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Kano T, Minegish Y, Terada H, Takasu C, Kojima T, Oka Y, Kawabata S, Shimada N, Morishita Y, Murata K, Kanemura N. The infrapatellar fat pad contributes to spontaneous healing after complete anterior cruciate ligament injury. Exp Biol Med (Maywood) 2023; 248:1895-1904. [PMID: 38149772 PMCID: PMC10792419 DOI: 10.1177/15353702231215921] [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: 05/10/2023] [Accepted: 10/12/2023] [Indexed: 12/28/2023] Open
Abstract
Anterior cruciate ligament (ACL) injuries have a very low healing capacity but have recently been shown to heal spontaneously with conservative treatment. This study examined the mechanism of spontaneous ACL healing by focusing on the intra-articular tissues of the knee joint. Skeletally mature Wistar rats (n = 70) were randomly assigned to two groups: the controlled abnormal movement (CAM) and anterior cruciate ligament transection (ACLT) groups. The ACL was completely transected at the mid-portion in both groups. Only the CAM group underwent extra-articular braking to control for abnormal tibial translation. The animals were allowed full cage activity until sacrifice for histological, and molecular biology analyses. The results showed that the behavior of the stump after ACL injury differed between models 12 h after injury. The femoral stump in the ACLT group retreated posteriorly and upwardly. Macrophage polarity analysis revealed that the stump immune response in the CAM group was more activated than that in the ACLT group 6 h after injury. Microarray analysis of the ACL parenchyma and infrapatellar fat pads suggested the involvement of nuclear factor kappa B (NF-κB) signaling. Real-time polymerase chain reaction (PCR) analysis showed that NF-κB gene expression in the infrapatellar fat pad was significantly increased in the CAM group than in the ACLT group. However, there was no difference in the gene expression levels in the ACL parenchyma between models. In conclusion, the healing response of the ACL was activated within 12 h of injury, resulting in differences in the healing response between the models. It has been suggested that infrapatellar fat pads are involved in the healing process and that angiogenesis and antiapoptotic effects through NF-κB signaling may contribute to this mechanism.
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Affiliation(s)
- Takuma Kano
- Department of Health and Social Services, Graduate School of Saitama Prefectural University, Saitama 343-8540, Japan
- Soka Orthopedic Internal Medicine, Saitama 340-0016, Japan
- Yatsuka Orthopedic Internal Medicine, Saitama 340-0028, Japan
| | - Yuki Minegish
- Department of Health and Social Services, Graduate School of Saitama Prefectural University, Saitama 343-8540, Japan
- Department of Rehabilitation, Faculty of Health Sciences, Nihon Institute of Medical Science, Saitama 350-0435, Japan
| | - Hidenobu Terada
- Department of Health and Social Services, Graduate School of Saitama Prefectural University, Saitama 343-8540, Japan
- Yatsuka Orthopedic Internal Medicine, Saitama 340-0028, Japan
| | - Chiharu Takasu
- Department of Health and Social Services, Graduate School of Saitama Prefectural University, Saitama 343-8540, Japan
- Yatsuka Orthopedic Internal Medicine, Saitama 340-0028, Japan
| | - Takuma Kojima
- Department of Health and Social Services, Graduate School of Saitama Prefectural University, Saitama 343-8540, Japan
- Soka Orthopedic Internal Medicine, Saitama 340-0016, Japan
| | - Yuichiro Oka
- Faculty of Health Sciences, Hokkaido University, Sapporo 060-0812, Japan
| | - Sora Kawabata
- Department of Health and Social Services, Graduate School of Saitama Prefectural University, Saitama 343-8540, Japan
| | - Naoki Shimada
- Department of Health and Social Services, Graduate School of Saitama Prefectural University, Saitama 343-8540, Japan
| | | | - Kenji Murata
- Saitama Prefectural University, Saitama 343-8540, Japan
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Kano T, Kokubun T, Murata K, Oka Y, Ozone K, Arakawa K, Morishita Y, Takayanagi K, Kanemura N. Influence of the site of injury on the spontaneous healing response in a rat model of total rupture of the anterior cruciate ligament. Connect Tissue Res 2022; 63:138-150. [PMID: 33588658 DOI: 10.1080/03008207.2021.1889529] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
AIM The healing ability of the anterior cruciate ligament (ACL) injury is very poor; however, it has recently been shown to undergo self-healing with conservative treatments. In this study, we evaluated the influence of the site of injury on the healing process after complete transverse tear of ACL using a rat model. MATERIALS AND METHODS A total of 58 skeletally mature Wistar rats were randomly assigned to various ACL injury groups: controlled abnormal movement-mid-portion (CAM-MP), controlled abnormal movement-femoral side (CAM-FS), ACL transection-mid-portion (ACLT-MP), or ACL transection-femoral side (ACLT-FS) injury groups. The ACL was completely transected in the mid-portion in the ACLT-MP and CAM-MP groups, and on the femoral side in the ACLT-FS and CAM-FS groups. Both CAM groups underwent extra-articular braking to control for abnormal tibial translation. The animals were allowed full cage activity until sacrifice postoperatively for histological and biomechanical assessment. RESULTS Significant differences were found in the ratios of residual ligament lengths between the CAM-MP and CAM-FS groups, demonstrating the validity of each model. Spontaneous healing of the injured ACL was observed in the CAM-MP and CAM-FS groups but not in the ACLT-MP and ACLT-FS groups. The mechanical strength of the healing ACL did not differ between the CAM-MP and CAM-FS groups 8 weeks after injury; however, the former had better mechanical strength than the latter 12 weeks after the injury. CONCLUSION ACL injuries in the mid-portion and on the femoral side may be treated with conservative therapy for spontaneous healing.
