1
|
Jeffery EC. The role of hematopoiesis in bone repair: an update. Curr Opin Hematol 2024; 31:163-167. [PMID: 38723188 DOI: 10.1097/moh.0000000000000821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2024]
Abstract
PURPOSE OF REVIEW The repair of bone after injury requires the participation of many different immune cell populations, which are derived from the hematopoietic lineage. The field of osteoimmunology, or the study of the interactions between bone and the immune system, is a growing field with emerging impact on both the basic science and clinical aspects of fracture healing. RECENT FINDINGS Despite previous focus on the innate immune system in fracture healing, recent studies have revealed an important role for the adaptive immune system in bone repair. The composition of adaptive and innate immune cell populations present at the fracture site is significantly altered during aging and diet-induced obesity, which may contribute to delayed healing. Recent data also suggest a complicated relationship between fracture repair and systemic inflammation, raising the possibility that immune populations from distant sites such as the gut can impact the bone repair process. SUMMARY These findings have important implications for the treatment of fracture patients with antibiotics or anti-inflammatory drugs. Furthermore, the effects of systemic inflammation on fracture repair in the contexts of aging or obesity should be carefully interpreted, as they may not be uniformly detrimental.
Collapse
Affiliation(s)
- Elise C Jeffery
- Children's Research Institute, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| |
Collapse
|
2
|
Etschmaier V, Üçal M, Lohberger B, Weinberg A, Schäfer U. Ex vivo organotypic bone slice culture reveals preferential chondrogenesis after sustained growth plate injury. Cells Dev 2024:203927. [PMID: 38740089 DOI: 10.1016/j.cdev.2024.203927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 02/21/2024] [Accepted: 05/10/2024] [Indexed: 05/16/2024]
Abstract
Postnatal bone growth primarily relies on chondrocyte proliferation and osteogenic differentiation within the growth plate (GP) via endochondral ossification. Despite its importance, the GP is vulnerable to injuries, affecting 15-30 % of bone fractures. These injuries may lead to growth discrepancies, influence bone length and shape, and negatively affecting the patient's quality of life. This study aimed to investigate the molecular and cellular physiological and pathophysiological regeneration following sustained growth plate injury (GPI) in an ex vivo rat femur organotypic culture (OTC) model. Specifically, focusing on postnatal endochondral ossification process. 300 μm thick ex vivo bone cultures with a 2 mm long horizontal GPI was utilized. After 15 days of cultivation, gene expression analysis, histological and immunohistochemistry staining's were conducted to analyze key markers of endochondral ossification. In our OTCs we observed a significant increase in Sox9 expression due to GPI at day 15. The Ihh-PTHrP feedback loop was affected, favoring chondrocyte proliferation and maturation. Ihh levels increased significantly on day 7 and day 15, while PTHrP was downregulated on day 7. GPI had no impact on osteoclast number and activity, but gene expression analysis indicated OTCs' efforts to inhibit osteoclast differentiation and activation, thereby reducing bone resorption. In conclusion, our study provides novel insights into the molecular and cellular mechanisms underlying postnatal bone growth and regeneration following growth plate injury (GPI). We demonstrate that chondrocyte proliferation and differentiation play pivotal roles in the regeneration process, with the Ihh-PTHrP feedback loop modulating these processes. Importantly, our ex vivo rat femur organotypic culture model allows for the detailed investigation of these processes, providing a valuable tool for future research in the field of skeletal biology and regenerative medicine.
