic
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, Connecticut, USA
| | - G. William Wong
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Kurt D. Hankenson
- Department of Orthopaedic Surgery, University of Michigan Medical School, Ann Arbor, Michigan, USA
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19
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Basile M, Marchegiani F, Novak S, Kalajzic I, Di Pietro R. Human amniotic fluid stem cells attract osteoprogenitor cells in bone healing. J Cell Physiol 2020; 235:4643-4654. [PMID: 31650536 PMCID: PMC7018542 DOI: 10.1002/jcp.29342] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 09/30/2019] [Indexed: 02/05/2023]
Abstract
Current treatments of large bone defects are based on autologous or allogenic bone transplantation. Human amniotic fluid stem cells (hAFSCs) were evaluated for their potential in bone regenerative medicine. In this study, hAFSCs were transduced with lentiviral vector harboring red fluorescent protein to investigate their role in the regeneration of critical-size bone defects in calvarial mouse model. To distinguish donor versus recipient cells, a transgenic mouse model carrying GFP fluorescent reporter was used as recipient to follow the fate of hAFSCs transplanted in vivo into Healos® scaffold. Our results showed that transduced hAFSCs can be tracked in vivo directly at the site of transplantation. The presence of GFP positive cells in the scaffold at 3 and 6 weeks after transplantation indicates that donor hAFSCs can recruit host cells during the repair process. These observations help clarify the role of hAFSCs in bone tissue repair.
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Affiliation(s)
- Mariangela Basile
- Department of Reconstructive Sciences, UConn Health, Farmington, Connecticut
- Department of Medicine and Ageing Sciences, G. d’Annunzio University of Chieti-Pescara, Italy
- StemTeCh Group, CAST, G. d’Annunzio University of Chieti-Pescara, Italy
| | - Francesco Marchegiani
- Department of Surgical, Oncological and Gastroenterological Sciences, University of Padua, Padua, Italy
| | - Sanja Novak
- Department of Reconstructive Sciences, UConn Health, Farmington, Connecticut
| | - Ivo Kalajzic
- Department of Reconstructive Sciences, UConn Health, Farmington, Connecticut
| | - Roberta Di Pietro
- Department of Medicine and Ageing Sciences, G. d’Annunzio University of Chieti-Pescara, Italy
- StemTeCh Group, CAST, G. d’Annunzio University of Chieti-Pescara, Italy
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20
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Root SH, Wee NKY, Novak S, Rosen CJ, Baron R, Matthews BG, Kalajzic I. Perivascular osteoprogenitors are associated with transcortical channels of long bones. Stem Cells 2020; 38:769-781. [PMID: 32053258 DOI: 10.1002/stem.3159] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Accepted: 01/23/2020] [Indexed: 12/14/2022]
Abstract
Bone remodeling and regeneration are dependent on resident stem/progenitor cells with the ability to replenish mature osteoblasts and repair the skeleton. Using lineage tracing approaches, we identified a population of Dmp1+ cells that reside within cortical bone and are distinct from osteocytes. Our aims were to characterize this stromal population of transcortical perivascular cells (TPCs) in their resident niche and evaluate their osteogenic potential. To distinguish this population from osteoblasts/osteocytes, we crossed mice containing inducible DMP1CreERT2/Ai9 Tomato reporter (iDMP/T) with Col2.3GFP reporter (ColGFP), a marker of osteoblasts and osteocytes. We observed iDMP/T+;ColGFP- TPCs within cortical bone following tamoxifen injection. These cells were perivascular and located within transcortical channels. Ex vivo bone outgrowth cultures showed TPCs migrated out of the channels onto the plate and expressed stem cell markers such as Sca1, platelet derived growth factor receptor beta (PDGFRβ), and leptin receptor. In a cortical bone transplantation model, TPCs migrate from their vascular niche within cortical bone and contribute to new osteoblast formation and bone tube closure. Treatment with intermittent parathyroid hormone increased TPC number and differentiation. TPCs were unable to differentiate into adipocytes in the presence of rosiglitazone in vitro or in vivo. Altogether, we have identified and characterized a novel stromal lineage-restricted osteoprogenitor that is associated with transcortical vessels of long bones. Functionally, we have demonstrated that this population can migrate out of cortical bone channels, expand, and differentiate into osteoblasts, therefore serving as a source of progenitors contributing to new bone formation.
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Affiliation(s)
- Sierra H Root
- Department of Reconstructive Sciences, UConn Health, Farmington, Connecticut, USA
| | - Natalie K Y Wee
- Department of Reconstructive Sciences, UConn Health, Farmington, Connecticut, USA
| | - Sanja Novak
- Department of Reconstructive Sciences, UConn Health, Farmington, Connecticut, USA
| | - Clifford J Rosen
- Department of Medicine, Tufts University School of Medicine, Maine Medical Center Research Institute, Scarborough, Maine, USA
| | - Roland Baron
- Department of Oral Medicine, Infection and Immunity, Division of Bone and Mineral Research, Harvard School of Dental Medicine, Boston, Massachusetts, USA.,Department of Medicine, Harvard Medical School, Boston, Massachusetts, USA
| | - Brya G Matthews
- Department of Reconstructive Sciences, UConn Health, Farmington, Connecticut, USA.,Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand
| | - Ivo Kalajzic
- Department of Reconstructive Sciences, UConn Health, Farmington, Connecticut, USA
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21
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Matthews BG, Wee NKY, Widjaja VN, Price JS, Kalajzic I, Windahl SH. αSMA Osteoprogenitor Cells Contribute to the Increase in Osteoblast Numbers in Response to Mechanical Loading. Calcif Tissue Int 2020; 106:208-217. [PMID: 31673746 PMCID: PMC6995756 DOI: 10.1007/s00223-019-00624-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2019] [Accepted: 10/11/2019] [Indexed: 01/11/2023]
Abstract
Bone is a dynamic tissue that site-specifically adapts to the load that it experiences. In response to increasing load, the cortical bone area is increased, mainly through enhanced periosteal bone formation. This increase in area is associated with an increase in the number of bone-forming osteoblasts; however, the origin of the cells involved remains unclear. Alpha-smooth muscle actin (αSMA) is a marker of early osteoprogenitor cells in the periosteum, and we hypothesized that the new osteoblasts that are activated by loading could originate from αSMA-expressing cells. Therefore, we used an in vivo fate-mapping approach in an established axial loading model to investigate the role of αSMA-expressing cells in the load-induced increase in osteoblasts. Histomorphometric analysis was applied to measure the number of cells of different origin on the periosteal surface in the most load-responsive region of the mouse tibia. A single loading session failed to increase the number of periosteal αSMA-expressing cells and osteoblasts. However, in response to multiple episodes of loading, the caudal, but not the cranial, periosteal surface was lined with an increased number of osteoblasts originating from αSMA-expressing cells 5 days after the initial loading session. The proportion of osteoblasts derived from αSMA-labeled progenitors increased by 70% (p < 0.05), and the proportion of αSMA-labeled cells that had differentiated into osteoblasts was doubled. We conclude that αSMA-expressing osteoprogenitors can differentiate and contribute to the increase in periosteal osteoblasts induced by mechanical loading in a site-specific manner.
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Affiliation(s)
- B G Matthews
- Department of Reconstructive Sciences, UConn Health, Farmington, CT, USA
- Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand
| | - N K Y Wee
- Department of Reconstructive Sciences, UConn Health, Farmington, CT, USA
| | - V N Widjaja
- Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand
| | - J S Price
- School of Veterinary Sciences, University of Bristol, Bristol, UK
- Royal Agricultural University, Cirencester, UK
| | - I Kalajzic
- Department of Reconstructive Sciences, UConn Health, Farmington, CT, USA
| | - S H Windahl
- School of Veterinary Sciences, University of Bristol, Bristol, UK.
- Division of Pathology, Department of Laboratory Medicine, Karolinska Institutet, Huddinge, Sweden.
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22
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Novak S, Roeder E, Kalinowski J, Jastrzebski S, Aguila HL, Lee SK, Kalajzic I, Lorenzo JA. Osteoclasts Derive Predominantly from Bone Marrow-Resident CX 3CR1 + Precursor Cells in Homeostasis, whereas Circulating CX 3CR1 + Cells Contribute to Osteoclast Development during Fracture Repair. J Immunol 2020; 204:868-878. [PMID: 31915261 DOI: 10.4049/jimmunol.1900665] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Accepted: 12/12/2019] [Indexed: 01/10/2023]
Abstract
Osteoclasts (OC) originate from either bone marrow (BM)-resident or circulating myeloid OC progenitors (OCP) expressing the receptor CX3CR1. Multiple lines of evidence argue that OCP in homeostasis and inflammation differ. We investigated the relative contributions of BM-resident and circulating OCP to osteoclastogenesis during homeostasis and fracture repair. Using CX3CR1-EGFP/TRAP tdTomato mice, we found CX3CR1 expression in mononuclear cells, but not in multinucleated TRAP+ OC. However, CX3CR1-expressing cells generated TRAP+ OC on bone within 5 d in CX3CR1CreERT2/Ai14 tdTomato reporter mice. To define the role that circulating cells play in osteoclastogenesis during homeostasis, we parabiosed TRAP tdTomato mice (CD45.2) on a C57BL/6 background with wild-type (WT) mice (CD45.1). Flow cytometry (CD45.1/45.2) demonstrated abundant blood cell mixing between parabionts after 2 wk. At 4 wk, there were numerous tdTomato+ OC in the femurs of TRAP tdTomato mice but almost none in WT mice. Similarly, cultured BM stimulated to form OC demonstrated multiple fluorescent OC in cell cultures from TRAP tdTomato mice, but not from WT mice. Finally, flow cytometry confirmed low-level engraftment of BM cells between parabionts but significant engraftment in the spleens. In contrast, during fracture repair, we found that circulating CX3CR1+ cells migrated to bone, lost expression of CX3CR1, and became OC. These data demonstrate that OCP, but not mature OC, express CX3CR1 during both homeostasis and fracture repair. We conclude that, in homeostasis mature OC derive predominantly from BM-resident OCP, whereas during fracture repair, circulating CX3CR1+ cells can become OC.