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Affiliation(s)
- Takuma Kano
- Graduate Course of Health and Social Services, Graduate School of Saitama Prefectural University, Koshigaya, Japan.,Department of Rehabilitation, Soka Orthopedics Internal Medicine, Soka, Japan.,Department of Rehabilitation, Yatsuka Orthopedics Internal Medicine, Soka, Japan
| | - Takanori Kokubun
- Department of Physical Therapy, School of Health and Social Services, Saitama Prefectural University, Koshigaya, Japan
| | - Kenji Murata
- Department of Physical Therapy, School of Health and Social Services, Saitama Prefectural University, Koshigaya, Japan
| | - Yuichiro Oka
- Graduate Course of Health and Social Services, Graduate School of Saitama Prefectural University, Koshigaya, Japan
| | - Kaichi Ozone
- Graduate Course of Health and Social Services, Graduate School of Saitama Prefectural University, Koshigaya, Japan
| | - Kohei Arakawa
- Graduate Course of Health and Social Services, Graduate School of Saitama Prefectural University, Koshigaya, Japan
| | - Yuri Morishita
- Graduate Course of Health and Social Services, Graduate School of Saitama Prefectural University, Koshigaya, Japan
| | - Kiyomi Takayanagi
- Department of Physical Therapy, School of Health and Social Services, Saitama Prefectural University, Koshigaya, Japan
| | - Naohiko Kanemura
- Department of Physical Therapy, School of Health and Social Services, Saitama Prefectural University, Koshigaya, Japan
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Murray MM. Optimizing outcomes of ACL surgery-Is autograft reconstruction the only reasonable option? J Orthop Res 2021; 39:1843-1850. [PMID: 34191344 PMCID: PMC8387392 DOI: 10.1002/jor.25128] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 06/25/2021] [Indexed: 02/04/2023]
Abstract
Anterior cruciate ligament (ACL) injuries occur at a high frequency in the United States with approximately 400,000 ACL reconstructions being performed each year. While ACL reconstruction is our current gold standard of treatment, it does not restore joint motion, or prevent the premature development of posttraumatic osteoarthritis (PTOA) in many patients. Thus, new treatments for an ACL injury, which are less invasive and minimize patient morbidity, including cartilage damage, are highly desirable. We have used a tissue-engineered approach to stimulate ligament healing, to improve upon current treatment options. In this review, we describe and discuss our work moving a tissue engineering strategy from the concept to bench, preclinical, clinical trials and ultimately FDA 510(k) de Novo approval, providing clinicians and patients with a viable alternative to ACL reconstruction.
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Affiliation(s)
- Martha M. Murray
- Department of Orthopaedic Surgery, Division of Sports Medicine, Boston Children's Hospital Harvard Medical School Boston Massachusetts USA
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Youssefzadeh KA, Stein SM, Limpisvasti O. Anterior Cruciate Ligament Repair Using a Knotless Suture Implant. Arthrosc Tech 2020; 9:e623-e626. [PMID: 32489836 PMCID: PMC7253715 DOI: 10.1016/j.eats.2020.01.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 01/09/2020] [Indexed: 02/03/2023] Open
Abstract
Recent orthopedic literature has shown that primary repair for femoral-sided avulsion tears of the anterior cruciate ligament (ACL) can be successful. Primary ACL repair avoids invasive reconstruction techniques, graft-site morbidity, and the loss of native anatomy while producing excellent results in appropriately selected patients. Here we describe our patient selection parameters, ACL repair technique, and rehabilitation protocol.
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Affiliation(s)
| | | | - Orr Limpisvasti
- Kerlan-Jobe Orthopaedic Clinic, Los Angeles, California, U.S.A
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Murray MM, Fleming BC, Badger GJ, Freiberger C, Henderson R, Barnett S, Kiapour A, Ecklund K, Proffen B, Sant N, Kramer DE, Micheli LJ, Yen YM. Bridge-Enhanced Anterior Cruciate Ligament Repair Is Not Inferior to Autograft Anterior Cruciate Ligament Reconstruction at 2 Years: Results of a Prospective Randomized Clinical Trial. Am J Sports Med 2020; 48:1305-1315. [PMID: 32298131 PMCID: PMC7227128 DOI: 10.1177/0363546520913532] [Citation(s) in RCA: 114] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Preclinical studies suggest that for complete midsubstance anterior cruciate ligament (ACL) injuries, a suture repair of the ACL augmented with a protein implant placed in the gap between the torn ends (bridge-enhanced ACL repair [BEAR]) may be a viable alternative to ACL reconstruction (ACLR). HYPOTHESIS We hypothesized that patients treated with BEAR would have a noninferior patient-reported outcomes (International Knee Documentation Committee [IKDC] Subjective Score; prespecified noninferiority margin, -11.5 points) and instrumented anteroposterior (AP) knee laxity (prespecified noninferiority margin, +2-mm side-to-side difference) and superior muscle strength at 2 years after surgery when compared with patients who underwent ACLR with autograft. STUDY DESIGN Randomized controlled trial; Level of evidence, 1. METHODS One hundred patients (median age, 17 years; median preoperative Marx activity score, 16) with complete midsubstance ACL injuries were enrolled and underwent surgery within 45 days of injury. Patients were randomly assigned to receive either BEAR (n = 65) or autograft ACLR (n = 35 [33 with quadrupled semitendinosus-gracilis and 2 with bone-patellar tendon-bone]). Outcomes-including the IKDC Subjective Score, the side-to-side difference in instrumented AP knee laxity, and muscle strength-were assessed at 2 years by an independent examiner blinded to the procedure. Patients were unblinded after their 2-year visit. RESULTS In total, 96% of the patients returned for 2-year follow-up. Noninferiority criteria were met for both the IKDC Subjective Score (BEAR, 88.9 points; ACLR, 84.8 points; mean difference, 4.1 points [95% CI, -1.5 to 9.7]) and the side-to-side difference in AP knee laxity (BEAR, 1.61 mm; ACLR, 1.77 mm; mean difference, -0.15 mm [95% CI, -1.48 to 1.17]). The BEAR group had a significantly higher mean hamstring muscle strength index than the ACLR group at 2 years (98.2% vs 63.2%; P < .001). In addition, 14% of the BEAR group and 6% of the ACLR group had a reinjury that required a second ipsilateral ACL surgical procedure (P = .32). Furthermore, the 8 patients who converted from BEAR to ACLR in the study period and returned for the 2-year postoperative visit had similar primary outcomes to patients who had a single ipsilateral ACL procedure. CONCLUSION BEAR resulted in noninferior patient-reported outcomes and AP knee laxity and superior hamstring muscle strength when compared with autograft ACLR at 2-year follow-up in a young and active cohort. These promising results suggest that longer-term studies of this technique are justified. REGISTRATION NCT02664545 (ClinicalTrials.gov identifier).
