Equine allogeneic chondrogenic induced mesenchymal stem cells: A GCP target animal safety and biodistribution study

Allogeneic chondrogenic-induced mesenchymal stem cells for the treatment of tarsometatarsal lameness in horses

OBJECTIVE

To assess the efficacy of commercial intra-articular blood-derived allogeneic-induced mesenchymal stem cells (CIMSCs) to treat tarsometatarsal lameness in horses.

STUDY DESIGN

This was a retrospective cohort study.

ANIMALS

Records from 167 adult light breed horses with bilateral tarsometatarsal lameness.

METHODS

Horses with tarsometatarsal lameness were retrospectively selected from medical records. Diagnosis followed subjective graded lameness assessment before and after intra-articular analgesia, with graded radiographic tarsal examination. Horses were excluded if they were diagnosed or treated for any other concurrent lameness conditions during the study. Time to last follow-up and time of recurrence of lameness was recorded at veterinary re-assessment.

RESULTS

A total of 67 horses were recruited to the CIMSC-treated group and 100 to the corticosteroid (CS)-treated group. Median age was 9 years, with no difference in signalment, use or radiographic grade between groups. First re-examination was 38 days (95% CI: 38-49), with no difference between groups, CIMSC 42 (35-45), control 34 (25-42). Median follow-up was 438 days for CIMSC, 546 for controls. Symptoms of lameness recurred in 86/100 controls compared to 17/67 (25%) CIMSC. Median time to lameness recurring in CIMSC was 336 days (95% CI: 239-400), control 90 days (95% CI: 80-108), p < .0001. Cox proportional hazard ratio for treatment was 8.35, 95% CI: 4.67 to 14.92, p < .0001.

CONCLUSIONS

Lameness was abolished in all treated horses. It recurred significantly less often, and later, in CIMSC-treated horses.

CLINICAL SIGNIFICANCE

Intra-articular CIMSC treatment results in prolonged soundness in horses with tarsometatarsal lameness.

Systematic review and meta-analysis of positive long-term effects after intra-articular administration of orthobiologic therapeutics in horses with naturally occurring osteoarthritis

Equine veterinarians face challenges in treating horses with osteoarthritic joint pain in routine veterinary practice. All common treatment options aim to reduce the clinical consequences of osteoarthritis (OA) characterized by persistent synovitis and progressive degradation of articular cartilage. A range of joint-associated cell types and extracellular matrices are involved in the not yet entirely understood chronic inflammatory process. Regeneration of articular tissues to re-establish joint hemostasis is the future perspective when fundamental healing of OA is the long-term goal. The use of intra-articular applied biologic therapeutics derived from blood or mesenchymal stroma cell (MSC) sources is nowadays a well-accepted treatment option. Although this group of therapeutics is not totally consistent due to the lack of clear definitions and compositions, they all share a potential regenerative effect on articular tissues as described in in vivo and in vitro studies. However, the current stage of science in regenerative medicine needs to be supported by clinical reports as in fact, in vitro studies as well as studies using induced OA models still represent a fragment of the complex pathomechanism of naturally occurring OA. This systemic review aims to determine the long-term effect of orthobiologic therapeutics in horses suffering naturally occurring OA. Thereby, a meta-analysis of randomized controlled trials (RCTs) is conducted to describe the efficiency and safety of intra-articular applied orthobiologics in terms of lameness reduction in the long-term. Using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) guidelines, thirteen studies met the inclusion criteria for the systemic review. Four of those studies have further been evaluated by the meta-analysis comparing the long-term effect in lameness reduction. Each study was examined for risk of bias. For data evaluation, a random-effects model was used, describing the overall outcome in a forest plot. The I² statistic was used to assess heterogeneity. Results indicate, that orthobiologic therapies represent an effective long-term and safe OA treatment option. Due to the inhomogeneity of included studies, no statements are provided addressing specific orthobiologic therapies, affected joints, OA stage and horse's intended use. Future clinical trials should follow standardized study designs to provide comparable data.