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Affiliation(s)
- Sanja Novak
- Department of Reconstructive Sciences, UConn Health, Farmington, CT 06030
| | - Emilie Roeder
- Department of Reconstructive Sciences, UConn Health, Farmington, CT 06030
| | | | | | - Hector L Aguila
- Department of Immunology, UConn Health, Farmington, CT 06030
| | - Sun-Kyeong Lee
- University of Connecticut Center on Aging, UConn Health, Farmington, CT 06030; and
| | - Ivo Kalajzic
- Department of Reconstructive Sciences, UConn Health, Farmington, CT 06030
| | - Joseph A Lorenzo
- Department of Medicine, UConn Health, Farmington, CT 06030; .,Department of Orthopaedic Surgery, UConn Health, Farmington, CT 06030
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23
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Wee NK, Madunic IV, Ivanisevic T, Sinder BP, Kalajzic I. Divergent effects of peripheral and global neuropeptide Y deletion. J Musculoskelet Neuronal Interact 2020; 20:579-590. [PMID: 33265087 PMCID: PMC7716695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
OBJECTIVES Neuropeptide Y (NPY) is involved in the coordination of bone mass and adiposity. However, multiple NPY sources exist and their individual contribution to the skeleton and adiposity not known. The objectives of our study were to evaluate the effects of peripheral mesenchymal derived NPY to the skeleton and adiposity and to compare them to the global NPYKO model. METHODS To study the role of mesenchymal-derived NPY, we crossed conditional NPY (NPYfl/fl) mice with Prx1cre to generate PrxNPYKO mice. The bone phenotype was assessed using micro-CT. The skeletal phenotype of PrxNPYKO mice was subsequently compared to global NPYKO model. We evaluated body weight, adiposity and functionally assessed the feeding response of NPY neurons to determine whether central NPY signaling was altered by Prx1cre. RESULTS We identified the increase in cortical parameters in PrxNPYKO mice with no changes to cancellous bone. This was the opposite phenotype to global NPYKO mice generated from the same conditional allele. Male NPYKOmice have increased adiposity, while PrxNPYKO mice showed no difference, demonstrating that local mesenchymal-derived NPY does not influence adiposity. CONCLUSION NPY mediates both positive and negative effects on bone mass via separate regulatory pathways. Deletion of mesenchymal-derived NPY had a positive effect on bone mass.
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Affiliation(s)
- Natalie K.Y. Wee
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, USA
| | - Ivana Vrhovac Madunic
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, USA,Molecular Toxicology Unit, Institute for Medical Research and Occupational Health, Zagreb, Croatia
| | - Tonci Ivanisevic
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, USA,Department of Biochemistry, University of Oxford, Oxford, UK
| | - Benjamin P Sinder
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, USA
| | - Ivo Kalajzic
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, USA,Corresponding author: Ivo Kalajzic, Department of Reconstructive Sciences, MC 3705, School of Dental Medicine, UConn Health, 263 Farmington Ave, Farmington, CT 06030, USA E-mail:
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24
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Sinder BP, Novak S, Wee NKY, Basile M, Maye P, Matthews BG, Kalajzic I. Engraftment of skeletal progenitor cells by bone-directed transplantation improves osteogenesis imperfecta murine bone phenotype. Stem Cells 2019; 38:530-541. [PMID: 31859429 DOI: 10.1002/stem.3133] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 11/22/2019] [Indexed: 12/12/2022]
Abstract
Osteogenesis imperfecta (OI) is a genetic disorder most commonly caused by mutations associated with type I collagen, resulting in a defective collagen bone matrix. Current treatments for OI focus on pharmaceutical strategies to increase the amount of defective bone matrix, but do not address the underlying collagen defect. Introducing healthy donor stem cells that differentiate into osteoblasts producing normal collagen in OI patients has the potential to increase bone mass and correct the mutant collagen matrix. In this study, donor bone marrow stromal cells (BMSCs, also known as bone marrow mesenchymal stem cells) expressing both αSMACreERT2/Ai9 progenitor reporter and osteoblast reporter Col2.3GFP were locally transplanted into the femur of OI murine (OIM) mice. One month post-transplantation, 18% of the endosteal surface was lined by donor Col2.3GFP expressing osteoblasts indicating robust engraftment. Long-term engraftment in the marrow was observed 3 and 6 months post-transplantation. The presence of Col1a2-expressing donor cell-derived cortical bone matrix was detected in transplanted OIM femurs. Local transplantation of BMSCs increased cortical thickness (+12%), the polar moment of inertia (+14%), bone strength (+30%), and stiffness (+30%) 3 months post-transplantation. Engrafted cells expressed progenitor markers CD51 and Sca-1 up to 3 months post-transplantation. Most importantly, 3 months post-transplantation donor cells maintained the ability to differentiate into Col2.3GFP+ osteoblasts in vitro, and in vivo following secondary transplantation into OIM animals. Locally transplanted BMSCs can improve cortical structure and strength, and persist as continued source of osteoblast progenitors in the OIM mouse for at least 6 months.
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Affiliation(s)
- Benjamin P Sinder
- Department of Reconstructive Sciences, UConn Health, Farmington, Connecticut
| | - Sanja Novak
- Department of Reconstructive Sciences, UConn Health, Farmington, Connecticut
| | - Natalie K Y Wee
- Department of Reconstructive Sciences, UConn Health, Farmington, Connecticut
| | - Mariangela Basile
- Department of Reconstructive Sciences, UConn Health, Farmington, Connecticut
| | - Peter Maye
- Department of Reconstructive Sciences, UConn Health, Farmington, Connecticut
| | - Brya G Matthews
- Department of Reconstructive Sciences, UConn Health, Farmington, Connecticut.,Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand
| | - Ivo Kalajzic
- Department of Reconstructive Sciences, UConn Health, Farmington, Connecticut
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25
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Doherty L, Yu J, Wang X, Hankenson KD, Kalajzic I, Sanjay A. A PDGFRβ-PI3K signaling axis mediates periosteal cell activation during fracture healing. PLoS One 2019; 14:e0223846. [PMID: 31665177 PMCID: PMC6821073 DOI: 10.1371/journal.pone.0223846] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Accepted: 09/30/2019] [Indexed: 12/21/2022] Open
Abstract
Insufficient and delayed fracture healing remain significant public health problems with limited therapeutic options. Phosphoinositide 3-kinase (PI3K) signaling, a major pathway involved in regulation of fracture healing, promotes proliferation, migration, and differentiation of osteoprogenitors. We have recently reported that knock-in mice with a global increase in PI3K signaling (gCblYF) show enhanced femoral fracture healing characterized by an extraordinary periosteal response to injury. Interestingly, of all growth factor receptors involved in fracture healing, PI3K directly binds only to PDGFR. Given these findings, we hypothesized a PDGFR-PI3K interaction is necessary for mediating robust periosteal cell activation following fracture. In this study, we isolated primary periosteal cells from gCblYF mice to analyze cross-talk between the PDGFRβ and PI3K signaling pathways. We found PDGFRβ signaling contributes to robust Akt phosphorylation in periosteal cells in comparison with other growth factor signaling pathways. Additionally, we performed femoral fractures on gCblYF mice with a conditional removal of PDGFRβ in mesenchymal progenitors using inducible alpha smooth muscle actin (αSMA) CreERT2 mice. Our studies showed that depletion of PDGFRβ signaling within these progenitors in the early phase of fracture healing significantly abrogates PI3K-mediated periosteal activation and proliferation three days after fracture. Combined, these results suggest that PDGFRβ signaling through PI3K is necessary for robust periosteal activation in the earliest phases of fracture healing.
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Affiliation(s)
- Laura Doherty
- Department of Orthopaedic Surgery, UConn Health, Farmington, Connecticut, United States of America
| | - Jungeun Yu
- Department of Orthopaedic Surgery, UConn Health, Farmington, Connecticut, United States of America
| | - Xi Wang
- Department of Reconstructive Sciences, UConn Health, Farmington, Connecticut, United States of America
| | - Kurt D. Hankenson
- Department of Orthopaedic Surgery, School of Medicine, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Ivo Kalajzic
- Department of Reconstructive Sciences, UConn Health, Farmington, Connecticut, United States of America
| | - Archana Sanjay
- Department of Orthopaedic Surgery, UConn Health, Farmington, Connecticut, United States of America
- * E-mail:
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26
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Kalajzic I. A New Osteocytic Cell Line, Raising New Questions and Opportunities. J Bone Miner Res 2019; 34:977-978. [PMID: 31173397 PMCID: PMC6860015 DOI: 10.1002/jbmr.3736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 03/26/2019] [Accepted: 03/29/2019] [Indexed: 11/10/2022]
Affiliation(s)
- Ivo Kalajzic
- Reconstructive Sciences, School of Dental Medicine, UConn Health, Farmington, CT, USA
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27
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Manoukian OS, Arul MR, Rudraiah S, Kalajzic I, Kumbar SG. Aligned microchannel polymer-nanotube composites for peripheral nerve regeneration: Small molecule drug delivery. J Control Release 2019; 296:54-67. [PMID: 30658124 PMCID: PMC6379151 DOI: 10.1016/j.jconrel.2019.01.013] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 01/03/2019] [Accepted: 01/14/2019] [Indexed: 12/18/2022]
Abstract
Peripheral nerve injury accounts for roughly 2.8% of all trauma patients with an annual cost of 7 billion USD in the U.S. alone. Current treatment options rely on surgical intervention with the use of an autograft, despite associated shortcomings. Engineered nerve guidance conduits, stem cell therapies, and transient electrical stimulation have reported to increase speeds of functional recovery. As an alternative to the conduction effects of electrical stimulation, we have designed and optimized a nerve guidance conduit with aligned microchannels for the sustained release of a small molecule drug that promotes nerve impulse conduction. A biodegradable chitosan structure reinforced with drug-loaded halloysite nanotubes (HNT) was formed into a foam-like conduit with interconnected, longitudinally-aligned pores with an average pore size of 59.3 ± 14.2 μm. The aligned composite with HNTs produced anisotropic mechanical behavior with a Young's modulus of 0.33 ± 0.1 MPa, very similar to that of native peripheral nerve. This manuscript reports on the sustained delivery of 4-Aminopyridine (4AP, molecular weight 94.1146 g/mol), a potassium-channel blocker as a growth factor alternative to enhance the rate of nerve regeneration. The conduit formulation released a total of 30 ± 2% of the encapsulated 4AP in the first 7 days. Human Schwann cells showed elevated expression of key proteins such as nerve growth factor, myelin protein zero, and brain derived neurotrophic factor in a 4AP dose dependent manner. Preliminary in vivo studies in a critical-sized sciatic nerve defect in Wistar rats confirmed conduit suturability and strength to withstand ambulatory forces over 4 weeks of their implantation. Histological evaluations suggest conduit biocompatibility and Schwann cell infiltration and organization within the conduit and lumen. These nerve guidance conduits and 4AP sustained delivery may serve as an attractive strategy for nerve repair and regeneration.