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Affiliation(s)
- Martha M. Murray
- Martha M. Murray, MD, Division of Sports Medicine, Department of Orthopaedic Surgery, Boston Children’s Hospital, 300 Longwood Ave, Hunnewell 2, Boston, MA 02115, USA ()
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Perrone GS, Proffen BL, Kiapour AM, Sieker JT, Fleming BC, Murray MM. Bench-to-bedside: Bridge-enhanced anterior cruciate ligament repair. J Orthop Res 2017; 35:2606-2612. [PMID: 28608618 PMCID: PMC5729057 DOI: 10.1002/jor.23632] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2017] [Accepted: 06/05/2017] [Indexed: 02/04/2023]
Abstract
Anterior cruciate ligament (ACL) injuries are one of the most well-known orthopaedic injuries and are treated with one of the most common orthopaedic procedures performed in the United States. This surgical procedure, ACL reconstruction, is successful at restoring the gross stability of the knee. However, the outcomes of ACL reconstruction can be limited by short and long-term complications, including muscle weakness, graft rupture, and premature osteoarthritis. Thus, new methods of treating this injury are being explored. This review details the pathway of how a tissue engineering strategy can be used to improve the healing of the ACL in preclinical studies and then translated to patients in an FDA-approved clinical study. This review paper will outline the clinical importance of ACL injuries, history of primary repair, the pathology behind failure of the ACL to heal, pre-clinical studies, the FDA approval process for a high risk medical device, and the preliminary results from a first-in-human study. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2606-2612, 2017.
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Affiliation(s)
- Gabriel S Perrone
- Department of Orthopaedic Surgery, Sports Medicine Research Laboratory, Harvard Medical School/Boston Children's Hospital, Boston, Massachusetts
| | - Benedikt L Proffen
- Department of Orthopaedic Surgery, Sports Medicine Research Laboratory, Harvard Medical School/Boston Children's Hospital, Boston, Massachusetts
| | - Ata M Kiapour
- Department of Orthopaedic Surgery, Sports Medicine Research Laboratory, Harvard Medical School/Boston Children's Hospital, Boston, Massachusetts
| | - Jakob T Sieker
- Department of Orthopaedic Surgery, Sports Medicine Research Laboratory, Harvard Medical School/Boston Children's Hospital, Boston, Massachusetts
| | - Braden C Fleming
- Department of Orthopaedics, Bioengineering Labs, Warren Alpert Medical School of Brown University/Rhode Island Hospital, Providence, Rhode Island
| | - Martha M Murray
- Department of Orthopaedic Surgery, Sports Medicine Research Laboratory, Harvard Medical School/Boston Children's Hospital, Boston, Massachusetts
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Laver L, Carmont MR, McConkey MO, Palmanovich E, Yaacobi E, Mann G, Nyska M, Kots E, Mei-Dan O. Plasma rich in growth factors (PRGF) as a treatment for high ankle sprain in elite athletes: a randomized control trial. Knee Surg Sports Traumatol Arthrosc 2015; 23:3383-92. [PMID: 24938396 DOI: 10.1007/s00167-014-3119-x] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Accepted: 06/03/2014] [Indexed: 11/29/2022]
Abstract
PURPOSE Syndesmotic sprains are uncommon injuries that require prolonged recovery. The influence of ultrasound-guided injections of platelet-rich plasma (PRP) into the injured antero-inferior tibio-fibular ligaments (AITFL) in athletes on return to play (RTP) and dynamic stability was studied. METHODS Sixteen elite athletes with AITFL tears were randomized to a treatment group receiving injections of PRP or to a control group. All patients followed an identical rehabilitation protocol and RTP criteria. Patients were prospectively evaluated for clinical ability to return to full activity and residual pain. Dynamic ultrasound examinations were performed at initial examination and at 6 weeks post-injury to demonstrate re-stabilization of the syndesmosis joint and correlation with subjective outcome. RESULTS All patients presented with a tear to the AITFL with dynamic syndesmosis instability in dorsiflexion-external rotation, and larger neutral tibia-fibula distance on ultrasound. Early diagnosis and treatment lead to shorter RTP, with 40.8 (±8.9) and 59.6 (±12.0) days for the PRP and control groups, respectively (p = 0.006). Significantly less residual pain upon return to activity was found in the PRP group; five patients (62.5 %) in the control group returned to play with minor discomfort versus one patient in the treatment group (12.5 %). One patient in the control group had continuous pain and disability and subsequently underwent syndesmosis reconstruction. CONCLUSIONS Athletes suffering from high ankle sprains benefit from ultrasound-guided PRP injections with a shorter RTP, re-stabilization of the syndesmosis joint and less long-term residual pain. LEVEL OF EVIDENCE II.
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Affiliation(s)
- Lior Laver
- Department of Orthopaedic Surgery, Sports Medicine Unit, "Meir" Medical Center, The Sackler School of Medicine (Tel-Aviv University), Kfar-Saba, Israel. .,Division of Sports Medicine, Department of Orthopaedic Surgery, Duke University, Durham, NC, USA.