Collapse
Affiliation(s)
- Vanessa Etschmaier
- Department of Orthopaedics and Trauma, Medical University Graz, 8036 Graz, Austria.
| | - Muammer Üçal
- Department of Neurosurgery, Research Unit for Experimental Neurotraumatology, Medical University of Graz, 8036 Graz, Austria; Bio-Tech-Med Graz, 8010 Graz, Austria.
| | - Birgit Lohberger
- Department of Orthopaedics and Trauma, Medical University Graz, 8036 Graz, Austria.
| | - Annelie Weinberg
- Department of Orthopaedics and Trauma, Medical University Graz, 8036 Graz, Austria.
| | - Ute Schäfer
- Department of Neurosurgery, Research Unit for Experimental Neurotraumatology, Medical University of Graz, 8036 Graz, Austria.
| |
Collapse
|
3
|
Han J, Rindone AN, Elisseeff JH. Immunoengineering Biomaterials for Musculoskeletal Tissue Repair across Lifespan. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024:e2311646. [PMID: 38416061 DOI: 10.1002/adma.202311646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 01/23/2024] [Indexed: 02/29/2024]
Abstract
Musculoskeletal diseases and injuries are among the leading causes of pain and morbidity worldwide. Broad efforts have focused on developing pro-regenerative biomaterials to treat musculoskeletal conditions; however, these approaches have yet to make a significant clinical impact. Recent studies have demonstrated that the immune system is central in orchestrating tissue repair and that targeting pro-regenerative immune responses can improve biomaterial therapeutic outcomes. However, aging is a critical factor negatively affecting musculoskeletal tissue repair and immune function. Hence, understanding how age affects the response to biomaterials is essential for improving musculoskeletal biomaterial therapies. This review focuses on the intersection of the immune system and aging in response to biomaterials for musculoskeletal tissue repair. The article introduces the general impacts of aging on tissue physiology, the immune system, and the response to biomaterials. Then, it explains how the adaptive immune system guides the response to injury and biomaterial implants in cartilage, muscle, and bone and discusses how aging impacts these processes in each tissue type. The review concludes by highlighting future directions for the development and translation of personalized immunomodulatory biomaterials for musculoskeletal tissue repair.
Collapse
Affiliation(s)
- Jin Han
- Translational Tissue Engineering Center, Wilmer Eye Institute and Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, 21231, USA
| | - Alexandra N Rindone
- Translational Tissue Engineering Center, Wilmer Eye Institute and Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, 21231, USA
| | - Jennifer H Elisseeff
- Translational Tissue Engineering Center, Wilmer Eye Institute and Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, 21231, USA
- Bloomberg-Kimmel Institute for Cancer Immunotherapy, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD, 21231, USA
| |
Collapse
|
4
|
Capobianco CA, Hankenson KD, Knights AJ. Temporal dynamics of immune-stromal cell interactions in fracture healing. Front Immunol 2024; 15:1352819. [PMID: 38455063 PMCID: PMC10917940 DOI: 10.3389/fimmu.2024.1352819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Accepted: 02/06/2024] [Indexed: 03/09/2024] Open
Abstract
Bone fracture repair is a complex, multi-step process that involves communication between immune and stromal cells to coordinate the repair and regeneration of damaged tissue. In the US, 10% of all bone fractures do not heal properly without intervention, resulting in non-union. Complications from non-union fractures are physically and financially debilitating. We now appreciate the important role that immune cells play in tissue repair, and the necessity of the inflammatory response in initiating healing after skeletal trauma. The temporal dynamics of immune and stromal cell populations have been well characterized across the stages of fracture healing. Recent studies have begun to untangle the intricate mechanisms driving the immune response during normal or atypical, delayed healing. Various in vivo models of fracture healing, including genetic knockouts, as well as in vitro models of the fracture callus, have been implemented to enable experimental manipulation of the heterogeneous cellular environment. The goals of this review are to (1): summarize our current understanding of immune cell involvement in fracture healing (2); describe state-of-the art approaches to study inflammatory cells in fracture healing, including computational and in vitro models; and (3) identify gaps in our knowledge concerning immune-stromal crosstalk during bone healing.