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Affiliation(s)
- Ohan S Manoukian
- Department of Biomedical Engineering, University of Connecticut, Storrs, CT, USA; Department of Orthopaedic Surgery, University of Connecticut Health, Farmington, CT, USA
| | - Michael R Arul
- Department of Orthopaedic Surgery, University of Connecticut Health, Farmington, CT, USA
| | - Swetha Rudraiah
- Department of Orthopaedic Surgery, University of Connecticut Health, Farmington, CT, USA; Department of Pharmaceutical Sciences, University of Saint Joseph, Hartford, CT, USA
| | - Ivo Kalajzic
- Department of Reconstructive Sciences, University of Connecticut Health, Farmington, CT, USA
| | - Sangamesh G Kumbar
- Department of Biomedical Engineering, University of Connecticut, Storrs, CT, USA; Department of Orthopaedic Surgery, University of Connecticut Health, Farmington, CT, USA.
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28
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Wee NKY, Sinder BP, Novak S, Wang X, Stoddard C, Matthews BG, Kalajzic I. Skeletal phenotype of the neuropeptide Y knockout mouse. Neuropeptides 2019; 73:78-88. [PMID: 30522780 PMCID: PMC6326877 DOI: 10.1016/j.npep.2018.11.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Revised: 11/04/2018] [Accepted: 11/28/2018] [Indexed: 10/27/2022]
Abstract
Neuropeptide Y (NPY) is involved in multiple processes such as behavior, energy and bone metabolism. Previous studies have relied on global NPY depletion to examine its effects on bone. However, this approach is unable to distinguish the central or local source of NPY influencing bone. Our aim was to identify which cells within the skeleton express Npy and establish a model that will enable us to differentiate effects of NPY derived from different cell types. We have generated the NPY floxed (NPYflox) mice using CRISPR technology. By crossing the NPYflox mice with Hypoxanthine Phosphoribosyltransferase 1 (Hprt)-cre to generate a global knockout, we were able to validate and confirm loss of Npy transcript and protein in our global NPYKO. Global deletion of NPY results in a smaller femoral cortical cross-sectional area (-12%) and reduced bone strength (-18%) in male mice. In vitro, NPY-deficient bone marrow stromal cells (BMSCs) showed increase in osteogenic differentiation detected by increases in alkaline phosphatase staining and bone sialoprotein and osteocalcin expression. Despite both sexes presenting with increased adiposity, female mice had no alterations in bone mass, suggesting that NPY may have sex-specific effects on bone. In this study we identified Npy expression in the skeleton and examined the effect of global NPY depletion to bone mass. The differential impact of NPY deletion in cortical and cancellous compartments along with differences in phenotypes between in vitro and in vivo, highlights the complex nature of NPY signaling, indicative of distinct sources that can be dissected in the future using this NPYflox model.
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Affiliation(s)
- Natalie K Y Wee
- Department of Reconstructive Sciences, Farmington, CT 06030, USA
| | | | - Sanja Novak
- Department of Reconstructive Sciences, Farmington, CT 06030, USA
| | - Xi Wang
- Department of Reconstructive Sciences, Farmington, CT 06030, USA
| | - Chris Stoddard
- Genetics and Genome Sciences, UConn Health, Farmington, CT 06030, USA
| | - Brya G Matthews
- Department of Reconstructive Sciences, Farmington, CT 06030, USA; Department of Molecular Medicine and Pathology, University of Auckland, Auckland 1023, New Zealand
| | - Ivo Kalajzic
- Department of Reconstructive Sciences, Farmington, CT 06030, USA.
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29
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Wang X, Matthews BG, Yu J, Novak S, Grcevic D, Sanjay A, Kalajzic I. PDGF Modulates BMP2-Induced Osteogenesis in Periosteal Progenitor Cells. JBMR Plus 2019; 3:e10127. [PMID: 31131345 PMCID: PMC6524680 DOI: 10.1002/jbm4.10127] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Revised: 09/23/2018] [Accepted: 10/03/2018] [Indexed: 12/15/2022] Open
Abstract
BMPs are used in various clinical applications to promote bone formation. The limited success of the BMPs in clinical settings and supraphysiological doses required for their effects prompted us to evaluate the influence of other signaling molecules, specifically platelet‐derived growth factor (PDGF) on BMP2‐induced osteogenesis. Periosteal cells make a major contribution to fracture healing. We detected broad expression of PDGF receptor beta (PDGFRβ) within the intact periosteum and healing callus during fracture repair. In vitro, periosteum‐derived progenitor cells were highly responsive to PDGF as demonstrated by increased proliferation and decreased apoptosis. However, PDGF blocked BMP2‐induced osteogenesis by inhibiting the canonical BMP2/Smad pathway and downstream target gene expression. This effect is mediated via PDGFRβ and involves ERK1/2 MAPK and PI3K/AKT signaling pathways. Therapeutic targeting of the PDGFRβ pathway in periosteum‐mediated bone repair might have profound implications in the treatment of bone disease in the future. © 2018 The Authors JBMR Plus is published by Wiley Periodicals, Inc. on behalf of the American Society for Bone and Mineral Research.
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Affiliation(s)
- Xi Wang
- Department of Reconstructive Sciences UConn Health Farmington CT USA
| | - Brya G Matthews
- Department of Reconstructive Sciences UConn Health Farmington CT USA.,Department of Molecular Medicine and Pathology University of Auckland Auckland New Zealand
| | - Jungeun Yu
- Department of Orthopedic Surgery UConn Health Farmington CT USA
| | - Sanja Novak
- Department of Reconstructive Sciences UConn Health Farmington CT USA
| | - Danka Grcevic
- Department of Physiology and Immunology School of Medicine University of Zagreb Zagreb Croatia
| | - Archana Sanjay
- Department of Orthopedic Surgery UConn Health Farmington CT USA
| | - Ivo Kalajzic
- Department of Reconstructive Sciences UConn Health Farmington CT USA
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30
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Vidovic-Zdrilic I, Vining KH, Vijaykumar A, Kalajzic I, Mooney DJ, Mina M. FGF2 Enhances Odontoblast Differentiation by αSMA + Progenitors In Vivo. J Dent Res 2018; 97:1170-1177. [PMID: 29649366 DOI: 10.1177/0022034518769827] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The goal of this study was to examine the effects of early and limited exposure of perivascular cells expressing α (αSMA) to fibroblast growth factor 2 (FGF2) in vivo. We performed in vivo fate mapping by inducible Cre-loxP and experimental pulp injury in molars to induce reparative dentinogenesis. Our results demonstrate that early delivery of exogenous FGF2 to exposed pulp led to proliferative expansion of αSMA-tdTomato+ cells and their accelerated differentiation into odontoblasts. In vivo lineage-tracing experiments showed that the calcified bridge/reparative dentin in FGF2-treated pulps were lined with an increased number of Dspp+ odontoblasts and devoid of BSP+ osteoblasts. The increased number of odontoblasts derived from αSMA-tdTomato+ cells and the formation of reparative dentin devoid of osteoblasts provide in vivo evidence for the stimulatory effects of FGF signaling on odontoblast differentiation from early progenitors in dental pulp.
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Affiliation(s)
- I Vidovic-Zdrilic
- 1 Departments of Craniofacial Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
| | - K H Vining
- 2 John A. Paulson School of Engineering and Applied Sciences and Wyss Institute for Biologically Inspired Engineering, Harvard University, Cambridge, MA, USA
| | - A Vijaykumar
- 1 Departments of Craniofacial Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
| | - I Kalajzic
- 3 Departments of Reconstructive Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
| | - D J Mooney
- 2 John A. Paulson School of Engineering and Applied Sciences and Wyss Institute for Biologically Inspired Engineering, Harvard University, Cambridge, MA, USA
| | - M Mina
- 1 Departments of Craniofacial Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
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31
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Aravamudhan A, Ramos DM, Nip J, Kalajzic I, Kumbar SG. Micro-Nanostructures of Cellulose-Collagen for Critical Sized Bone Defect Healing. Macromol Biosci 2018; 18:10.1002/mabi.201700263. [PMID: 29178402 PMCID: PMC5835266 DOI: 10.1002/mabi.201700263] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 09/15/2017] [Indexed: 01/12/2023]
Abstract
Bone tissue engineering strategies utilize biodegradable polymeric matrices alone or in combination with cells and factors to provide mechanical support to bone, while promoting cell proliferation, differentiation, and tissue ingrowth. The performance of mechanically competent, micro-nanostructured polymeric matrices, in combination with bone marrow stromal cells (BMSCs), is evaluated in a critical sized bone defect. Cellulose acetate (CA) is used to fabricate a porous microstructured matrix. Type I collagen is then allowed to self-assemble on these microstructures to create a natural polymer-based, micro-nanostructured matrix (CAc). Poly (lactic-co-glycolic acid) matrices with identical microstructures serve as controls. Significantly higher number of implanted host cells are distributed in the natural polymer based micro-nanostructures with greater bone density and more uniform cell distribution. Additionally, a twofold increase in collagen content is observed with natural polymer based scaffolds. This study establishes the benefits of natural polymer derived micro-nanostructures in combination with donor derived BMSCs to repair and regenerate critical sized bone defects. Natural polymer based materials with mechanically competent micro-nanostructures may serve as an alternative material platform for bone regeneration.