| | - Michael R Carmont
- Department of Trauma and Orthopaedic Surgery, Princess Royal Hospital, Telford, Shropshire, UK
| | - Mark O McConkey
- Pacific Orthopaedics and Sports Medicine, North Vancouver, BC, Canada
| | - Ezequiel Palmanovich
- Department of Orthopaedic Surgery, Sports Medicine Unit, "Meir" Medical Center, The Sackler School of Medicine (Tel-Aviv University), Kfar-Saba, Israel
| | - Eyal Yaacobi
- Department of Orthopaedic Surgery, Sports Medicine Unit, "Meir" Medical Center, The Sackler School of Medicine (Tel-Aviv University), Kfar-Saba, Israel
| | - Gideon Mann
- Department of Orthopaedic Surgery, Sports Medicine Unit, "Meir" Medical Center, The Sackler School of Medicine (Tel-Aviv University), Kfar-Saba, Israel.,Ribstein Center for Sport Medicine Sciences and Research, Wingate Institute, Netanya, Israel
| | - Meir Nyska
- Department of Orthopaedic Surgery, Sports Medicine Unit, "Meir" Medical Center, The Sackler School of Medicine (Tel-Aviv University), Kfar-Saba, Israel
| | - Eugene Kots
- Department of Radiology, Sports Medicine Unit, "Meir" Medical Center, Kfar-Saba, Israel
| | - Omer Mei-Dan
- Department of Sports Medicine, University of Colorado Hospitals, Boulder, CO, USA
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Micro-composite substrates for the study of cell-matrix mechanical interactions. J Mech Behav Biomed Mater 2014; 38:232-41. [DOI: 10.1016/j.jmbbm.2014.01.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2013] [Revised: 12/03/2013] [Accepted: 01/14/2014] [Indexed: 01/13/2023]
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Rodeo SA, Boden SD, Murray MM, Einhorn TA. 2011 AOA Symposium: Tissue Engineering and Tissue Regeneration: AOA critical issues. J Bone Joint Surg Am 2013; 95:e109. [PMID: 23925754 PMCID: PMC3748991 DOI: 10.2106/jbjs.k.01505] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- Scott A. Rodeo
- Tissue Engineering, Repair, and Regeneration Program, The Hospital for Special Surgery, 535 East 70th Street, New York, NY 10021. E-mail address:
| | - Scott D. Boden
- Emory Orthopaedic and Spine Center, 59 Executive Park South, Suite 3000, Atlanta, GA 30320. E-mail address:
| | - Martha M. Murray
- Department of Orthopaedic Surgery, Children’s Hospital of Boston, Hunnewell 2, 300 Longwood Avenue, Boston, MA 02115. E-mail address:
| | - Thomas A. Einhorn
- Department of Orthopaedic Surgery, Boston University Medical Center, 720 Harrison Avenue, Suite 808, Boston, MA 02118. E-mail address:
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Abstract
Osteoarthritis (OA), a prevalent chronic condition with a striking impact on quality of life, represents an enormous societal burden that increases greatly as populations age. Yet no approved pharmacological intervention, biologic therapy or procedure prevents the progressive destruction of the OA joint. Mesenchymal stem cells (MSCs)-multipotent precursors of connective tissue cells that can be isolated from many adult tissues, including those of the diarthrodial joint-have emerged as a potential therapy. Endogenous MSCs contribute to maintenance of healthy tissues by acting as reservoirs of repair cells or as immunomodulatory sentinels to reduce inflammation. The onset of degenerative changes in the joint is associated with aberrant activity or depletion of these cell reservoirs, leading to loss of chondrogenic potential and preponderance of a fibrogenic phenotype. Local delivery of ex vivo cultures of MSCs has produced promising outcomes in preclinical models of joint disease. Mechanistically, paracrine signalling by MSCs might be more important than differentiation in stimulating repair responses; thus, paracrine factors must be assessed as measures of MSC therapeutic potency, to replace traditional assays based on cell-surface markers and differentiation. Several early-stage clinical trials, initiated or underway in 2013, are testing the delivery of MSCs as an intra-articular injection into the knee, but optimal dose and vehicle are yet to be established.
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Magarian EM, Vavken P, Murray MM. Human anterior cruciate ligament fibroblasts from immature patients have a stronger in vitro response to platelet concentrates than those from mature individuals. Knee 2011; 18:247-51. [PMID: 20728363 PMCID: PMC2991424 DOI: 10.1016/j.knee.2010.05.015] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2010] [Revised: 05/19/2010] [Accepted: 05/22/2010] [Indexed: 02/02/2023]
Abstract
A number of recently published studies have established a substantial age dependence of the response of ACL fibroblasts to stimulation by platelet-rich plasma (PRP). Further in-depth research of this age dependence revealed negative effects on both histological and biomechanical results in a large animal model. However, while it has been postulated that this association could affect potential human applications negatively too it remains to be proven that the same effects occur in human cells. Thus it was the objective of this study to search for age dependence in human fibroblasts before further human experiments are done. Human fibroblasts were obtained from 10 immature and adolescent patients, based on a-priori power calculations, and cultured in a collagen-PRP composite. Three parameters that are pivotal for defect remodeling and wound healing-cell migration, cell proliferation, and scaffold contraction-were chosen as endpoints. Both migration and proliferation were significantly higher in immature cells, but no differences were seen in wound contraction. The former findings suggest that immature patients respond more favorably to treatment with PRP, which consequently might translate into better results in ACL tissue engineering.
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Affiliation(s)
- Elise M Magarian
- Department of Orthopaedic Surgery, Children's Hospital of Boston, Harvard Medical School, Boston, MA 02115, United States
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Wang Y, Tang Z, Xue R, Singh GK, Lv Y, Shi K, Cai K, Deng L, Yang L. TGF-β1 promoted MMP-2 mediated wound healing of anterior cruciate ligament fibroblasts through NF-κB. Connect Tissue Res 2011; 52:218-25. [PMID: 20932173 DOI: 10.3109/03008207.2010.516849] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The adult human anterior cruciate ligament (ACL) has poor functional healing response. Transforming growth factor (TGF)-β1 enhances the wound repair by stimulating matrix proteins deposition as well as the proliferation and migration of cells. However, the function of the TGF-β1-induced matrix metalloproteinases' (MMPs) activities in the wound healing process is poorly understood. In this study, exogenous MMP-2 is added to mimic the TGF-β1-induced MMP-2 expression. Role of NF-κB pathway is further examined. Our results show that TGF-β1 induces dramatic elevation of MMP-2 activities and the MMP-2/tissue inhibitors of metalloproteinases ratio. Furthermore, the exogenous MMP-2 significantly promoted in vitro wound healing abilities of ACL fibroblasts that are significantly blocked with the addition of its inhibitors. TGF-β1 also increases the proliferation of ACL fibroblasts whereas MMP-2 alone does not, indicating that MMP-2 activities are not involved in the proliferation. TGF-β1-induced MMP-2 activity is inhibited by Bay11-7082 and Bay11-7085 (NF-κB inhibitors). Our results demonstrate that increased TGF-β1 facilitates the ACL healing process by promoting the fibroblasts migration and proliferation. The migration process is mediated by MMP-2 and NF-κB pathway is involved in TGF-β1-mediated MMP-2 release.