Collapse
Affiliation(s)
- Christina A. Capobianco
- Department of Orthopaedic Surgery, University of Michigan, Ann Arbor, MI, United States
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States
| | - Kurt D. Hankenson
- Department of Orthopaedic Surgery, University of Michigan, Ann Arbor, MI, United States
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States
| | - Alexander J. Knights
- Department of Orthopaedic Surgery, University of Michigan, Ann Arbor, MI, United States
| |
Collapse
|
5
|
Schlundt C, Saß RA, Bucher CH, Bartosch S, Hauser AE, Volk HD, Duda GN, Schmidt-Bleek K. Complex Spatio-Temporal Interplay of Distinct Immune and Bone Cell Subsets during Bone Fracture Healing. Cells 2023; 13:40. [PMID: 38201244 PMCID: PMC10777943 DOI: 10.3390/cells13010040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 12/15/2023] [Accepted: 12/22/2023] [Indexed: 01/12/2024] Open
Abstract
BACKGROUND The healing of a bone injury is a highly complex process involving a multitude of different tissue and cell types, including immune cells, which play a major role in the initiation and progression of bone regeneration. METHODS We histologically analyzed the spatio-temporal occurrence of cells of the innate immune system (macrophages), the adaptive immune system (B and T lymphocytes), and bone cells (osteoblasts and osteoclasts) in the fracture area of a femoral osteotomy over the healing time. This study was performed in a bone osteotomy gap mouse model. We also investigated two key challenges of successful bone regeneration: hypoxia and revascularization. RESULTS Macrophages were present in and around the fracture gap throughout the entire healing period. The switch from initially pro-inflammatory M1 macrophages to the anti-inflammatory M2 phenotype coincided with the revascularization as well as the appearance of osteoblasts in the fracture area. This indicates that M2 macrophages are necessary for the restoration of vessels and that they also play an orchestrating role in osteoblastogenesis during bone healing. The presence of adaptive immune cells throughout the healing process emphasizes their essential role for regenerative processes that exceeds a mere pathogen defense. B and T cells co-localize consistently with bone cells throughout the healing process, consolidating their crucial role in guiding bone formation. These histological data provide, for the first time, comprehensive information about the complex interrelationships of the cellular network during the entire bone healing process in one standardized set up. With this, an overall picture of the spatio-temporal interplay of cellular key players in a bone healing scenario has been created. CONCLUSIONS A spatio-temporal distribution of immune cells, bone cells, and factors driving bone healing at time points that are decisive for this process-especially during the initial steps of inflammation and revascularization, as well as the soft and hard callus phases-has been visualized. The results show that the bone healing cascade does not consist of five distinct, consecutive phases but is a rather complex interrelated and continuous process of events, especially at the onset of healing.
Collapse
Affiliation(s)
- Claudia Schlundt
- Julius Wolff Institut, BIH at Charité—Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany; (C.S.); (R.A.S.); (C.H.B.); (G.N.D.)
- BIH Center for Regenerative Therapies, BIH at Charité—Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany;
| | - Radost A. Saß
- Julius Wolff Institut, BIH at Charité—Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany; (C.S.); (R.A.S.); (C.H.B.); (G.N.D.)
- BIH Center for Regenerative Therapies, BIH at Charité—Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany;
| | - Christian H. Bucher
- Julius Wolff Institut, BIH at Charité—Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany; (C.S.); (R.A.S.); (C.H.B.); (G.N.D.)
- BIH Center for Regenerative Therapies, BIH at Charité—Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany;
| | - Sabine Bartosch
- Berlin School for Regenerative Therapies, Charité—Universitätsmedizin Berlin, Augustenburger Plarz 1, 13353 Berlin, Germany;
| | - Anja E. Hauser
- Rheumatology and Clinical Immunology, Charité—Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany;
- Immune Dynamics, Deutsches Rheuma-Forschungszentrum Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Hans-Dieter Volk
- BIH Center for Regenerative Therapies, BIH at Charité—Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany;
- Institute of Medical Immunology, Charité—Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Georg N. Duda
- Julius Wolff Institut, BIH at Charité—Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany; (C.S.); (R.A.S.); (C.H.B.); (G.N.D.)
- BIH Center for Regenerative Therapies, BIH at Charité—Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany;
| | - Katharina Schmidt-Bleek
- Julius Wolff Institut, BIH at Charité—Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany; (C.S.); (R.A.S.); (C.H.B.); (G.N.D.)