The combination of BMP12 and KY02111 enhances tendon differentiation in bone marrow-derived equine mesenchymal stromal cells (BM-eMSCs)

The Wingless and Int-1 (WNT) and bone morphogenic protein/growth differentiation factor (BMP/GDF) signalling pathways contribute significantly to the development of the musculoskeletal system. The mechanism by which they contribute is as follows: BMP/GDF signalling usually promotes tendon differentiation, whereas WNT signalling inhibits it. We hypothesised that inhibiting WNT and subsequently stimulating BMP signalling may enhance the tenogenic differentiation of stem cells. The objective of this study was to determine whether a combination of WNT inhibitor (KY02111) and BMP12/GDF7 protein could enhance the differentiation of bone marrow-derived equine mesenchymal stromal cells (BM-eMSCs) into tenocytes. Cells were cultured in five treatments: control, BMP12, and three different combinations of BMP12 and KY02111. The results indicated that a 1-day treatment with KY02111 followed by a 13-day treatment with BMP12 resulted in the highest tenogenic differentiation score in this experiment. The effect of KY02111 is dependent on the incubation time, with 1 day being better than 3 or 5 days. This combination increased tenogenic gene marker expression, including SCX, TNMD, DCN, and TNC, as well as COL1 protein expression. In conclusion, we propose that a combination of BMP12 and KY02111 can enhance the in vitro tenogenic differentiation of BM-eMSCs more than BMP12 alone. The findings of this study might be useful for improving tendon differentiation protocols for stem cell transplantation and application to tendon regeneration.

Cellular and Humoral Immunogenicity Investigation of Single and Repeated Allogeneic Tenogenic Primed Mesenchymal Stem Cell Treatments in Horses Suffering From Tendon Injuries

The use of mesenchymal stem cells (MSCs) for the treatment of equine tendon disease is widely investigated because of their regenerative and immunomodulatory potential. However, questions have been raised concerning the immunogenic properties of allogeneic MSCs. Therefore, two studies were conducted to assess the safety of equine allogeneic peripheral blood-derived tenogenic primed MSCs (tpMSCs). The objective was to evaluate if a single and repeated tpMSC administration induced a cellular and humoral immune response in horses suffering from tendon injuries. Horses enrolled in the first study (n = 8) had a surgically induced superficial digital flexor tendon core lesion and were treated intralesionally with tpMSCs. Before and after treatment the cellular immunogenicity was assessed by modified mixed lymphocyte reactions. The humoral immune response was investigated using a crossmatch assay. Presence of anti-bovine serum albumin (BSA) antibodies was detected via ELISA. Horses enrolled in the second study (n = 6) suffered from a naturally occurring tendon injury and were treated twice with tpMSCs. Blood was collected after the second treatment for the same immunological assays. No cellular immune response was found in any of the horses. One out of eight horses in the first study and none of the horses in the second study had anti-tpMSC antibodies. This particular horse had an equine sarcoid and further investigation revealed presence of antibodies against sarcoid cells and epithelial-like stem cells before treatment, which increased after treatment. Additionally, formation of antibodies against BSA was observed. These findings might indicate a non-specific immune response generated after treatment. Serum from the other horses revealed no such antibody formation. These two studies showed that the administration of tpMSCs did not induce a cellular or humoral immune response following an intralesional single or repeated (two consecutive) allogeneic tpMSC treatment in horses with tendon injury, except for one horse. Therefore, a larger field study should confirm these findings and support the safe use of tpMSCs as a therapeutic for horses suffering from tendon injuries.

Repeated intra-articular administration of equine allogeneic peripheral blood-derived mesenchymal stem cells does not induce a cellular and humoral immune response in horses

OBJECTIVE

The use of mesenchymal stem cells (MSCs) for the treatment of equine joint disease is widely investigated because of their regenerative and immunomodulatory potential. Allogeneic MSCs provide a promising alternative to autologous MSCs, since the former are immediately available and enable a thorough donor screening. However, questions have been raised concerning the immunogenic potential of allogeneic MSCs, especially after repeated administration.