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Affiliation(s)
- Yequan Wang
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University , Chongqing , PR China
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13
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Kim HM, Galatz LM, Das R, Havlioglu N, Rothermich SY, Thomopoulos S. The role of transforming growth factor beta isoforms in tendon-to-bone healing. Connect Tissue Res 2011; 52:87-98. [PMID: 20615095 DOI: 10.3109/03008207.2010.483026] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The purpose of this study was to examine the role of two of the three transforming growth factor beta (TGF-β) isoforms at the healing tendon-to-bone insertion. The supraspinatus tendons of 64 rats were transected at their bony insertions and repaired to the humeral head. One shoulder of each rat received an osmotic pump for sustained delivery of the following factors at the repair site: (1) TGF-β1 and neutralizing antibodies to TGF-β2 and 3 (TGF-β1 group), (2) TGF-β3 and neutralizing antibodies to TGF-β1 and 2 (TGF-β3 group), (3) neutralizing antibodies to TGF-β1, 2, and 3 (anti-TGF-β group), and (4) saline (saline group). The contralateral shoulders received saline to serve as paired controls. The repairs were evaluated at multiple time points postmortem using histology-based assays and biomechanical testing. Treated shoulders in the TGF-β1 group showed increased type III collagen production compared to the paired control shoulders, indicative of a scar-mediated response. There was a trend toward reduced mechanical properties in the TGF-β1 group, but these changes did not reach statistical significance. The anti-TGF-β group showed no difference in tissue volume, but significantly inferior mechanical properties, compared to the paired control shoulders. The TGF-β3 group did not show any differences compared to the paired control shoulders. Although TGF-β isoforms play important roles in tendon-to-bone development and healing, application of exogenous TGF-β isoforms and neutralizing antibodies to the subacromial space using osmotic pumps did not improve supraspinatus tendon-to-bone healing.
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Affiliation(s)
- H Mike Kim
- Department of Orthopaedic Surgery, Washington University, St. Louis, Missouri 63110, USA
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Steinert AF, Kunz M, Prager P, Barthel T, Jakob F, Nöth U, Murray MM, Evans CH, Porter RM. Mesenchymal stem cell characteristics of human anterior cruciate ligament outgrowth cells. Tissue Eng Part A 2011; 17:1375-88. [PMID: 21247268 DOI: 10.1089/ten.tea.2010.0413] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
When ruptured, the anterior cruciate ligament (ACL) of the human knee has limited regenerative potential. However, the goal of this report was to show that the cells that migrate out of the human ACL constitute a rich population of progenitor cells and we hypothesize that they display mesenchymal stem cell (MSC) characteristics when compared with adherent cells derived from bone marrow or collagenase digests from ACL. We show that ACL outgrowth cells are adherent, fibroblastic cells with a surface immunophenotype strongly positive for cluster of differentiation (CD)29, CD44, CD49c, CD73, CD90, CD97, CD105, CD146, and CD166, weakly positive for CD106 and CD14, but negative for CD11c, CD31, CD34, CD40, CD45, CD53, CD74, CD133, CD144, and CD163. Staining for STRO-1 was seen by immunohistochemistry but not flow cytometry. Under suitable culture conditions, the ACL outgrowth-derived MSCs differentiated into chondrocytes, osteoblasts, and adipocytes and showed capacity to self-renew in an in vitro assay of ligamentogenesis. MSCs derived from collagenase digests of ACL tissue and human bone marrow were analyzed in parallel and displayed similar, but not identical, properties. In situ staining of the ACL suggests that the MSCs reside both aligned with the collagenous matrix of the ligament and adjacent to small blood vessels. We conclude that the cells that emigrate from damaged ACLs are MSCs and that they have the potential to provide the basis for a superior, biological repair of this ligament.
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Affiliation(s)
- Andre F Steinert
- Department of Orthopaedic Surgery, König-Ludwig-Haus, Orthopaedic Center for Musculoskeletal Research, Julius-Maximilians-University, Würzburg, Germany.
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Ponsot E, Langberg H, Krogsgaard MR, Kjaer M, Kadi F. Telomere length of anterior crucial ligament after rupture: similar telomere length in injured and noninjured ACL portions. J Orthop Res 2011; 29:79-83. [PMID: 20629093 DOI: 10.1002/jor.21201] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The regeneration of ligaments following injury is a slow process compared to the healing of many other tissues and the underlying mechanisms remain unknown. The purpose of the study was to evaluate the proliferative potential of ligaments by assessing telomere length within three distinct parts of human anterior cruciate ligament (ACL) obtained during ACL reconstruction: the macroscopically injured proximal part and macroscopically noninjured mid- and distal portions in eight subjects (age 28 ± 8 years). The mean telomere length in ACL was within normal range of values usually reported for other tissues indicating that the endogenous machinery responsible for the proliferative potential of ligament is not implicated in its poor healing capacity. The three ACL parts showed similar mean TRF lengths (distal part: 11.5 ± 0.8 kbp, mid-portion: 11.8 ± 1.2 kbp, proximal part: 11.9 ± 1.6 kbp) and there was no relationship between mean telomere length in ACL and the healing duration after rupture. This implies that despite the occurrence of ligament repair including a phase of intense cell proliferation the proliferative potential of ruptured ACL is not impaired. This knowledge is important for scientists and clinicians aiming to understand the mechanisms behind the low healing capacity of ligament.