- BIH Center for Regenerative Therapies, BIH at Charité—Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany;
| |
Collapse
|
6
|
Borgiani E, Nasello G, Ory L, Herpelinck T, Groeneveldt L, Bucher CH, Schmidt-Bleek K, Geris L. COMMBINI: an experimentally-informed COmputational Model of Macrophage dynamics in the Bone INjury Immunoresponse. Front Immunol 2023; 14:1231329. [PMID: 38130715 PMCID: PMC10733790 DOI: 10.3389/fimmu.2023.1231329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 10/11/2023] [Indexed: 12/23/2023] Open
Abstract
Bone fracture healing is a well-orchestrated but complex process that involves numerous regulations at different scales. This complexity becomes particularly evident during the inflammatory stage, as immune cells invade the healing region and trigger a cascade of signals to promote a favorable regenerative environment. Thus, the emergence of criticalities during this stage might hinder the rest of the process. Therefore, the investigation of the many interactions that regulate the inflammation has a primary importance on the exploration of the overall healing progression. In this context, an in silico model named COMMBINI (COmputational Model of Macrophage dynamics in the Bone INjury Immunoresponse) has been developed to investigate the mechano-biological interactions during the early inflammatory stage at the tissue, cellular and molecular levels. An agent-based model is employed to simulate the behavior of immune cells, inflammatory cytokines and fracture debris as well as their reciprocal multiscale biological interactions during the development of the early inflammation (up to 5 days post-injury). The strength of the computational approach is the capacity of the in silico model to simulate the overall healing process by taking into account the numerous hidden events that contribute to its success. To calibrate the model, we present an in silico immunofluorescence method that enables a direct comparison at the cellular level between the model output and experimental immunofluorescent images. The combination of sensitivity analysis and a Genetic Algorithm allows dynamic cooperation between these techniques, enabling faster identification of the most accurate parameter values, reducing the disparity between computer simulation and histological data. The sensitivity analysis showed a higher sensibility of the computer model to the macrophage recruitment ratio during the early inflammation and to proliferation in the late stage. Furthermore, the Genetic Algorithm highlighted an underestimation of macrophage proliferation by in vitro experiments. Further experiments were conducted using another externally fixated murine model, providing an independent validation dataset. The validated COMMBINI platform serves as a novel tool to deepen the understanding of the intricacies of the early bone regeneration phases. COMMBINI aims to contribute to designing novel treatment strategies in both the biological and mechanical domains.
Collapse
Affiliation(s)
- Edoardo Borgiani
- Biomechanics Research Unit, GIGA-In Silico Medicine, University of Liège, Liège, Belgium
- Prometheus, Division of Skeletal Tissue Engineering, KU Leuven, Leuven, Belgium
- Division of Biomechanics, Department of Mechanical Engineering, KU Leuven, Leuven, Belgium
| | - Gabriele Nasello
- Prometheus, Division of Skeletal Tissue Engineering, KU Leuven, Leuven, Belgium
- Skeletal Biology and Engineering Research Center, KU Leuven, Leuven, Belgium
| | - Liesbeth Ory
- Prometheus, Division of Skeletal Tissue Engineering, KU Leuven, Leuven, Belgium
- Skeletal Biology and Engineering Research Center, KU Leuven, Leuven, Belgium