METHODS

Current retrospective study assessed the cellular and humoral immunogenicity of ten jumping and dressage horses with naturally occurring degenerative joint disease which were treated 3 times intra-articularly with a 1 mL stem cell suspension containing 1.4-2.5 million chondrogenic induced equine allogeneic peripheral blood-derived MSCs (ciMSCs) combined with 1 mL equine allogeneic plasma. Stem cells from 2 donor horses were used. Horses were clinically evaluated for joint effusion, presence of pain to palpation and skin surface temperature at the local injection site, joint range of motion, occurrence of adverse events and the presence of ectopic tissue. The cellular immune response was analyzed using a modified mixed lymphocyte reaction and the humoral immune response was investigated using a flow cytometric crossmatch assay by which the presence of alloantibodies against the ciMSCs was evaluated. Presence of anti-bovine serum albumin antibodies was detected via ELISA.

RESULTS

Clinical evaluation of the horses revealed no serious adverse effects or suspected adverse drug reactions and no ectopic tissue formation at the local injection site or in other areas of the body. Generally, repeated administration led to a decrease of horses with joint effusion of the affected joint. Pain to palpation, skin surface temperature and joint range of motion did not increase or even decreased after treatment administration. Allogeneic ciMSCs did not induce a cellular immune response and no alloantibodies were detected in the recipients' serum, regardless the presence of BSA antibodies in 70 % of the horses.

CONCLUSION

Repeated intra-articular injections with allogeneic equine ciMSCs did not elicit clinically relevant adverse events. Furthermore, current study indicates the absence of a cellular or a humoral immune response following repeated intra-articular injections.

[Cell-based therapeutic strategies for osteoarthritis in equine patients - Basic knowledge for clinical practitioners]

Cell-based therapies for the treatment of osteoarthritis in equine patients experienced a real boom within the last few years. In every day medical practice, attending veterinary surgeons extract patient's blood or other autologous tissue samples and process the material for the purpose of administering the resulting product to the same patient under their own responsibility. Although being consistently classified as treatment option within the framework of regenerative medicine, the manufacturing processes, ingredients, and mechanisms of action remain highly diverse among cell-based therapies. Thus, sound knowledge about the latter ones forms the basis for therapeutic decision-making and best possible treatment regimes.

Mesenchymal stem cells for treatment of musculoskeletal disease in horses: Relative merits of allogeneic versus autologous stem cells

Mesenchymal stem cells (MSCs) are widely used for treatment of musculoskeletal diseases in horses, but there is ongoing debate regarding the relative safety and efficacy of allogeneic MSCs, compared with autologous equine MSCs. This review summarises the currently available published data regarding the therapeutic use of autologous and allogeneic MSCs in horses. Arguments that have been advanced against the use of allogeneic MSCs include higher risk of immunological reactions and shorter cell survival times following injection. Arguments favouring the use of allogeneic MSCs include the ability to bank cells and reduce the time to treatment, to collect MSCs from younger donor animals and the ability to manipulate banked cells prior to administration. In vitro studies and a limited set of experimental in vivo studies have indicated that adverse immunological reactions may occur when allogeneic MSCs are administered to horses. However, newer studies lack evidence of inflammatory reactions or adverse clinical responses when allogeneic MSCs are administered and compared with autologous MSCs. Thus, while the relative merits of allogeneic vs autologous MSCs for treatment of musculoskeletal injuries in horses have not been fully established, accumulating evidence from studies in horses suggests that allogeneic MSCs maybe a safe alternative to autologous MSCs. Large, properly designed, randomised trials in addition to careful immunological evaluation of short-term and long-term, local and systemic immune responses are needed to more fully resolve the issue.

Single and repeated intra-articular injections in the tarsocrural joint with allogeneic and autologous equine bone marrow-derived mesenchymal stem cells are safe, but did not reduce acute inflammation in an experimental interleukin-1β model of synovitis

BACKGROUND

Allogeneic and autologous bone marrow-derived mesenchymal stem cells (BMDMSCs) have been administered in equine joints for their anti-inflammatory effects. However, allogeneic BMDMSC offer multiple clinical and practical advantages. Therefore, it is important to determine the relative effectiveness of allogeneic vs autologous BMDMSCs.