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Affiliation(s)
- Elodie Ponsot
- School of Health and Medical Sciences, Örebro University, Örebro 70182, Sweden
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Magarian EM, Fleming BC, Harrison SL, Mastrangelo AN, Badger GJ, Murray MM. Delay of 2 or 6 weeks adversely affects the functional outcome of augmented primary repair of the porcine anterior cruciate ligament. Am J Sports Med 2010; 38:2528-34. [PMID: 20855556 PMCID: PMC2996471 DOI: 10.1177/0363546510377416] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Enhanced primary anterior cruciate ligament repair, in which suture repair is performed in conjunction with a collagen-platelet composite to stimulate healing, is a potential new treatment option for anterior cruciate ligament injuries. Previous studies have evaluated this approach at the time of anterior cruciate ligament disruption. HYPOTHESIS Delaying surgery by 2 or 6 weeks would have a significant effect on the functional outcome of the repair. STUDY DESIGN Controlled laboratory study. METHODS Sixteen female Yorkshire pigs underwent staged, bilateral surgical anterior cruciate ligament transections. Anterior cruciate ligament transection was initially performed on 1 knee and the knee closed. Two or 6 weeks later, enhanced primary repair was performed in that knee while the contralateral knee had an anterior cruciate ligament transection and immediate repair. Biomechanical parameters were measured after 15 weeks in vivo to determine the effect of delay time relative to immediate repair on the healing response. RESULTS Yield load of the repairs at 15 weeks was decreased by 40% and 60% in the groups where repair was delayed for 2 and 6 weeks, respectively (P = .01). Maximum load showed similar results (55% and 60% decrease in the 2- and 6-week delay groups, respectively; P = .011). Linear stiffness also was adversely affected by delay (50% decrease compared with immediate repair after either a 2- or 6-week delay, P = .011). Anterior-posterior laxity after 15 weeks of healing was 40% higher in knees repaired after a 2-week delay and 10% higher in those repaired after a 6-week delay (P = .012) when tested at 30° of flexion, but was not significantly affected by delay when tested at 60° or 90° (P = .21). CONCLUSION A delay between anterior cruciate ligament injury and enhanced primary repair has a significant negative effect on the functional performance of the repair. CLINICAL RELEVANCE As future investigations assess new techniques of anterior cruciate ligament repair, the timing of the repair should be considered in the design and the interpretation of experimental studies.
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Affiliation(s)
- Elise M. Magarian
- Department of Orthopaedic Surgery, Children's Hospital of Boston, Harvard Medical School, Boston, MA 02115
| | | | - Sophia L. Harrison
- Department of Orthopaedic Surgery, Children's Hospital of Boston, Harvard Medical School, Boston, MA 02115
| | - Ashley N. Mastrangelo
- Department of Orthopaedic Surgery, Children's Hospital of Boston, Harvard Medical School, Boston, MA 02115
| | - Gary J. Badger
- Department of Biostatistics, University of Vermont, Burlington, VT
| | - Martha M. Murray
- Department of Orthopaedic Surgery, Children's Hospital of Boston, Harvard Medical School, Boston, MA 02115
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Vavken P, Murray MM. Translational studies in anterior cruciate ligament repair. TISSUE ENGINEERING PART B-REVIEWS 2010; 16:5-11. [PMID: 20143926 DOI: 10.1089/ten.teb.2009.0147] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Translational research, which can be explained as the principle of combining advances in both basic research and clinical understanding in a bedside-to-bench-to-bedside approach, has become one of the central themes of present-day medical research. One orthopedic problem that has strongly benefited from such an approach is tissue-engineering-enhanced primary repair of the anterior cruciate ligament. Recent years have shown a clearer definition of the clinical problem and established an underlying mechanistic cause of the incapacity of the anterior cruciate ligament to heal-the premature loss of provisional scaffold in the wound site. These clinical findings were then translated into a research objective, namely, to replace the missing scaffold with a biomaterial with appropriate structural and bio-stimulatory characteristics. Subsequently, a tissue-engineering-based treatment using a collagen-platelet composite was developed and tested in vitro. After proofing the efficacy of this new treatment in the laboratory, it was translated into a potential clinical application, which showed highly successful results in structural integrity and biomechanical capacity in large animal testing. This approach of defining the scientific mechanism underlying a clinical observation and then using that information to design new therapies is but one example of how translational research in tissue engineering can help define and develop new treatments for challenging problems faced by patients.
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Affiliation(s)
- Patrick Vavken
- Sports Medicine Research Laboratory, Department of Orthopedic Surgery, Children's Hospital Boston, Harvard Medical School, Boston, Massachusetts 02115, USA
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Ligamentization of tendon grafts treated with an endogenous preparation rich in growth factors: gross morphology and histology. Arthroscopy 2010; 26:470-80. [PMID: 20362825 DOI: 10.1016/j.arthro.2009.08.019] [Citation(s) in RCA: 155] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2009] [Revised: 05/25/2009] [Accepted: 08/29/2009] [Indexed: 02/02/2023]
Abstract
PURPOSE To investigate whether the application of a particular platelet-rich plasma preparation rich in growth factors (PRGF) during anterior cruciate ligament (ACL) surgery gives a potential advantage for better tendon graft ligamentization. METHODS This study included 37 volunteers who underwent either conventional (control group, n = 15) or PRGF-assisted (n = 22) ACL reconstruction with an autogenous hamstring and required second-look arthroscopy to remove hardware or loose bodies, treat meniscal tears or plica syndrome, or resect cyclops lesions at 6 to 24 months after ACL surgery. The gross morphologies of the grafts were evaluated on second-look arthroscopy by use of the full arthroscopic score (0 to 4 points) to evaluate graft thickness and apparent tension (0 to 2 points) plus synovial coverage (0 to 2 points). At the same time, biopsy specimens were harvested uniformly from the grafted tendons. In these specimens the histologic transformation of the tendon graft to ACL-like tissue was evaluated by use of the Ligament Tissue Maturity Index, and a score to assess the progression of new connective tissue enveloping the graft was created by use of 3 criteria previously used to characterize changes during ligament healing: cellularity, vascularity, and collagen properties. RESULTS The overall arthroscopic evaluation of PRGF-treated grafts showed an excellent rating in 57.1% of the knees (score of 4) and a fair rating in 42.9% (score of 2 or 3). In contrast, evaluation of untreated grafts showed an excellent rating in 33.3% of the knees, a fair rating in 46.7%, and a poor rating in 20% (score of 0 or 1). Overall, arthroscopic evaluations were not statistically different between PRGF and control groups (P = .051). PRGF treatment influenced the histologic characteristics of the tendon graft, resulting in tissue that was more mature than in controls (P = .024). Histologically evident newly formed connective tissue enveloping the graft was present in 77.3% of PRGF-treated grafts and 40% of controls. The appearance of the connective tissue envelope changed with increasing time from surgery. On the basis of the histologic findings, we suggest that the remodeling of PRGF-treated grafts involves the formation of synovial-like tissue enveloping the graft. This tissue is eventually integrated in the remodeled tendon graft, conferring a similar appearance to the normal ACL. CONCLUSIONS The use of PRGF influenced the histologic characteristics of tendon grafts, resulting in more remodeling compared with untreated grafts. We have shown temporal histologic changes during the 6- to 24-month postoperative period of graft maturation, with newly formed connective tissue enveloping most grafts treated with PRGF. LEVEL OF EVIDENCE Level III, case-control study.