| | - Tim Herpelinck
- Prometheus, Division of Skeletal Tissue Engineering, KU Leuven, Leuven, Belgium
- Skeletal Biology and Engineering Research Center, KU Leuven, Leuven, Belgium
| | - Lisanne Groeneveldt
- Prometheus, Division of Skeletal Tissue Engineering, KU Leuven, Leuven, Belgium
- Skeletal Biology and Engineering Research Center, KU Leuven, Leuven, Belgium
- Department of Cell Biology, Erasmus University Medical Center, Rotterdam, Netherlands
| | - Christian H. Bucher
- Julius Wolff Institute, Berlin Institute of Health, Charitè – Universitätsmedizin Berlin, Berlin, Germany
| | - Katharina Schmidt-Bleek
- Julius Wolff Institute, Berlin Institute of Health, Charitè – Universitätsmedizin Berlin, Berlin, Germany
| | - Liesbet Geris
- Biomechanics Research Unit, GIGA-In Silico Medicine, University of Liège, Liège, Belgium
- Prometheus, Division of Skeletal Tissue Engineering, KU Leuven, Leuven, Belgium
- Division of Biomechanics, Department of Mechanical Engineering, KU Leuven, Leuven, Belgium
- Skeletal Biology and Engineering Research Center, KU Leuven, Leuven, Belgium
| |
Collapse
|
7
|
Heyland M, Deppe D, Reisener MJ, Damm P, Taylor WR, Reinke S, Duda GN, Trepczynski A. Lower-limb internal loading and potential consequences for fracture healing. Front Bioeng Biotechnol 2023; 11:1284091. [PMID: 37901836 PMCID: PMC10602681 DOI: 10.3389/fbioe.2023.1284091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2023] [Accepted: 10/02/2023] [Indexed: 10/31/2023] Open
Abstract
Introduction: Mechanical loading is known to determine the course of bone fracture healing. We hypothesise that lower limb long bone loading differs with knee flexion angle during walking and frontal knee alignment, which affects fracture healing success. Materials and methods: Using our musculoskeletal in silico modelling constrained against in vivo data from patients with instrumented knee implants allowed us to assess internal loads in femur and tibia. These internal forces were associated with the clinical outcome of fracture healing in a relevant cohort of 178 extra-articular femur and tibia fractures in patients using a retrospective approach. Results: Mean peak forces differed with femoral compression (1,330-1,936 N at mid-shaft) amounting to about half of tibial compression (2,299-5,224 N). Mean peak bending moments in the frontal plane were greater in the femur (71-130 Nm) than in the tibia (from 26 to 43 Nm), each increasing proximally. Bending in the sagittal plane showed smaller mean peak bending moments in the femur (-38 to 43 Nm) reaching substantially higher values in the tibia (-63 to -175 Nm) with a peak proximally. Peak torsional moments had opposite directions for the femur (-13 to -40 Nm) versus tibia (15-48 Nm) with an increase towards the proximal end in both. Femoral fractures showed significantly lower scores in the modified Radiological Union Scale for Tibia (mRUST) at last follow-up (p < 0.001) compared to tibial fractures. Specifically, compression (r = 0.304), sagittal bending (r = 0.259), and frontal bending (r = -0.318) showed strong associations (p < 0.001) to mRUST at last follow-up. This was not the case for age, body weight, or localisation alone. Discussion: This study showed that moments in femur and tibia tend to decrease towards their distal ends. Tibial load components were influenced by knee flexion angle, especially at push-off, while static frontal alignment played a smaller role. Our results indicate that femur and tibia are loaded differently and thus require adapted fracture fixation considering load components rather than just overall load level.