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Affiliation(s)
- Aja Aravamudhan
- Skeletal Cranial Biology, UConn Health, Farmington, CT-06030, US
| | - Daisy M. Ramos
- Materials Science and Engineering, University of Connecticut, Storrs, CT-06269, US
| | - Jonathan Nip
- Department of Biomedical Engineering, University of Connecticut, Storrs, CT-06269, US
| | - Ivo Kalajzic
- Department of Reconstructive Sciences, Uconn Health, Farmington, CT-06030, US
| | - Sangamesh G. Kumbar
- Skeletal Cranial Biology, UConn Health, Farmington, CT-06030, US
- Materials Science and Engineering, University of Connecticut, Storrs, CT-06269, US
- Department of Biomedical Engineering, University of Connecticut, Storrs, CT-06269, US
- Department of Orthopaedics, UConn Health, Farmington, CT-06030, US
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32
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Matthews BG, Roeder E, Wang X, Aguila HL, Lee SK, Grcevic D, Kalajzic I. Splenomegaly, myeloid lineage expansion and increased osteoclastogenesis in osteogenesis imperfecta murine. Bone 2017; 103:1-11. [PMID: 28600151 PMCID: PMC5764163 DOI: 10.1016/j.bone.2017.06.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Revised: 05/14/2017] [Accepted: 06/04/2017] [Indexed: 01/14/2023]
Abstract
Osteogenesis imperfecta (OI) is a disease caused by defects in type I collagen production that results in brittle bones. While the pathology is mainly caused by defects in the osteoblast lineage, there is also elevated bone resorption by osteoclasts resulting in high bone turnover in severe forms of the disease. Osteoclasts originate from hematopoietic myeloid cells, however changes in hematopoiesis have not been previously documented in OI. In this study, we evaluated hematopoietic lineage distribution and osteoclast progenitor cell frequency in bone marrow, spleen and peripheral blood of osteogenesis imperfecta murine (OIM) mice, a model of severe OI. We found splenomegaly in all ages examined, and expansion of myeloid lineage cells (CD11b+) in bone marrow and spleen of 7-9week old male OIM animals. OIM spleens also showed an increased frequency of purified osteoclast progenitors. This phenotype is suggestive of chronic inflammation. Isolated osteoclast precursors from both spleen and bone marrow formed osteoclasts more rapidly than wild-type controls. We found that serum TNFα levels were increased in OIM, as was IL1α in OIM females. We targeted inflammation therapeutically by treating growing animals with murine TNFR2:Fc, a compound that blocks TNFα activity. Anti-TNFα treatment marginally decreased spleen mass in OIM females, but failed to reduce bone resorption, or improve bone parameters or fracture rate in OIM animals. We have demonstrated that OIM mice have changes in their hematopoietic system, and form osteoclasts more rapidly even in the absence of OI osteoblast signals, however therapy targeting TNFα did not improve disease parameters.
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Affiliation(s)
- Brya G Matthews
- Department of Reconstructive Sciences, University of Connecticut, Farmington, CT 06030, USA.
| | - Emilie Roeder
- Department of Reconstructive Sciences, University of Connecticut, Farmington, CT 06030, USA
| | - Xi Wang
- Department of Reconstructive Sciences, University of Connecticut, Farmington, CT 06030, USA
| | | | - Sun-Kyeong Lee
- Center on Aging, University of Connecticut, Farmington, CT 06030, USA
| | - Danka Grcevic
- Department of Physiology and Immunology, School of Medicine, University of Zagreb, Zagreb 10000, Croatia
| | - Ivo Kalajzic
- Department of Reconstructive Sciences, University of Connecticut, Farmington, CT 06030, USA.
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Vidovic Zdrilic I, de Azevedo Queiroz IO, Matthews BG, Gomes-Filho JE, Mina M, Kalajzic I. Mineral trioxide aggregate improves healing response of periodontal tissue to injury in mice. J Periodontal Res 2017; 52:1058-1067. [PMID: 28691752 DOI: 10.1111/jre.12478] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/07/2017] [Indexed: 01/02/2023]
Abstract
BACKGROUND AND OBJECTIVE Mineral trioxide aggregate (MTA) is a biomaterial used in endodontic procedures as it exerts beneficial effects on regenerative processes. In this study, we evaluate the effect of MTA on healing of periodontal ligament (PDL) and surrounding tissue, following injury, in a transgenic mouse model and on the differentiation of murine mesenchymal progenitor cells in vitro. MATERIAL AND METHODS We used an inducible Cre-loxP in vivo fate mapping approach to examine the effects of MTA on the contributions of descendants of cells expressing the αSMA-CreERT2 transgene (SMA9+ ) to the PDL and alveolar bone after experimental injury to the root furcation on the maxillary first molars. Col2.3GFP was used as a marker to identify mature osteoblasts, cementoblasts and PDL fibroblasts. The effects of MTA were examined 2, 17 and 30 days after injury and compared histologically with sealing using an adhesive system. The effects of two dilutions of medium conditioned with MTA on proliferation and differentiation of mesenchymal progenitor cells derived from bone marrow (BMSC) and periodontal ligament (PDLC) in vitro were examined using the PrestoBlue viability assay, alkaline phosphatase and Von Kossa staining. The expression of markers of differentiation was assessed using real-time PCR. RESULTS Histological analyses showed better repair in teeth restored with MTA, as shown by greater expansion of SMA9+ progenitor cells and Col2.3GFP+ osteoblasts compared with control teeth. We also observed a positive effect on differentiation of SMA9+ progenitors into osteoblasts and cementoblasts in the apical region distant from the site of injury. The in vitro data showed that MTA-conditioned medium reduced cell viability and osteogenic differentiation in both PDLC and BMSC, indicated by reduced von Kossa staining and lower expression of osteocalcin and bone sialoprotein. In addition, cultures grown in the presence of MTA had marked decreases in SMA9+ and Col2.3GFP+ areas as compared with osteogenic medium, confirming reduced osteogenesis. CONCLUSION MTA promotes regeneration of injured PDL and alveolar bone, reflected as contribution of progenitors (SMA9+ cells) into osteoblasts (Col2.3GFP+ cells). In vitro, MTA-conditioned medium fails to promote osteogenic differentiation of both PDLC and BMSC.
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Affiliation(s)
- I Vidovic Zdrilic
- Department of Pediatric Dentistry, Uconn Health, Farmington, CT, USA
| | | | - B G Matthews
- Department of Reconstructive Sciences, Uconn Health, Farmington, CT, USA
| | - J E Gomes-Filho
- Department of Endodontics, School of Dentistry, São Paulo State University, Aracatuba, Brazil
| | - M Mina
- Department of Pediatric Dentistry, Uconn Health, Farmington, CT, USA
| | - I Kalajzic
- Department of Reconstructive Sciences, Uconn Health, Farmington, CT, USA
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Abstract
Members of the fibroblast growth factor (FGF) family play essential and important roles in primary and reparative dentinogenesis, with conflicting results regarding their effects on odontoblast differentiation. Our recent studies showed that the effects of FGF2 on cells in odontoblast lineage were stage-specific and depended on the stage of cell maturity. Continuous exposure of pulp cells to FGF2 inhibited odontoblast differentiation, whereas early and limited exposure of pulp cells to FGF2 resulted in marked increases in odontoblast differentiation. The purpose of this study was to evaluate the cellular and molecular mechanisms regulating the inhibitory effects of FGF2 on odontoblast differentiation. To do so, we examined the effects of the addition of FGF2 during the differentiation/mineralization phase of the in vitro growth of pulp cultures derived from a series of green fluorescent protein reporter transgenic mice that display stage-specific activation of transgenes during odontoblast differentiation. Our results showed that this treatment first stimulated the differentiation of remaining progenitors in pulp cultures into functional odontoblasts but prevented their differentiation into mature odontoblasts. In addition, this treatment inhibited expression of markers of osteogenesis. Furthermore, we demonstrated that the inhibitory effects of FGF2 on odontoblast differentiation were mediated through activation of FGFR/MEK/Erk1/2 signaling and downregulation of bone morphogenetic protein signaling, with negative and positive roles in the expression of Dmp1 and Dspp, respectively, during the advanced stage of odontoblast differentiation.
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Affiliation(s)
- K Sagomonyants
- 1 Department of Oral Health and Diagnostic Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
| | - I Kalajzic
- 2 Department of Reconstructive Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
| | - P Maye
- 2 Department of Reconstructive Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
| | - M Mina
- 3 Department of Craniofacial Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
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Schincaglia G, Kim Y, Piva R, Sobue T, Torreggiani E, Kalajzic I. Osteogenesis During Early Healing Around Titanium and Roxolid Implants: Evaluation of Bone Markers by Immunohistochemistry and RT-PCR Analysis in Miniature Pigs: A Pilot Study. Int J Oral Maxillofac Implants 2017; 32:42-51. [DOI: 10.11607/jomi.4859] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Vidovic I, Banerjee A, Fatahi R, Matthews BG, Dyment NA, Kalajzic I, Mina M. αSMA-Expressing Perivascular Cells Represent Dental Pulp Progenitors In Vivo. J Dent Res 2016; 96:323-330. [PMID: 27834664 DOI: 10.1177/0022034516678208] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The goal of this study was to examine the contribution of perivascular cells to odontoblasts during the development, growth, and repair of dentin using mouse molars as a model. We used an inducible, Cre-loxP in vivo fate-mapping approach to examine the contributions of the descendants of cells expressing the αSMA-CreERT2 transgene to the odontoblast lineage. In vivo lineage-tracing experiments in molars showed the contribution of αSMA-tdTomato+ cells to a small number of newly formed odontoblasts during primary dentinogenesis. Using an experimental pulp exposure model in molars to induce reparative dentinogenesis, we demonstrate the contribution of αSMA-tdTomato+ cells to cells secreting reparative dentin. Our results demonstrate that αSMA-tdTomato+ cells differentiated into Col2.3-GFP+ cells composed of both Dspp+ odontoblasts and Bsp+ osteoblasts. Our findings identify a population of mesenchymal progenitor cells capable of giving rise to a second generation of odontoblasts during reparative dentinogenesis. This population also makes a small contribution to odontoblasts during primary dentinogenesis.