OBJECTIVES

The objective of the study was to compare the inflamed joint response to autologous vs allogeneic BMDMSCs injections, and to determine if either treatment generated an anti-inflammatory effect.

STUDY DESIGN

Randomised controlled study.

METHOD

Bone marrow was harvested from eight horses. Autologous BMDMSCs and pooled allogeneic BMDMSCs were culture expanded, cryopreserved and thawed immediately prior to administration. Ten million autologous BMDMSCs were administered with 75 ng rIL-1β into one tarsocrural joint and the contralateral tarsocrural joint received allogeneic BMDMSC plus 75 ng rIL-1β. Repeat injections were performed with the same treatment administered into the same joint. Four additional horses received 75 ng rIL-1β alone in a single tarsocrural joint. Clinical parameters (lameness, joint circumference and joint effusion) and synovial fluid parameters, including nucleated cell count (NCC), differential cell count, total protein (TP), prostaglandin E₂ (PGE₂ ) and C-reactive protein (CRP), were measured at baseline, 6, 12, 24, 72, 168 and 336 hours post-injection.

RESULTS

No difference was detected between autologous and allogeneic treatment groups with respect to subjective lameness, joint effusion, joint circumference, NCC, TP, differential cell count, CRP or PGE₂ . Neither autologous nor allogeneic treatments resulted in an improvement in clinical or cytological parameters over that elicited by rIL-1β alone.

MAIN LIMITATIONS

A single dose of rIL-1β was evaluated and resulted in a severe synovitis which may have been too severe to observe a BMDMSC-mediated effect.

CONCLUSIONS

This study revealed that allogeneic and autologous BMDMSCs resulted in an equivalent clinical and cytological response. Allogeneic and autologous BMDMSCs were equally ineffective in reducing the inflammatory response from acute rIL-1β-induced joint inflammation in horses.

Comparison of efficacy and safety of single versus repeated intra-articular injection of allogeneic neonatal mesenchymal stem cells for treatment of osteoarthritis of the metacarpophalangeal/metatarsophalangeal joint in horses: A clinical pilot study

The purpose of this prospective study was to evaluate the effects of single and repeated intra-articular administration of allogeneic, umbilical cord-derived, neonatal mesenchymal stem cells (MSC) in horses with lameness due to osteoarthritis (OA) of a metacarpophalangeal joint (MPJ).

Twenty-eight horses were included. Horses were divided into two groups. Horses in group MSC1 received an MSC injection at M0 and a placebo injection at M1 (1 month after M0). Horses in group MSC2 received MSC injections at M0 and at M1. Joint injections were performed with a blinded syringe. Clinical assessment was performed by the treating veterinarian at M1, M2 and M6 (2 and 6 months after M0), including lameness evaluation, palpation and flexion of the joint. Radiographic examination of the treated joints was performed at inclusion and repeated at M6. Radiographs were anonymized and assessed by 2 ECVDI LA associate members. Short term safety assessment was performed by owner survey. A 2-month rehabilitation program was recommended to veterinarians. There was a significant improvement of the total clinical score for horses in both groups. There was no significant difference in the total clinical score between groups MSC1 and MSC2 at any time point in the study. There was no significant difference in the total radiographic OA score, osteophyte score, joint space width score and subchondral bone score between inclusion and M6. Owner-detected adverse effects to MSC injection were recorded in 18% of the horses. Lameness caused by OA improved significantly over the 6-month duration of the study after treatment with allogeneic neonatal umbilical cord-derived MSCs combined with 8 weeks rest and rehabilitation. There is no apparent clinical benefit of repeated intra-articular administration of MSCs at a 1-month interval in horses with MPJ OA when compared to the effect of a single injection.