Collapse
Affiliation(s)
- Mark Heyland
- Julius Wolff Institute, Berlin Institute of Health at Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - Dominik Deppe
- Julius Wolff Institute, Berlin Institute of Health at Charité—Universitätsmedizin Berlin, Berlin, Germany
- Department of Radiology, Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - Marie Jacqueline Reisener
- Julius Wolff Institute, Berlin Institute of Health at Charité—Universitätsmedizin Berlin, Berlin, Germany
- Centre for Muskuloskeletal Surgery (CMSC), Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - Philipp Damm
- Julius Wolff Institute, Berlin Institute of Health at Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - William R. Taylor
- Laboratory for Movement Biomechanics, ETH Zürich, Zürich, Switzerland
| | - Simon Reinke
- Julius Wolff Institute, Berlin Institute of Health at Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - Georg N. Duda
- Julius Wolff Institute, Berlin Institute of Health at Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - Adam Trepczynski
- Julius Wolff Institute, Berlin Institute of Health at Charité—Universitätsmedizin Berlin, Berlin, Germany
| |
Collapse
|
8
|
Khajuria DK, Reider I, Kamal F, Norbury CC, Elbarbary RA. Distinct defects in early innate and late adaptive immune responses typify impaired fracture healing in diet-induced obesity. Front Immunol 2023; 14:1250309. [PMID: 37854593 PMCID: PMC10579581 DOI: 10.3389/fimmu.2023.1250309] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Accepted: 08/25/2023] [Indexed: 10/20/2023] Open
Abstract
Bone fractures, the most common musculoskeletal injuries, heal through three main phases: inflammatory, repair, and remodeling. Around 10% of fracture patients suffer from impaired healing that requires surgical intervention, a huge burden on the healthcare system. The rate of impaired healing increases with metabolic diseases such as obesity-associated hyperglycemia/type 2 diabetes (T2D), an increasing concern given the growing incidence of obesity/T2D. Immune cells play pivotal roles in fracture healing, and obesity/T2D is associated with defective immune-cell functions. However, there is a gap in knowledge regarding the stoichiometry of immune cells that populate the callus and how that population changes during different phases of healing. Here, we used complementary global and single-cell techniques to characterize the repertoire of immune cells in the fracture callus and to identify populations specifically enriched in the fracture callus relative to the unfractured bone or bone marrow. Our analyses identified two clear waves of immune-cell infiltration into the callus: the first wave occurs during the early inflammatory phase of fracture healing, while the second takes place during the late repair/early remodeling phase, which is consistent with previous publications. Comprehensive analysis of each wave revealed that innate immune cells were activated during the early inflammatory phase, but in later phases they returned to homeostatic numbers and activation levels. Of the innate immune cells, distinct subsets of activated dendritic cells were particularly enriched in the inflammatory healing hematoma. In contrast to innate cells, lymphocytes, including B and T cells, were enriched and activated in the callus primarily during the late repair phase. The Diet-Induced Obesity (DIO) mouse, an established model of obesity-associated hyperglycemia and insulin resistance, suffers from multiple healing defects. Our data demonstrate that DIO mice exhibit dysregulated innate immune responses during the inflammatory phase, and defects in all lymphocyte compartments during the late repair phase. Taken together, our data characterize, for the first time, immune populations that are enriched/activated in the callus during two distinct phases of fracture healing and identify defects in the healing-associated immune response in DIO mice, which will facilitate future development of immunomodulatory therapeutics for impaired fracture healing.
Collapse
Affiliation(s)
- Deepak Kumar Khajuria
- Department of Orthopaedics and Rehabilitation, The Pennsylvania State University College of Medicine, Hershey, PA, United States
- Center for Orthopaedic Research and Translational Science (CORTS), The Pennsylvania State University College of Medicine, Hershey, PA, United States
| | - Irene Reider