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Affiliation(s)
- I Vidovic
- 1 Department of Craniofacial Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
| | - A Banerjee
- 1 Department of Craniofacial Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
| | - R Fatahi
- 2 Department of Reconstructive Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
| | - B G Matthews
- 2 Department of Reconstructive Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
| | - N A Dyment
- 2 Department of Reconstructive Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
| | - I Kalajzic
- 2 Department of Reconstructive Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
| | - M Mina
- 1 Department of Craniofacial Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
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Abstract
Advancing our understanding of osteoblast biology and differentiation is critical to elucidate the pathological mechanisms responsible for skeletal diseases such as osteoporosis. Histology and histomorphometry, the classical methods to study osteoblast biology, identify osteoblasts based on their location and morphology and ability to mineralize matrix, but do not clearly define their stage of differentiation. Introduction of visual transgenes into the cells of osteoblast lineage has revolutionized the field and resulted in a paradigm shift that allowed for specific identification and isolation of subpopulations within the osteoblast lineage. Knowledge acquired from the studies based on GFP transgenes has allowed for more precise interpretation of studies analyzing targeted overexpression or deletion of genes in the osteoblast lineage. Here, we provide a condensed overview of the currently available promoter-fluorescent reporter transgenic mice that have been generated and evaluated to varying extents. We cover different stages of the lineage as transgenes have been utilized to identify osteoprogenitors, pre-osteoblasts, osteoblasts, or osteocytes. We show that each of these promoters present with advantages and disadvantages. The studies based on the use of these reporter mice have improved our understanding of bone biology. They constitute attractive models to target osteoblasts and help to understand their cell biology.
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Affiliation(s)
- Emilie Roeder
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, CT 06030, USA
| | - Brya G Matthews
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, CT 06030, USA
| | - Ivo Kalajzic
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, CT 06030, USA; Department of Pathophysiology, University of Osijek, Osijek, Croatia.
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Yoshida R, Alaee F, Dyrna F, Kronenberg MS, Maye P, Kalajzic I, Rowe DW, Mazzocca AD, Dyment NA. Murine supraspinatus tendon injury model to identify the cellular origins of rotator cuff healing. Connect Tissue Res 2016; 57:507-515. [PMID: 27184388 PMCID: PMC5149426 DOI: 10.1080/03008207.2016.1189910] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
UNLABELLED Purpose of this study: To elucidate the origin of cell populations that contribute to rotator cuff healing, we developed a mouse surgical model where a full-thickness, central detachment is created in the supraspinatus. MATERIALS AND METHODS Three different inducible Cre transgenic mice with Ai9-tdTomato reporter expression (PRG4-9, αSMA-9, and AGC-9) were used to label different cell populations in the shoulder. The defect was created surgically in the supraspinatus. The mice were injected with tamoxifen at surgery to label the cells and sacrificed at 1, 2, and 5 weeks postoperatively. Frozen sections were fluorescently imaged then stained with Toluidine Blue and re-imaged. RESULTS Three notable changes were apparent postoperatively. (1) A long thin layer of tissue formed on the bursal side overlying the supraspinatus tendon. (2) The tendon proximal to the defect initially became hypercellular and disorganized. (3) The distal stump at the insertion underwent minimal remodeling. In the uninjured shoulder, tdTomato expression was seen in the tendon midsubstance and paratenon cell on the bursal side in PRG4-9, in paratenon, blood vessels, and periosteum of acromion in SMA-9, and in articular cartilage, unmineralized fibrocartilage of supraspinatus enthesis, and acromioclavicular joint in AGC-9 mice. In the injured PRG4-9 and SMA-9 mice, the healing tissues contained an abundant number of tdTomato+ cells, while minimal contribution of tdTomato+ cells was seen in AGC-9 mice. CONCLUSIONS The study supports the importance of the bursal side of the tendon to rotator cuff healing and PRG4 and αSMA may be markers for these progenitor cells.
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Affiliation(s)
- Ryu Yoshida
- Department of Orthopaedic Surgery, University of Connecticut Health Center, Farmington, CT
| | - Farhang Alaee
- Department of Orthopaedic Surgery, University of Connecticut Health Center, Farmington, CT
| | - Felix Dyrna
- Department of Orthopaedic Surgery, University of Connecticut Health Center, Farmington, CT
| | - Mark S. Kronenberg
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, CT
| | - Peter Maye
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, CT
| | - Ivo Kalajzic
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, CT
| | - David W Rowe
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, CT
| | - Augustus D. Mazzocca
- Department of Orthopaedic Surgery, University of Connecticut Health Center, Farmington, CT
| | - Nathaniel A Dyment
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, CT
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Embree MC, Chen M, Pylawka S, Kong D, Iwaoka GM, Kalajzic I, Yao H, Shi C, Sun D, Sheu TJ, Koslovsky DA, Koch A, Mao JJ. Exploiting endogenous fibrocartilage stem cells to regenerate cartilage and repair joint injury. Nat Commun 2016; 7:13073. [PMID: 27721375 PMCID: PMC5062541 DOI: 10.1038/ncomms13073] [Citation(s) in RCA: 101] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 09/01/2016] [Indexed: 02/07/2023] Open
Abstract
Tissue regeneration using stem cell-based transplantation faces many hurdles. Alternatively, therapeutically exploiting endogenous stem cells to regenerate injured or diseased tissue may circumvent these challenges. Here we show resident fibrocartilage stem cells (FCSCs) can be used to regenerate and repair cartilage. We identify FCSCs residing within the superficial zone niche in the temporomandibular joint (TMJ) condyle. A single FCSC spontaneously generates a cartilage anlage, remodels into bone and organizes a haematopoietic microenvironment. Wnt signals deplete the reservoir of FCSCs and cause cartilage degeneration. We also show that intra-articular treatment with the Wnt inhibitor sclerostin sustains the FCSC pool and regenerates cartilage in a TMJ injury model. We demonstrate the promise of exploiting resident FCSCs as a regenerative therapeutic strategy to substitute cell transplantation that could be beneficial for patients suffering from fibrocartilage injury and disease. These data prompt the examination of utilizing this strategy for other musculoskeletal tissues. A potentially superior tissue regenerative strategy to stem cell transplantation is modulation of endogenous stem cells. Here the authors show fibrocartilage stem cells exist in the temporomandibular joint that contribute to cartilage regeneration and can be manipulated to enhance regeneration through canonical Wnt signalling.
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Affiliation(s)
- Mildred C Embree
- TMJ Biology and Regenerative Medicine Laboratory, College of Dental Medicine, Columbia University Medical Center, 630 W 168th St, P&S 16-440, New York, New York 10032, USA
| | - Mo Chen
- Center for Craniofacial Regeneration, College of Dental Medicine, Columbia University Medical Center, 622 W 168th St, New York, New York 10032, USA
| | - Serhiy Pylawka
- TMJ Biology and Regenerative Medicine Laboratory, College of Dental Medicine, Columbia University Medical Center, 630 W 168th St, P&S 16-440, New York, New York 10032, USA
| | - Danielle Kong
- Center for Craniofacial Regeneration, College of Dental Medicine, Columbia University Medical Center, 622 W 168th St, New York, New York 10032, USA
| | - George M Iwaoka
- Center for Craniofacial Regeneration, College of Dental Medicine, Columbia University Medical Center, 622 W 168th St, New York, New York 10032, USA
| | - Ivo Kalajzic
- Department of Reconstructive Sciences, MC3705, L7005, University of Connecticut Health Sciences Center, 263 Farmington Avenue, Farmington, Connecticut 06032, USA
| | - Hai Yao
- Clemson-MUSC Bioengineering Program, Department of Bioengineering, Clemson University, 173 Ashley Avenue, MSC 508, Charleston, South Carolina 29425, USA
| | - Chancheng Shi
- Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, 266 Fangzheng Avenue, Shuitu Hi-tech Industrial Park, Beibei District, Chongqing 400714, China
| | - Dongming Sun
- W.M. Keck Center for Collaborative Neuroscience, Rutgers, The State University of New Jersey, 604 Allison Road, D-251, Piscataway, New Jersey 08854, USA
| | - Tzong-Jen Sheu
- Center for Musculoskeletal Research, University of Rochester Medical Center, 601 Elmwood Avenue, Box 665, Rochester, New York 14620, USA
| | - David A Koslovsky
- Metropolitan Oral Surgery Associates, 488 Madison Avenue, #200, New York, New York 10022, USA
| | - Alia Koch
- College of Dental Medicine, Division of Oral and Maxillofacial Surgery, Columbia University Medical Center, 622 W 168th St, New York, New York 10032, USA
| | - Jeremy J Mao
- Center for Craniofacial Regeneration, College of Dental Medicine, Columbia University Medical Center, 622 W 168th St, New York, New York 10032, USA
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Matsumoto K, Xavier S, Chen J, Kida Y, Lipphardt M, Ikeda R, Gevertz A, Caviris M, Hatzopoulos AK, Kalajzic I, Dutton J, Ratliff BB, Zhao H, Darzynkiewicz Z, Rose‐John S, Goligorsky MS. Instructive Role of the Microenvironment in Preventing Renal Fibrosis. Stem Cells Transl Med 2016; 6:992-1005. [PMID: 28297566 PMCID: PMC5442777 DOI: 10.5966/sctm.2016-0095] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 08/24/2016] [Indexed: 12/26/2022] Open
Abstract