A Feasibility Study on the Use of Equine Chondrogenic Induced Mesenchymal Stem Cells as a Treatment for Natural Occurring Osteoarthritis in Dogs

Conventional treatments of osteoarthritis (OA) reduce pain and the inflammatory response but do not repair the damaged cartilage. Xenogeneic peripheral blood-derived equine chondrogenically induced mesenchymal stem cells (ciMSC) could thus provide an interesting alternative. Six client-owned dogs with confirmed elbow OA were subjected to a baseline orthopedic examination, pressure plate analysis, general clinical examination, hematological analysis, synovial fluid sampling, and radiographic examination, and their owners completed two surveys. After all examinations, a 0.9% saline solution (placebo control product = CP) was administered intra-articularly. After 6 weeks, all examinations were repeated, owners again completed two surveys, and equine ciMSCs were administered in the same joint. After another 6 weeks, dogs were returned for a final follow-up. No serious adverse events or suspected adverse drug reactions were present during this study. No significant differences in blood analysis were noted between the CP and ciMSC treatment. Two adverse events were observed, both in the same dog, one after CP treatment and one after ciMSC treatment. The owner surveys revealed significantly less pain and lameness after ciMSC treatment compared to after CP treatment. There was no significant difference in the orthopedic examination parameters, the radiographic examination, synovial fluid sampling, and pressure plate analysis between CP treatment and ciMSC treatment. A single intra-articular administration of equine ciMSCs proved to be a well-tolerated treatment, which reduced lameness and pain according to the owner's evaluations compared to a placebo treatment.

Intra-Articular Injection of 2 Different Dosages of Autologous and Allogeneic Bone Marrow- and Umbilical Cord-Derived Mesenchymal Stem Cells Triggers a Variable Inflammatory Response of the Fetlock Joint on 12 Sound Experimental Horses

Osteoarthritis is a significant and costly cause of pain for both humans and horses. The horse has been identified as a suitable model for human osteoarthritis. Regenerative therapy with allogeneic mesenchymal stem cells (MSCs) is a promising treatment, but the safety of this procedure continues to be debated. The aim of this study is to evaluate the safety of intra-articular injections of allogeneic MSCs on healthy joints by comparing two different dosages and two different tissue sources, namely, bone marrow and umbilical cord blood, with a placebo treatment on the same individuals. We also assessed the influence of autologous versus allogeneic cells for bone marrow-derived MSC treatment. Twelve clinically sound horses were subjected to injections in their 4 fetlock joints. Each of the three fetlocks was administered a different MSC type, and the remaining fetlock was injected with phosphate-buffered saline as a control. Six horses received 10 million cells per joint, and the 6 other horses received 20 million cells per joint. Clinical and ultrasound monitoring revealed that allogeneic bone marrow-derived MSCs induced significantly more synovial effusion compared to umbilical cord blood-derived MSCs but no significant difference was noted within the synovial fluid parameters. The administration of 10 million cells in horses triggered significantly more inflammatory signs than the administration of 20 million cells. Mesenchymal stem cell injections induced mild to moderate local inflammatory signs compared to the placebo, with individual variability in the sensitivity to the same line of MSCs. Understanding the behavior of stem cells when injected alone is a step towards the safer use of new strategies in stem cell therapy, where the use of either MSC secretome or MSCs combined with biomaterials could enhance their viability and metabolic activity.

The use of equine chondrogenic-induced mesenchymal stem cells as a treatment for osteoarthritis: A randomised, double-blinded, placebo-controlled proof-of-concept study

BACKGROUND

There is a need to improve therapies for osteoarthritis in horses.

OBJECTIVES

To assess the efficacy of equine allogeneic chondrogenic-induced mesenchymal stem cells combined with equine allogeneic plasma as a novel therapy for osteoarthritis in horses.

STUDY DESIGN

Randomised, double-blinded, placebo-controlled experiment.

METHODS

In 12 healthy horses, osteoarthritis was induced in the metacarpophalangeal joint using an osteochondral fragment-groove model. Five weeks after surgery, horses were randomly assigned to either an intra-articular injection with chondrogenic-induced mesenchymal stem cells + equine allogeneic plasma (= intervention) or with 0.9% saline solution (= control). From surgery until the study end, horses underwent a weekly joint and lameness assessment. Synovial fluid was collected for cytology and biomarker analysis before surgery and at Weeks 5, 5 + 1d, 7, 9 and 11. At Week 11, horses were subjected to euthanasia, and the metacarpophalangeal joints were evaluated macroscopically and histologically.