- Department of Microbiology and Immunology, The Pennsylvania State University College of Medicine, Hershey, PA, United States
| | - Fadia Kamal
- Department of Orthopaedics and Rehabilitation, The Pennsylvania State University College of Medicine, Hershey, PA, United States
- Center for Orthopaedic Research and Translational Science (CORTS), The Pennsylvania State University College of Medicine, Hershey, PA, United States
- Department of Pharmacology, The Pennsylvania State University College of Medicine, Hershey, PA, United States
| | - Christopher C. Norbury
- Department of Microbiology and Immunology, The Pennsylvania State University College of Medicine, Hershey, PA, United States
| | - Reyad A. Elbarbary
- Department of Orthopaedics and Rehabilitation, The Pennsylvania State University College of Medicine, Hershey, PA, United States
- Center for Orthopaedic Research and Translational Science (CORTS), The Pennsylvania State University College of Medicine, Hershey, PA, United States
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University College of Medicine, Hershey, PA, United States
- Center for RNA Molecular Biology, Pennsylvania State University, University Park, State College, PA, United States
| |
Collapse
|
9
|
Kotsaris G, Qazi TH, Bucher CH, Zahid H, Pöhle-Kronawitter S, Ugorets V, Jarassier W, Börno S, Timmermann B, Giesecke-Thiel C, Economides AN, Le Grand F, Vallecillo-García P, Knaus P, Geissler S, Stricker S. Odd skipped-related 1 controls the pro-regenerative response of fibro-adipogenic progenitors. NPJ Regen Med 2023; 8:19. [PMID: 37019910 PMCID: PMC10076435 DOI: 10.1038/s41536-023-00291-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 03/17/2023] [Indexed: 04/07/2023] Open
Abstract
Skeletal muscle regeneration requires the coordinated interplay of diverse tissue-resident- and infiltrating cells. Fibro-adipogenic progenitors (FAPs) are an interstitial cell population that provides a beneficial microenvironment for muscle stem cells (MuSCs) during muscle regeneration. Here we show that the transcription factor Osr1 is essential for FAPs to communicate with MuSCs and infiltrating macrophages, thus coordinating muscle regeneration. Conditional inactivation of Osr1 impaired muscle regeneration with reduced myofiber growth and formation of excessive fibrotic tissue with reduced stiffness. Osr1-deficient FAPs acquired a fibrogenic identity with altered matrix secretion and cytokine expression resulting in impaired MuSC viability, expansion and differentiation. Immune cell profiling suggested a novel role for Osr1-FAPs in macrophage polarization. In vitro analysis suggested that increased TGFβ signaling and altered matrix deposition by Osr1-deficient FAPs actively suppressed regenerative myogenesis. In conclusion, we show that Osr1 is central to FAP function orchestrating key regenerative events such as inflammation, matrix secretion and myogenesis.
Collapse
Affiliation(s)
- Georgios Kotsaris
- Institute of Chemistry and Biochemistry, Musculoskeletal Development and Regeneration Group, Freie Universität Berlin, Thielallee 63, 14195, Berlin, Germany
- Berlin-Brandenburg School for Regenerative Therapies, Charité - Universitätsmedizin Berlin, 13353, Berlin, Germany
| | - Taimoor H Qazi
- Berlin Institute of Health at Charité - Universitätsmedizin Berlin, BIH Julius Wolff Institute, Augustenburger Platz 1, 13353, Berlin, Germany
- Department of Bioengineering, University of Pennsylvania, 19104, Philadelphia, USA
- Weldon School of Biomedical Engineering, Purdue University, 47907, West Lafayette, IN, USA
| | - Christian H Bucher
- Berlin Institute of Health at Charité - Universitätsmedizin Berlin, BIH Julius Wolff Institute, Augustenburger Platz 1, 13353, Berlin, Germany
- Berlin Institute of Health at Charité - Universitätsmedizin Berlin, BIH Center for Regenerative Therapies (BCRT), Charitéplatz 1, 10117, Berlin, Germany
| | - Hafsa Zahid
- Institute of Chemistry and Biochemistry, Musculoskeletal Development and Regeneration Group, Freie Universität Berlin, Thielallee 63, 14195, Berlin, Germany
- International Max Planck Research School for Biology and Computing IMPRS-BAC, Berlin, Germany
- Max Planck Institute for Molecular Genetics, Ihnestrasse 73, 14195, Berlin, Germany
| | - Sophie Pöhle-Kronawitter
- Institute of Chemistry and Biochemistry, Musculoskeletal Development and Regeneration Group, Freie Universität Berlin, Thielallee 63, 14195, Berlin, Germany
| | - Vladimir Ugorets