Accumulation of myofibroblasts is a hallmark of renal fibrosis. A significant proportion of myofibroblasts has been reported to originate via endothelial‐mesenchymal transition. We initially hypothesized that exposing myofibroblasts to the extract of endothelial progenitor cells (EPCs) could reverse this transition. Indeed, in vitro treatment of transforming growth factor‐β1 (TGF‐β1)‐activated fibroblasts with EPC extract prevented expression of α‐smooth muscle actin (α‐SMA); however, it did not enhance expression of endothelial markers. In two distinct models of renal fibrosis—unilateral ureteral obstruction and chronic phase of folic acid‐induced nephropathy—subcapsular injection of EPC extract to the kidney prevented and reversed accumulation of α‐SMA‐positive myofibroblasts and reduced fibrosis. Screening the composition of EPC extract for cytokines revealed that it is enriched in leukemia inhibitory factor (LIF) and vascular endothelial growth factor. Only LIF was capable of reducing fibroblast‐to‐myofibroblast transition of TGF‐β1‐activated fibroblasts. In vivo subcapsular administration of LIF reduced the number of myofibroblasts and improved the density of peritubular capillaries; however, it did not reduce the degree of fibrosis. A receptor‐independent ligand for the gp130/STAT3 pathway, hyper‐interleukin‐6 (hyper‐IL‐6), not only induced a robust downstream increase in pluripotency factors Nanog and c‐Myc but also exhibited a powerful antifibrotic effect. In conclusion, EPC extract prevented and reversed fibroblast‐to‐myofibroblast transition and renal fibrosis. The component of EPC extract, LIF, was capable of preventing development of the contractile phenotype of activated fibroblasts but did not eliminate TGF‐β1‐induced collagen synthesis in cultured fibroblasts and models of renal fibrosis, whereas a receptor‐independent gp130/STAT3 agonist, hyper‐IL‐6, prevented fibrosis. In summary, these studies, through the evolution from EPC extract to LIF and then to hyper‐IL‐6, demonstrate the instructive role of microenvironmental cues and may provide in the future a facile strategy to prevent and reverse renal fibrosis. Stem Cells Translational Medicine2017;6:992–1005
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Affiliation(s)
- Kei Matsumoto
- Department of Medicine, New York Medical College, Valhalla, New York, USA
- Department of Pharmacology, New York Medical College, Valhalla, New York, USA
- Department of Physiology, New York Medical College, Valhalla, New York, USA
- Department of Pathology, New York Medical College, Valhalla, New York, USA
- Renal Research Institute, New York Medical College, Valhalla, New York, USA
- Showa University, Tokyo, Japan
| | - Sandhya Xavier
- Department of Medicine, New York Medical College, Valhalla, New York, USA
- Department of Pharmacology, New York Medical College, Valhalla, New York, USA
- Department of Physiology, New York Medical College, Valhalla, New York, USA
- Department of Pathology, New York Medical College, Valhalla, New York, USA
- Renal Research Institute, New York Medical College, Valhalla, New York, USA
| | - Jun Chen
- Department of Medicine, New York Medical College, Valhalla, New York, USA
- Department of Pharmacology, New York Medical College, Valhalla, New York, USA
- Department of Physiology, New York Medical College, Valhalla, New York, USA
- Department of Pathology, New York Medical College, Valhalla, New York, USA
- Renal Research Institute, New York Medical College, Valhalla, New York, USA
| | - Yujiro Kida
- Department of Medicine, New York Medical College, Valhalla, New York, USA
- Department of Pharmacology, New York Medical College, Valhalla, New York, USA
- Department of Physiology, New York Medical College, Valhalla, New York, USA
- Department of Pathology, New York Medical College, Valhalla, New York, USA
- Renal Research Institute, New York Medical College, Valhalla, New York, USA
| | - Mark Lipphardt
- Department of Medicine, New York Medical College, Valhalla, New York, USA
- Department of Pharmacology, New York Medical College, Valhalla, New York, USA
- Department of Physiology, New York Medical College, Valhalla, New York, USA
- Department of Pathology, New York Medical College, Valhalla, New York, USA
- Renal Research Institute, New York Medical College, Valhalla, New York, USA
| | - Reina Ikeda
- Department of Medicine, New York Medical College, Valhalla, New York, USA
- Department of Pharmacology, New York Medical College, Valhalla, New York, USA
- Department of Physiology, New York Medical College, Valhalla, New York, USA
- Department of Pathology, New York Medical College, Valhalla, New York, USA
- Renal Research Institute, New York Medical College, Valhalla, New York, USA
- Okayama University, Okayama, Japan
| | - Annie Gevertz
- Department of Medicine, New York Medical College, Valhalla, New York, USA
- Department of Pharmacology, New York Medical College, Valhalla, New York, USA
- Department of Physiology, New York Medical College, Valhalla, New York, USA
- Department of Pathology, New York Medical College, Valhalla, New York, USA
- Renal Research Institute, New York Medical College, Valhalla, New York, USA
| | - Mario Caviris
- Department of Medicine, New York Medical College, Valhalla, New York, USA
- Department of Pharmacology, New York Medical College, Valhalla, New York, USA
- Department of Physiology, New York Medical College, Valhalla, New York, USA
- Department of Pathology, New York Medical College, Valhalla, New York, USA
- Renal Research Institute, New York Medical College, Valhalla, New York, USA
| | | | - Ivo Kalajzic
- University of Connecticut Health Center, Farmington, Connecticut, USA
| | - James Dutton
- Stem Cell Institute, University of Minnesota, Minneapolis, Minnesota, USA
| | - Brian B. Ratliff
- Department of Medicine, New York Medical College, Valhalla, New York, USA
- Department of Pharmacology, New York Medical College, Valhalla, New York, USA
- Department of Physiology, New York Medical College, Valhalla, New York, USA
- Department of Pathology, New York Medical College, Valhalla, New York, USA
- Renal Research Institute, New York Medical College, Valhalla, New York, USA
| | - Hong Zhao
- Department of Medicine, New York Medical College, Valhalla, New York, USA
- Department of Pharmacology, New York Medical College, Valhalla, New York, USA
- Department of Physiology, New York Medical College, Valhalla, New York, USA
- Department of Pathology, New York Medical College, Valhalla, New York, USA
- Renal Research Institute, New York Medical College, Valhalla, New York, USA
| | - Zbygniew Darzynkiewicz
- Department of Medicine, New York Medical College, Valhalla, New York, USA
- Department of Pharmacology, New York Medical College, Valhalla, New York, USA
- Department of Physiology, New York Medical College, Valhalla, New York, USA
- Department of Pathology, New York Medical College, Valhalla, New York, USA
- Renal Research Institute, New York Medical College, Valhalla, New York, USA
| | - Stefan Rose‐John
- Institute of Biochemistry, Christian‐Albrechts University, Kiel, Germany
| | - Michael S. Goligorsky
- Department of Medicine, New York Medical College, Valhalla, New York, USA
- Department of Pharmacology, New York Medical College, Valhalla, New York, USA
- Department of Physiology, New York Medical College, Valhalla, New York, USA
- Department of Pathology, New York Medical College, Valhalla, New York, USA
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Matic I, Matthews BG, Wang X, Dyment NA, Worthley DL, Rowe DW, Grcevic D, Kalajzic I. Quiescent Bone Lining Cells Are a Major Source of Osteoblasts During Adulthood. Stem Cells 2016; 34:2930-2942. [PMID: 27507737 DOI: 10.1002/stem.2474] [Citation(s) in RCA: 111] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Revised: 06/15/2016] [Accepted: 07/05/2016] [Indexed: 12/23/2022]
Abstract
The in vivo origin of bone-producing osteoblasts is not fully defined. Skeletal stem cells, a population of mesenchymal stem cells resident in the bone marrow compartment, are thought to act as osteoprogenitors during growth and adulthood. Quiescent bone lining cells (BLCs) have been suggested as a population capable of activation into mature osteoblasts. These cells were defined by location and their morphology and studies addressing their significance have been hampered by their inaccessibility, and lack of markers that would allow for their identification and tracing. Using lineage tracing models, we have observed labeled osteoblasts at time points extending beyond the reported lifespan for this cell type, suggesting continuous reactivation of BLCs. BLCs also make a major contribution to bone formation after osteoblast ablation, which includes the ability to proliferate. In contrast, mesenchymal progenitors labeled by Gremlin1 or alpha smooth muscle actin do not contribute to bone formation in this setting. BLC activation is inhibited by glucocorticoids, which represent a well-established cause of osteoporosis. BLCs express cell surface markers characteristic of mesenchymal stem/progenitors that are largely absent in osteoblasts including Sca1 and Leptin Receptor. BLCs also show different gene expression profiles to osteoblasts, including elevated expression of Mmp13, and osteoclast regulators RANKL and macrophage colony stimulating factor, and retain osteogenic potential upon transplantation. Our findings provide evidence that bone lining cells represent a major source of osteoblasts during adulthood. Stem Cells 2016;34:2930-2942.
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Affiliation(s)
- Igor Matic
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, Connecticut, USA
| | - Brya G Matthews
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, Connecticut, USA
| | - Xi Wang
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, Connecticut, USA
| | - Nathaniel A Dyment
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, Connecticut, USA
| | - Daniel L Worthley
- Department of Medicine and Cancer Theme, University of Adelaide & SAHMRI, Adelaide, South Australia, Australia
| | - David W Rowe
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, Connecticut, USA
| | - Danka Grcevic
- Department of Physiology and Immunology, School of Medicine, University of Zagreb, Zagreb, Croatia
| | - Ivo Kalajzic
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, Connecticut, USA
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Root SH, Matthews B, Kalajzic I, Aguila HL. Characterization of a novel bone marrow resident cell population with the potential to regulate early hematopoiesis and skeletogenesis. The Journal of Immunology 2016. [DOI: 10.4049/jimmunol.196.supp.52.9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Abstract
Hematopoiesis and skeletogenesis are tightly regulated with participation of cells from both systems. The main hematopoietic component is the osteoclast, a cell crucial for bone remodeling. However, beyond bone homeostasis, other hematopoietic cells may exist as regulators of hematopoiesis within the bone marrow (BM) microenvironment. Histological analyses of mice expressing cre under the control of Dental Matrix Protein-1 (Dmp-1) promoter and crossed with the reporter strain Ai9, showed a fluorescent (tomato+) dendritic cell–like population interspersed within the BM space. These tomato+ cells were isolated, and showed efficient expression of RANK-L and IL-7, suggesting that they could regulate hematopoiesis. These cells also express surface markers of myeloid lineage including: CD11b, F4.80, CD169, and Ly-6C. In vitro hematopoietic progression assays failed on generating these cells from isolated hematopoietic stem cells. However, they can be generated and expanded ex vivo from CD11b+ tomato negative cells. Furthermore, using a tamoxifen inducible Dmp-1/tomato mouse, hematopoietic tomato+ cells appeared 2 days after tamoxifen treatment. In a transgenic mouse bearing the tamoxifen inducible Dmp-1/tomato plus a transgene allowing the ablation of bone formation after injecting ganciclovir; bone ablation for 16 days followed by tamoxifen two days prior to analysis, showed a compromise in the generation of tomato+ hematopoietic cells indicating that their generation is linked to bone formation. Finally, these cells exist in the BM of late gestation embryos and neonates suggesting a possible fetal origin. Currently we are addressing their phagocytic function and their ability to influence hematopoietic progression.