RESULTS

No serious adverse events or suspected adverse drug reactions occurred during the study. A significant improvement in visual and objective lameness was seen with the intervention compared with the control. Synovial fluid displayed a significantly higher viscosity and a significantly lower glycosaminoglycan concentration in the intervention group. Other biomarkers or cytology parameters were not significantly different between the treatment groups. Significantly less wear lines and synovial hyperaemia were present in the intervention group. The amount of cartilage oligomeric matrix protein, collagen type II and glycosaminoglycans were significantly higher in the articular cartilage of the intervention group.

MAIN LIMITATIONS

This study assessed the short-term effect of the intervention on a limited number of horses, using an osteoarthritis model. This study also included multiple statistical tests, increasing the risk of type 1 error.

CONCLUSIONS

Equine allogeneic chondrogenic-induced mesenchymal stem cells combined with equine allogeneic plasma may be a promising treatment for osteoarthritis in horses. The Summary is available in Spanish - see Supporting Information.

Injectable Systems for Intra-Articular Delivery of Mesenchymal Stromal Cells for Cartilage Treatment: A Systematic Review of Preclinical and Clinical Evidence

Stem cell-based therapy is a promising approach to treat cartilage lesions and clinical benefits have been reported in a number of studies. However, the efficacy of cell injection procedures may be impaired by cell manipulation and damage as well as by cell dissemination to non-target tissues. To overcome such issues, mesenchymal stromal cell (MSC) delivery may be performed using injectable vehicles as containment systems that further provide a favorable cell microenvironment. The aim of this systematic review was to analyze the preclinical and clinical literature on platelet-rich plasma (PRP), hyaluronic acid (HA), and hydrogels for the delivery of MSCs. The systematic literature search was performed using the PubMed and Web of science databases with the following string: "(stem cells injection) AND (platelet rich plasma OR PRP OR platelet concentrate OR biomaterials OR hyaluronic acid OR hydrogels)": 40 studies (19 preclinical and 21 clinical) met the inclusion criteria. This review revealed an increasing interest on the use of injectable agents for MSC delivery. However, while negligible adverse events and promising clinical outcomes were generally reported, the prevalence of low quality studies hinders the possibility to demonstrate the real benefits of using such injectable systems. Specific studies must be designed to clearly demonstrate the added benefits of these systems to deliver MSCs for the treatment of cartilage lesions and osteoarthritis.

Injectable Systems for Intra-Articular Delivery of Mesenchymal Stromal Cells for Cartilage Treatment: A Systematic Review of Preclinical and Clinical Evidence

Stem cell-based therapy is a promising approach to treat cartilage lesions and clinical benefits have been reported in a number of studies. However, the efficacy of cell injection procedures may be impaired by cell manipulation and damage as well as by cell dissemination to non-target tissues. To overcome such issues, mesenchymal stromal cell (MSC) delivery may be performed using injectable vehicles as containment systems that further provide a favorable cell microenvironment. The aim of this systematic review was to analyze the preclinical and clinical literature on platelet-rich plasma (PRP), hyaluronic acid (HA), and hydrogels for the delivery of MSCs. The systematic literature search was performed using the PubMed and Web of science databases with the following string: "(stem cells injection) AND (platelet rich plasma OR PRP OR platelet concentrate OR biomaterials OR hyaluronic acid OR hydrogels)": 40 studies (19 preclinical and 21 clinical) met the inclusion criteria. This review revealed an increasing interest on the use of injectable agents for MSC delivery. However, while negligible adverse events and promising clinical outcomes were generally reported, the prevalence of low quality studies hinders the possibility to demonstrate the real benefits of using such injectable systems. Specific studies must be designed to clearly demonstrate the added benefits of these systems to deliver MSCs for the treatment of cartilage lesions and osteoarthritis.