- Institute of Chemistry and Biochemistry, Cell Signaling Group, Freie Universität Berlin, Thielallee 63, 14195, Berlin, Germany
| | - William Jarassier
- Institut NeuroMyoGène, CNRS UMR 5261, Inserm U1315, Université Claude Bernard Lyon 1, 69008, Lyon, France
| | - Stefan Börno
- Max Planck Institute for Molecular Genetics, Ihnestrasse 73, 14195, Berlin, Germany
| | - Bernd Timmermann
- Max Planck Institute for Molecular Genetics, Ihnestrasse 73, 14195, Berlin, Germany
| | | | | | - Fabien Le Grand
- Institut NeuroMyoGène, CNRS UMR 5261, Inserm U1315, Université Claude Bernard Lyon 1, 69008, Lyon, France
| | - Pedro Vallecillo-García
- Institute of Chemistry and Biochemistry, Musculoskeletal Development and Regeneration Group, Freie Universität Berlin, Thielallee 63, 14195, Berlin, Germany
| | - Petra Knaus
- Berlin-Brandenburg School for Regenerative Therapies, Charité - Universitätsmedizin Berlin, 13353, Berlin, Germany
- Institute of Chemistry and Biochemistry, Cell Signaling Group, Freie Universität Berlin, Thielallee 63, 14195, Berlin, Germany
| | - Sven Geissler
- Berlin Institute of Health at Charité - Universitätsmedizin Berlin, BIH Julius Wolff Institute, Augustenburger Platz 1, 13353, Berlin, Germany
- Berlin Institute of Health at Charité - Universitätsmedizin Berlin, BIH Center for Regenerative Therapies (BCRT), Charitéplatz 1, 10117, Berlin, Germany
- Berlin Center for Advanced Therapies (BECAT), Charité Universitätsmedizin Berlin, Augustenburger Platz 1, Berlin, Germany
| | - Sigmar Stricker
- Institute of Chemistry and Biochemistry, Musculoskeletal Development and Regeneration Group, Freie Universität Berlin, Thielallee 63, 14195, Berlin, Germany.
- Berlin-Brandenburg School for Regenerative Therapies, Charité - Universitätsmedizin Berlin, 13353, Berlin, Germany.
| |
Collapse
|
10
|
Haeusner S, Jauković A, Kupczyk E, Herrmann M. Review: cellularity in bone marrow autografts for bone and fracture healing. Am J Physiol Cell Physiol 2023; 324:C517-C531. [PMID: 36622067 DOI: 10.1152/ajpcell.00482.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The use of autografts, as primary cell and tissue source, is the current gold standard approach to treat critical size bone defects and nonunion defects. The unique mixture of the autografts, containing bony compartments and bone marrow (BM), delivers promising results. Although BM mesenchymal stromal cells (BM-MSCs) still represent a major target for various healing approaches in current preclinical research and respective clinical trials, their occurrence in the human BM is typically low. In vitro expansion of this cell type is regulatory challenging as well as time and cost intensive. Compared with marginal percentages of resident BM-MSCs in BM, BM mononuclear cells (BM-MNCs) contained in BM aspirates, concentrates, and bone autografts represent a readily available abundant cell source, applicable within hours during surgical procedures without the need for time-consuming and regulatory challenging cell expansion. This benefit is one reason why autografting has become a clinical standard procedure. However, the exact anatomy and cellularity of BM-MNCs in humans, which is strongly correlated to their unique mode of action and wide application range remains to be elucidated. The aim of this review was to present an overview of the current knowledge on these specific cell types found in human BM, emphasize the contribution of BM-MNCs in bone healing, highlight donor site dependence, and discuss limitations in the current isolation and subsequent characterization procedures. Hereby, the most recent and relevant examples of human BM-MNC cell characterization, flow cytometric analyses, and findings are summarized, with a strong focus on bone therapy.
Collapse
Affiliation(s)
- S Haeusner
- IZKF Group Tissue Regeneration in Musculoskeletal Diseases, University Hospital of Wuerzburg, Wuerzburg, Germany.,Bernhard-Heine-Center for Locomotion Research, University of Wuerzburg, Wuerzburg, Germany
| | - A Jauković
- Group for Hematology and Stem Cells, Institute for Medical Research, University of Belgrade, Belgrade, Serbia
| | - E Kupczyk
- Department of Trauma, Hand, Plastic and Reconstructive Surgery, University Hospital of Wuerzburg, Wuerzburg, Germany
| | - M Herrmann
- IZKF Group Tissue Regeneration in Musculoskeletal Diseases, University Hospital of Wuerzburg, Wuerzburg, Germany.,Bernhard-Heine-Center for Locomotion Research, University of Wuerzburg, Wuerzburg, Germany
| |
Collapse
|