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Matthews BG, Torreggiani E, Roeder E, Matic I, Grcevic D, Kalajzic I. Osteogenic potential of alpha smooth muscle actin expressing muscle resident progenitor cells. Bone 2016; 84:69-77. [PMID: 26721734 PMCID: PMC4755912 DOI: 10.1016/j.bone.2015.12.010] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Revised: 11/14/2015] [Accepted: 12/19/2015] [Indexed: 12/16/2022]
Abstract
Heterotopic ossification (HO) is a pathological process where bone forms in connective tissues such as skeletal muscle. Previous studies have suggested that muscle-resident non-myogenic mesenchymal progenitors are the likely source of osteoblasts and chondrocytes in HO. However, the previously identified markers of muscle-resident osteoprogenitors label up to half the osteoblasts within heterotopic lesions, suggesting other cell populations are involved. We have identified alpha smooth muscle actin (αSMA) as a marker of osteoprogenitor cells in bone and periodontium, and of osteo-chondro progenitors in the periosteum during fracture healing. We therefore utilized a lineage tracing approach to evaluate whether αSMACreERT2 identifies osteoprogenitors in the muscle. We show that in the muscle, αSMACreERT2 labels both perivascular cells, and satellite cells. αSMACre-labeled cells undergo osteogenic differentiation in vitro and form osteoblasts and chondrocytes in BMP2-induced HO in vivo. In contrast, Pax7CreERT2-labeled muscle satellite cells were restricted to myogenic differentiation in vitro, and rarely contributed to HO in vivo. Our data indicate that αSMACreERT2 labels a large proportion of osteoprogenitors in skeletal muscle, and therefore represents another marker of muscle-resident cells with osteogenic potential under HO-inducing stimulus. In contrast, muscle satellite cells make minimal contribution to bone formation in vivo.
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Affiliation(s)
- Brya G Matthews
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, CT, USA
| | - Elena Torreggiani
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, CT, USA
| | - Emilie Roeder
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, CT, USA
| | - Igor Matic
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, CT, USA
| | - Danka Grcevic
- Department of Physiology and Immunology, School of Medicine, University of Zagreb, Zagreb, Croatia
| | - Ivo Kalajzic
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, CT, USA.
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Kolind M, Bobyn JD, Matthews BG, Mikulec K, Aiken A, Little DG, Kalajzic I, Schindeler A. Lineage tracking of mesenchymal and endothelial progenitors in BMP-induced bone formation. Bone 2015; 81:53-59. [PMID: 26141839 PMCID: PMC4844190 DOI: 10.1016/j.bone.2015.06.023] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Revised: 06/26/2015] [Accepted: 06/29/2015] [Indexed: 11/29/2022]
Abstract
To better understand the relative contributions of mesenchymal and endothelial progenitor cells to rhBMP-2 induced bone formation, we examined the distribution of lineage-labeled cells in Tie2-Cre:Ai9 and αSMA-creERT2:Col2.3-GFP:Ai9 reporter mice. Established orthopedic models of ectopic bone formation in the hind limb and spine fusion were employed. Tie2-lineage cells were found extensively in the ectopic bone and spine fusion masses, but co-staining was only seen with tartrate-resistant acid phosphatase (TRAP) activity (osteoclasts) and CD31 immunohistochemistry (vascular endothelial cells), and not alkaline phosphatase (AP) activity (osteoblasts). To further confirm the lack of a functional contribution of Tie2-lineage cells to BMP-induced bone, we developed conditional knockout mice where Tie2-lineage cells are rendered null for key bone transcription factor osterix (Tie2-cre:Osx(fx/fx) mice). Conditional knockout mice showed no difference in BMP-induced bone formation compared to littermate controls. Pulse labeling of mesenchymal cells with Tamoxifen in mice undergoing spine fusion revealed that αSMA-lineage cells contributed to the osteoblastic lineage (Col2.3-GFP), but not to endothelial cells or osteoclast populations. These data indicate that the αSMA+ and Tie2+ progenitor lineages make distinct cellular contributions to bone formation, angiogenesis, and resorption/remodeling.
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Affiliation(s)
- Mille Kolind
- Centre for Children's Bone Health, The Children's Hospital at Westmead, Westmead, NSW, Australia
| | - Justin D Bobyn
- Centre for Children's Bone Health, The Children's Hospital at Westmead, Westmead, NSW, Australia; Discipline of Paediatrics and Child Health, Faculty of Medicine, University of Sydney, Sydney, NSW, Australia
| | - Brya G Matthews
- Department of Reconstructive Sciences, School of Dental Medicine, UConn Health, Farmington, CT, USA
| | - Kathy Mikulec
- Centre for Children's Bone Health, The Children's Hospital at Westmead, Westmead, NSW, Australia
| | - Alastair Aiken
- Centre for Children's Bone Health, The Children's Hospital at Westmead, Westmead, NSW, Australia
| | - David G Little
- Centre for Children's Bone Health, The Children's Hospital at Westmead, Westmead, NSW, Australia; Discipline of Paediatrics and Child Health, Faculty of Medicine, University of Sydney, Sydney, NSW, Australia
| | - Ivo Kalajzic
- Department of Reconstructive Sciences, School of Dental Medicine, UConn Health, Farmington, CT, USA
| | - Aaron Schindeler
- Centre for Children's Bone Health, The Children's Hospital at Westmead, Westmead, NSW, Australia; Discipline of Paediatrics and Child Health, Faculty of Medicine, University of Sydney, Sydney, NSW, Australia.
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Abstract
Members of the fibroblast growth factor (FGF) family play essential and important roles in primary and reparative dentinogenesis. Although there appears to be a general agreement on the effects of FGF signaling on the proliferation of pulp cells, there are conflicting results regarding its effects on odontoblast differentiation. We recently examined the effects of continuous exposure of dental pulp cells to FGF2 and showed that the effects of FGF2 on differentiation of progenitor cells into odontoblasts were stage specific and dependent on the stage of cell maturity. The purpose of this study was to gain further insight into cellular and molecular mechanisms regulating the stimulatory effects of FGF2 on odontoblast differentiation. To do so, we examined the effects of early and limited exposure of pulp cells from a series of green fluorescent protein (GFP) reporter transgenic mice that display stage-specific activation of transgenes during odontoblast differentiation to FGF2. Our results showed that early and limited exposure of pulp cells to FGF2 did not have significant effects on the extent of mineralization but induced significant increases in the expression of Dmp1 and Dspp and the number of DMP1-GFP(+) and DSPP-Cerulean(+) odontoblasts. Our results also showed that the stimulatory effects of FGF2 on odontoblast differentiation were mediated through FGFR/MEK/Erk1/2 signaling, increases in Bmp2, and activation of the BMP/BMPR signaling pathway. These observations show that early and limited exposure of pulp cells to FGF2 alone promotes odontoblast differentiation and provides critical insight for applications of FGF2 in dentin regeneration.
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Affiliation(s)
- K Sagomonyants
- Department of Craniofacial Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
| | - I Kalajzic
- Department of Reconstructive Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
| | - P Maye
- Department of Reconstructive Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
| | - M Mina
- Department of Craniofacial Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
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Matthews BG, Roguljic H, Franceschetti T, Roeder E, Matic I, Vidovic I, Joshi P, Kum KY, Kalajzic I. Gene-expression analysis of cementoblasts and osteoblasts. J Periodontal Res 2015. [PMID: 26215316 DOI: 10.1111/jre.12309] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND AND OBJECTIVE Cementum and bone are similar mineralized tissues, but cementum accumulates much more slowly than bone, does not have vasculature or innervation and does not undergo remodeling. Despite these differences, there are no well-established markers to distinguish cementoblasts from other mature mineralizing cells such as osteoblasts and odontoblasts. The purpose of this study was to assess differences in gene expression between cementoblasts and osteoblasts using gene profiling of cell populations isolated directly from osteocalcin-green fluorescent protein (OC-GFP) transgenic mice. MATERIAL AND METHODS OC-GFP reporter mice were used as they show labeling of cementoblasts, osteoblasts and odontoblasts, but not of periodontal ligament fibroblasts, within the periodontium. We sorted cells digested from the molar root surface to isolate OC-GFP(+) cementoblasts. Osteoblasts were isolated from calvarial digests. Microarray analysis was performed, and selected results were confirmed by real-time PCR and immunostaining or in situ hybridization. RESULTS Microarray analysis identified 95 genes that were expressed at least two-fold higher in cementoblasts than in osteoblasts. Our analysis indicated that the Wnt signaling pathway was differentially regulated, as were genes related to skeletal development. Real-time PCR confirmed that expression of the Wnt inhibitors Wnt inhibitory factor 1 (Wif1) and secreted frizzled-related protein 1 (Sfrp1) was elevated in cementoblasts compared with osteoblasts, and Wif1 expression was localized to the apical root region. In addition, the transcription factor BARX homeobox 1 (Barx1) was expressed at higher levels in cementoblasts, and immunohistochemistry indicated that BARX1 was expressed in apical cementoblasts and cementocytes, but not in osteoblasts or odontoblasts. CONCLUSION The OC-GFP mouse provides a good model for selectively isolating cementoblasts, and allowed for identification of differentially expressed genes between cementoblasts and osteoblasts.