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19
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The Future: Optimizing the Healing Environment in Anterior Cruciate Ligament Reconstruction. Sports Med Arthrosc Rev 2010; 18:48-53. [DOI: 10.1097/jsa.0b013e3181c0ccd5] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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21
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Stalling SS, Nicoll SB. Fetal ACL fibroblasts exhibit enhanced cellular properties compared with adults. Clin Orthop Relat Res 2008; 466:3130-7. [PMID: 18648900 PMCID: PMC2628219 DOI: 10.1007/s11999-008-0391-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2007] [Accepted: 06/30/2008] [Indexed: 01/31/2023]
Abstract
Fetal tendons and skin heal regeneratively without scar formation. Cells isolated from these fetal tissues exhibit enhanced cellular migration and collagen production in comparison to cells from adult tissue. We determined whether fetal and adult fibroblasts isolated from the anterior cruciate ligament (ACL), a tissue that does not heal regeneratively, exhibit differences in cell migration rates and collagen elaboration. An in vitro migration assay showed fetal ACL fibroblasts migrated twice as fast as adult ACL fibroblasts at a rate of 38.90 +/- 7.69 microm per hour compared with 18.88 +/- 4.18 microm per hour, respectively. Quantification of Type I collagen elaboration by enzyme-linked immunosorbent assay showed fetal ACL fibroblasts produced four times the amount of Type I collagen compared with adult ACL fibroblasts after 7 days in culture. We observed no differences in Type III collagen with time for adult or fetal ACL fibroblasts. Our findings indicate fetal ACL fibroblasts are intrinsically different from adult ACL fibroblasts, suggesting the healing potential of the ACL may be age-dependent.
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Affiliation(s)
- Simone S. Stalling
- Department of Bioengineering, University of Pennsylvania, 240 Skirkanich Hall, 210 South 33rd Street, Philadelphia, PA 19104 USA
| | - Steven B. Nicoll
- Department of Bioengineering, University of Pennsylvania, 240 Skirkanich Hall, 210 South 33rd Street, Philadelphia, PA 19104 USA ,Department of Orthopaedic Surgery, University of Pennsylvania, Philadelphia, PA USA
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Hofstaetter JG, Saad FA, Sunk IG, Bobacz K, Friehs I, Glimcher MJ. Age-dependent expression of VEGF isoforms and receptors in the rabbit anterior cruciate ligament. Biochim Biophys Acta Gen Subj 2007; 1770:997-1002. [PMID: 17459591 DOI: 10.1016/j.bbagen.2007.02.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2006] [Revised: 01/02/2007] [Accepted: 02/20/2007] [Indexed: 01/03/2023]
Abstract
Vascular endothelial growth factor (VEGF) gene gives rise to several distinct isoforms of VEGF. Those isoforms differ in biochemical and biological properties, and it has been reported that their expression patterns are tissue and age specific as well. We investigated the expression levels of VEGF isoforms (VEGF121, VEGF165, VEGF183, VEGF189) and its receptors (VEGFR-1, flt-1 and VEGFR-2, flk-1/KDR) in the anterior cruciate ligament (ACL) of 2- to 3-week-, 2-month-, and 18-month-old New Zealand White rabbits using Sybr green Real-Time RT-PCR. VEGF isoforms and both receptors were expressed in the ACL at all investigated ages. VEGF121 was found to be the most abundant isoform at the ages under investigation, followed by VEGF165, VEGF189 and VEGF183. All isoforms showed decreased expression levels with age, however the larger membrane bound isoforms, VEGF183 and VEGF189, showed the most striking age-associated decrease in expression level. VEGFR-1 expression levels increased with age, while the expression level of VEGFR-2 expression was highest at 2-3 weeks and was significantly lower at 2 and 18 months of age. Distinct age-associated differences in the expression level of VEGF isoforms as well as their receptors suggest differential physiological functions during development, maturation and ageing of the ACL.
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Affiliation(s)
- Jochen G Hofstaetter
- Laboratory for the Study of Skeletal Disorders and Rehabilitation, Department of Orthopaedic Surgery, Harvard Medical School, The Children's Hospital Boston, Boston, MA 02115, USA.
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Murray MM, Spindler KP, Abreu E, Muller JA, Nedder A, Kelly M, Frino J, Zurakowski D, Valenza M, Snyder BD, Connolly SA. Collagen-platelet rich plasma hydrogel enhances primary repair of the porcine anterior cruciate ligament. J Orthop Res 2007; 25:81-91. [PMID: 17031861 DOI: 10.1002/jor.20282] [Citation(s) in RCA: 215] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The anterior cruciate ligament (ACL) fails to heal after suture repair. One hypothesis for this failure is the premature loss of the fibrin clot, or provisional scaffolding, between the two ligament ends in the joint environment. To test this hypothesis, a substitute provisional scaffold of collagen-platelet rich plasma (PRP) hydrogel was used to fill the ACL wound site at the time of suture repair and the structural properties of the healing ACLs evaluated 4 weeks after surgery. Bilateral ACL transections were performed in five 30-kg Yorkshire pigs and treated with suture repair. In each animal, one of the repairs was augmented with placement of a collagen-PRP hydrogel at the ACL transection site, while the contralateral knee had suture repair alone. In addition, six control knees with intact ACLs from three additional animals were used as a control group. No postoperative immobilization was used. After 4 weeks the animals underwent in vivo magnetic resonance imaging to assess the size of the healing ACL, followed by biomechanical testing to determine tensile properties. The supplementation of suture repair with a collagen-PRP hydrogel resulted in significant improvements in load at yield, maximum load, and linear stiffness at 4 weeks. We conclude that use of a stabilized provisional scaffold, such as a collagen-PRP hydrogel, to supplement primary repair of the ACL can result in improved biomechanical properties at an early time point. Further studies to determine the long-term effect of primary repair enhancement are needed.