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Affiliation(s)
- B G Matthews
- Department of Reconstructive Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
| | - H Roguljic
- Department of Reconstructive Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
| | - T Franceschetti
- Department of Reconstructive Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
| | - E Roeder
- Department of Reconstructive Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
| | - I Matic
- Department of Reconstructive Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
| | - I Vidovic
- Division of Pediatric Dentistry, Department of Craniofacial Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
| | - P Joshi
- Department of Computer Science and Engineering, University of Connecticut, Storrs, CT, USA
| | - K-Y Kum
- Division of endodontology, Department of Oral Health and Diagnostic Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA.,Department of Conservative Dentistry, Dental Research Institute, Seoul National University School of Dentistry, Seoul, Korea
| | - I Kalajzic
- Department of Reconstructive Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
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De Azevedo Queiroz I, Roeder E, Wang X, Matthews B, Gomes-Filho J, Kalajzic I. Effects of MTA on the osteogenic differentiation of murine BMSC. Dent Mater 2015. [DOI: 10.1016/j.dental.2015.08.102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Prater MD, Petit V, Alasdair Russell I, Giraddi RR, Shehata M, Menon S, Schulte R, Kalajzic I, Rath N, Olson MF, Metzger D, Faraldo MM, Deugnier MA, Glukhova MA, Stingl J. Mammary stem cells have myoepithelial cell properties. Nat Cell Biol 2014; 16:942-50, 1-7. [PMID: 25173976 PMCID: PMC4183554 DOI: 10.1038/ncb3025] [Citation(s) in RCA: 165] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Accepted: 07/10/2014] [Indexed: 01/17/2023]
Abstract
Contractile myoepithelial cells dominate the basal layer of the mammary epithelium and are considered to be differentiated cells. However, we observe that up to 54% of single basal cells can form colonies when seeded into adherent culture in the presence of agents that disrupt actin-myosin interactions, and on average, 65% of the single-cell-derived basal colonies can repopulate a mammary gland when transplanted in vivo. This indicates that a high proportion of basal myoepithelial cells can give rise to a mammary repopulating unit (MRU). We demonstrate that myoepithelial cells, flow-sorted using two independent myoepithelial-specific reporter strategies, have MRU capacity. Using an inducible lineage-tracing approach we follow the progeny of myoepithelial cells that express α-smooth muscle actin and show that they function as long-lived lineage-restricted stem cells in the virgin state and during pregnancy.
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MESH Headings
- Actins/metabolism
- Animals
- Benzamides/pharmacology
- Cell Proliferation/drug effects
- Cells, Cultured
- Dioxoles/pharmacology
- Epithelial Cells/cytology
- Epithelial Cells/metabolism
- Female
- Flow Cytometry
- Gene Expression Profiling
- Green Fluorescent Proteins/genetics
- Green Fluorescent Proteins/metabolism
- Interleukin Receptor Common gamma Subunit/deficiency
- Interleukin Receptor Common gamma Subunit/genetics
- Mammary Glands, Animal/cytology
- Mammary Glands, Animal/metabolism
- Mice, Inbred C57BL
- Mice, Inbred CBA
- Mice, Inbred NOD
- Mice, SCID
- Mice, Transgenic
- Microscopy, Fluorescence
- Myocytes, Smooth Muscle/cytology
- Myocytes, Smooth Muscle/metabolism
- Oligonucleotide Array Sequence Analysis
- Receptors, Transforming Growth Factor beta/antagonists & inhibitors
- Receptors, Transforming Growth Factor beta/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Stem Cells/cytology
- Stem Cells/metabolism
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Affiliation(s)
- Michael D Prater
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge CB2 0RE, UK
| | - Valérie Petit
- 1] Institut Curie, Centre de Recherche, Paris, F-75248, France [2] CNRS, UMR144, Paris, F-75248, France
| | - I Alasdair Russell
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge CB2 0RE, UK
| | - Rajshekhar R Giraddi
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge CB2 0RE, UK
| | - Mona Shehata
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge CB2 0RE, UK
| | - Suraj Menon
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge CB2 0RE, UK
| | - Reiner Schulte
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge CB2 0RE, UK
| | - Ivo Kalajzic
- Reconstructive Sciences, University of Connecticut Health Center, 263 Farmington Avenue, Farmington, Connecticut 06030-3705, USA
| | - Nicola Rath
- The Beatson Institute for Cancer Research, Garscube Estate, Switchback Road, Bearsden, Glasgow G61 1BD, UK
| | - Michael F Olson
- The Beatson Institute for Cancer Research, Garscube Estate, Switchback Road, Bearsden, Glasgow G61 1BD, UK
| | - Daniel Metzger
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, (CNRS/INSERM/Université de Strasbourg/Collège de France), Illkirch Cedex 67404, France
| | - Marisa M Faraldo
- 1] Institut Curie, Centre de Recherche, Paris, F-75248, France [2] CNRS, UMR144, Paris, F-75248, France
| | - Marie-Ange Deugnier
- 1] Institut Curie, Centre de Recherche, Paris, F-75248, France [2] CNRS, UMR144, Paris, F-75248, France
| | - Marina A Glukhova
- 1] Institut Curie, Centre de Recherche, Paris, F-75248, France [2] CNRS, UMR144, Paris, F-75248, France
| | - John Stingl
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge CB2 0RE, UK
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Li X, Garcia J, Lu J, Iriana S, Kalajzic I, Rowe D, Demer LL, Tintut Y. Roles of parathyroid hormone (PTH) receptor and reactive oxygen species in hyperlipidemia-induced PTH resistance in preosteoblasts. J Cell Biochem 2014; 115:179-88. [PMID: 24038594 DOI: 10.1002/jcb.24648] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2013] [Accepted: 08/13/2013] [Indexed: 11/08/2022]
Abstract
Bioactive lipids initiate inflammatory reactions leading to pathogenesis of atherosclerosis. Evidence shows that they also contribute to bone loss by inhibiting parathyroid hormone receptor (PTH1R) expression and differentiation of osteoblasts. We previously demonstrated that bone anabolic effects of PTH(1-34) are blunted in hyperlipidemic mice and that these PTH effects are restored by antioxidants. However, it is not clear which osteoblastic cell developmental stage is targeted by bioactive lipids. To investigate the effects of hyperlipidemia at the cellular level, hyperlipidemic Ldlr(-/-) mice were bred with Col3.6GFPtpz mice, in which preosteoblasts/osteoblasts carry a topaz fluorescent label, and with Col2.3GFPcyan mice, in which more mature osteoblasts/osteocytes carry a cyan fluorescent label. Histological analyses of trabecular bone surfaces in femoral as well as calvarial bones showed that intermittent PTH(1-34) increased fluorescence intensity in WT-Tpz mice, but not in Tpz-Ldlr(-/-) mice. In contrast, PTH(1-34) did not alter fluorescence intensity in femoral cortical envelopes of either WT-Cyan or Ldlr(-/-)-Cyan mice. To test the mechanism of PTH1R downregulation, preosteoblastic MC3T3-E1 cells were treated with bioactive lipids and the antioxidant Trolox. Results showed that inhibitory effects of PTH1R levels by bioactive lipids were rescued by pretreatment with Trolox. The inhibitory effects on expression of PTH1R as well as on PTH-induced osteoblastic genes were mimicked by xanthine/xanthine oxidase, a known generator of reactive oxygen species. These findings suggest an important role of the preosteoblastic development stage as the target and downregulation of PTH receptor expression mediated by intracellular oxidant stress as a mechanism in hyperlipidemia-induced PTH resistance.
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Affiliation(s)
- Xin Li
- Department of Medicine, University of California, Los Angeles, California
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50
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Dyment NA, Hagiwara Y, Matthews BG, Li Y, Kalajzic I, Rowe DW. Lineage tracing of resident tendon progenitor cells during growth and natural healing. PLoS One 2014; 9:e96113. [PMID: 24759953 PMCID: PMC3997569 DOI: 10.1371/journal.pone.0096113] [Citation(s) in RCA: 107] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Accepted: 04/02/2014] [Indexed: 02/07/2023] Open
Abstract
Unlike during embryogenesis, the identity of tissue resident progenitor cells that contribute to postnatal tendon growth and natural healing is poorly characterized. Therefore, we utilized 1) an inducible Cre driven by alpha smooth muscle actin (SMACreERT2), that identifies mesenchymal progenitors, 2) a constitutively active Cre driven by growth and differentiation factor 5 (GDF5Cre), a critical regulator of joint condensation, in combination with 3) an Ai9 Cre reporter to permanently label SMA9 and GDF5-9 populations and their progeny. In growing mice, SMA9+ cells were found in peritendinous structures and scleraxis-positive (ScxGFP+) cells within the tendon midsubstance and myotendinous junction. The progenitors within the tendon midsubstance were transiently labeled as they displayed a 4-fold expansion from day 2 to day 21 but reduced to baseline levels by day 70. SMA9+ cells were not found within tendon entheses or ligaments in the knee, suggesting a different origin. In contrast to the SMA9 population, GDF5-9+ cells extended from the bone through the enthesis and into a portion of the tendon midsubstance. GDF5-9+ cells were also found throughout the length of the ligaments, indicating a significant variation in the progenitors that contribute to tendons and ligaments. Following tendon injury, SMA9+ paratenon cells were the main contributors to the healing response. SMA9+ cells extended over the defect space at 1 week and differentiated into ScxGFP+ cells at 2 weeks, which coincided with increased collagen signal in the paratenon bridge. Thus, SMA9-labeled cells represent a unique progenitor source that contributes to the tendon midsubstance, paratenon, and myotendinous junction during growth and natural healing, while GDF5 progenitors contribute to tendon enthesis and ligament development. Understanding the mechanisms that regulate the expansion and differentiation of these progenitors may prove crucial to improving future repair strategies.
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Affiliation(s)
- Nathaniel A. Dyment
- Department of Reconstructive Sciences, College of Dental Medicine, University of Connecticut Health Center, Farmington, Connecticut, United States of America
| | - Yusuke Hagiwara
- Department of Reconstructive Sciences, College of Dental Medicine, University of Connecticut Health Center, Farmington, Connecticut, United States of America
| | - Brya G. Matthews
- Department of Reconstructive Sciences, College of Dental Medicine, University of Connecticut Health Center, Farmington, Connecticut, United States of America
| | - Yingcui Li
- Department of Reconstructive Sciences, College of Dental Medicine, University of Connecticut Health Center, Farmington, Connecticut, United States of America
- Department of Biology, College of Arts and Sciences, University of Hartford, Hartford, Connecticut, United States of America
| | - Ivo Kalajzic
- Department of Reconstructive Sciences, College of Dental Medicine, University of Connecticut Health Center, Farmington, Connecticut, United States of America
| | - David W. Rowe
- Department of Reconstructive Sciences, College of Dental Medicine, University of Connecticut Health Center, Farmington, Connecticut, United States of America
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