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Affiliation(s)
- Martha M Murray
- Department of Orthopaedic Surgery, Children's Hospital Boston, 300 Longwood Avenue, Harvard Medical School, Boston, Massachusetts 02115, USA.
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Puk CK, Miller DJ, Gamradt S, Wu BM, McAllister DR. The effects of short-term stimulation on fibroblast spreading in an in vitro 3D system. J Biomed Mater Res A 2006; 76:665-73. [PMID: 16294325 DOI: 10.1002/jbm.a.30581] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Although the short-term effects of mechanical and biochemical stimulation on cell protein and DNA production have recently begun to be evaluated using 3D models, the effects that such stimulation have on cell morphology and adaptation remains unclear. Using a custom-built bioreactor, we were able to create a systematic model to examine the short-term effects of stimulation on cell morphology in a 3D model, specifically by evaluating cell spreading as the short-term indicator of cell adaptation. Fibroblasts were seeded on a porous poly(L-lactic acid) scaffold and cultured in a computerized bioreactor for 24 h under various uniaxial strains (0, 0.6, 3, 6%) and frequencies (0.0125, 0.125 Hz). Also, the effects of transforming growth factor (TGF-beta1) (1, 10, 100 ng/mL) were examined on static, nonstimulated cells-scaffold constructs after 24 h. Fibroblasts that had been subjected to mechanical stretching were found to exhibit significantly more spreading than the static control group. Conversely, TGF-beta1 between 1 and 100 ng/mL did not produce any significant difference in fibroblast spreading from the control groups after 24 h. Collectively, the findings suggest that cell morphology and adaptation may be affected by short-term mechanical stimulation, as seen by increased cell spreading by the fibroblasts under these experimental conditions.
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Affiliation(s)
- C K Puk
- Department of Bioengineering, Henry Samueli School of Engineering and Applied Science, University of California, Los Angeles, USA
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Murray MM, Forsythe B, Chen F, Lee SJ, Yoo JJ, Atala A, Steinert A. The effect of thrombin on ACL fibroblast interactions with collagen hydrogels. J Orthop Res 2006; 24:508-15. [PMID: 16453341 DOI: 10.1002/jor.20054] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Premature loss of provisional scaffold formation has been identified as one of the factors responsible for poor healing of intraarticular tissues. To address this deficiency, substitute provisional scaffolds are being developed. The function of these scaffolds can be enhanced by the addition of specific extracellular matrix proteins. In this study, it was hypothesized that the addition of thrombin to a provisional scaffold material would result in increases in cell proliferation, collagen production, and cell migration within the scaffold. These three parameters are thought to be critical components of wound healing. Gels containing fibrin and collagen supplemented with either 0, 10.5, 21, or 42 U/mL of thrombin were placed in contact with explants of tissue from the anterior cruciate ligament. The addition of thrombin stimulated cell migration at low concentrations and impaired migration at higher concentrations, and had no significant effect on cell proliferation or collagen production. The use of all concentrations of thrombin resulted in mechanically weaker gels. Thus, the use of thrombin to optimize a collagen-platelet rich plasma (PRP) provisional scaffold must be done with caution, and use of high concentrations of thrombin (>42 IU/mL) should be avoided specifically in situations where gel strength or cell ingrowth is important. Use of low concentrations of thrombin (10.5 IU/mL) may be beneficial in applications where a faster set time and enhanced cell migration are desirable and the gel mechanical strength is of secondary importance.
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Affiliation(s)
- M M Murray
- Department of Orthopaedic Surgery, Children's Hospital of Boston, 300 Longwood Avenue, Boston, Massachusetts 02115, USA.
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Bramono DS, Richmond JC, Weitzel PP, Chernoff H, Martin I, Volloch V, Jakuba CM, Diaz F, Gandhi JS, Kaplan DL, Altman GH. Characterization of transcript levels for matrix molecules and proteases in ruptured human anterior cruciate ligaments. Connect Tissue Res 2005; 46:53-65. [PMID: 16019414 DOI: 10.1080/03008200590935556] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
An improved understanding of cellular responses during normal anterior cruciate ligament (ACL) function or repair is essential for clinical assessments, understanding ligament biology, and the implementation of tissue engineering strategies. The present study utilized quantitative real-time RT-PCR combined with univariate and multivariate statistical analyses to establish a quantitative database of marker transcript expression that can provide a "blueprint" of ACL wound healing. Selected markers (collagen types I and III, biglycan, decorin, MMP-1, MMP-2, MMP-9, and TIMP-1) were assessed from 33 torn ACLs harvested during reconstructive surgery. Trends were observed between postinjury period and marker expressions. Significant correlations between marker expression existed and were most prominent between collagen types I and III. Canonical correlation analysis established a relationship between patient demographics and a combination of all marker expressions. The currently observed trends and correlations may assist in identifying appropriate tissue samples and provide a baseline information of marker expression level that can support in vitro optimization of environmental cues for ligament tissue engineering application.
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Affiliation(s)
- Diah S Bramono
- Department of Biomedical Engineering, Tufts University, School of Engineering, Medford, Massachusetts 02155, USA
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Abstract
We review progress in the field of orthopaedic gene therapy since the concept of using gene transfer to address orthopaedic problems was initiated approximately 15 years ago. The original target, arthritis, has been the subject of two successful Phase I clinical trials, and additional human studies are pending in rheumatoid arthritis and osteoarthritis. The repair of damaged musculoskeletal tissues also has proved to be a fruitful area of research, and impressive enhancement of bone healing has been achieved in preclinical models. Rapid progress also is being made in the use of gene transfer to improve cartilage repair, ligament healing, and restoration of various additional tissues, including tendon and meniscus. Other applications include intervertebral disc degeneration, aseptic loosening, osteoporosis, genetic diseases, and orthopaedic tumors. Of these various orthopaedic targets of gene therapy, tissue repair is likely to make the earliest clinical impact because it can be achieved with existing technology. Tissue repair may become one of the earliest clinical successes for gene therapy as a whole. Orthopaedics promises to be a leading discipline for the use of human gene therapy.
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Affiliation(s)
- Christopher H Evans
- Center for Molecular Orthopaedics, Harvard Medical School, 221 Longwood Avenue, BL1-152, Boston, MA 02025, USA.
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