Tenogenesis of Equine Peripheral Blood-Derived Mesenchymal Stem Cells: In vitro Versus In vivo

Abstract

Background: Tendon injuries are a major cause of orthopaedic injuries, and often compromise the return to the same performance level. Therefore, different regenerative therapies, such as Mesenchymal Stem Cells (MSCs) and Platelet-rich Plasma (PRP) have been explored to improve tendon healing in horses. However, ectopic bone formation of undifferentiated cells is a major concern, because of reports of this phenomenon, after intralesional injections of MSCs in rabbit Achilles tendons. Methods: After MSC and PRP isolation of the Peripheral Blood (PB) of a donor horse, tenogenic induction of the MSCs (Tendo-Cell ®) was confirmed through morphological changes and immunohistochemistry stainings. Secondly, the safety and clinical effects (ultrasound imaging) of Tendo-Cell ® , in combination with PRP, was evaluated after a single intralesional injection in the lateral edge of the Superficial Digital flexor tendon (SDFT) (n=10) and the lateral branch of the suspensory ligament (SL) (n=15) in 25 horses. Different independent veterinary practitioners were asked to give a score from 0-5, at approximately 6 weeks after treatment (0=no ultrasonic improvement and 5=no ultrasonic abnormalities, the tendon has the same consistency and fiber orientation as the contralateral tendon). Results: In 96% of the patients, the same positive evolution was noticed on the ultrasound images, and this was translated to a score 3 or more (≥ 60% improvement or better than a successful conservative therapy). In addition, for both tendons (SDFT & SL), 40% of the horses received a score 5. Conclusion: In conclusion, the present study is the first to describe the treatment of lesions in the SDFT and SL, with allogenic tenogenic induced PB-derived MSCs, in combination with PRP, with a positive outcome in 24 out of the 25 horses.

Equine Epidermis: A Source of Epithelial-Like Stem/Progenitor Cells with In Vitro and In Vivo Regenerative Capacities

“…Three randomly assigned wounds received allogenic putative EpSCs (derived from a slaughter horse skin sample) in combination with autologous PRP (EpSC/PRP-treatment) as a carrier, and the three remaining wounds were treated identically, but without putative EpSCs (PRP injection only). The EpSC/PRP-treatment consisted of two approaches: First, an intradermal injection (0.5 mL in each of the four wound edges) of 1 mL of DMEM containing 8 · 10 6 freshly prepared putative EpSCs at passage 3 in combination with 1 mL of PRP (prepared as previously described [30,33]) was administered. Immediately afterward, a topical application of 0.5 mL DMEM containing 4 · 10 6 putative EpSCs and 0.5 mL of PRP was performed.…”

“…Therefore, the second goal of this study was to compare induced full-thickness skin wounds (positive control), skin wounds treated with EpSCs plus platelet-rich plasma (EpSC/PRP-treated), and skin wounds treated with PRP alone. Since it has been previously indicated that PRP might have synergistic effects on stem cell regeneration [30,31] and that a fibrin-based matrix could support selective adhesion, proliferation, and differentiation of keratinocyte progenitors [32], we elected to use endogenous PRP as a carrier for the EpSCs. Macroscopic and histological examinations revealed significant differences between wound-healing parameters of EpSC/PRP-treated and PRP-treated samples.…”

Tendon Derived Stem Cells Promote Platelet-Rich Plasma Healing in Collagenase-Induced Rat Achilles Tendinopathy

“…Autologous PRP is advantageous for use in patients because it eliminates concerns about immune responses and disease transmission. The safe use of allogenic PRP has also been reported [9,10]. Pre-clinical studies using autologous PRP to promote the healing of tendons or ligaments have shown promising results [30,31,32,33].…”

“…Each cell source has its limitations including inferior proliferation, differentiation and collagen production abilities of tenocytes [12,13,14,15], risk of teratoma formation of ESCs as well as risk of ectopic bone [3] and tumor induction [16] of BMSCs when using a certain scaffold. For this reason, lineage direction of stem cells is recommended prior to their use in cell-based therapies [9,10]. Recently, the more lineage committed tendon derived stem cells (TDSCs), also called tendon stem/progenitor cells, have been identified in a number of species [17,18,19,20].…”

“…A wide range of donor cell types have been used to promote tendon healing in pre-clinical studies, including bone marrow-derived mesenchymal stem cells (BMSCs) [3,4,5], periodontal ligament or gingival tissue [6], dermal fibroblast [7], tenocytes [8], peripheral blood-derived MSCs [9,10] and embryonic stem cell derived MSCs (ESC-MSCs) [11]. Each cell source has its limitations including inferior proliferation, differentiation and collagen production abilities of tenocytes [12,13,14,15], risk of teratoma formation of ESCs as well as risk of ectopic bone [3] and tumor induction [16] of BMSCs when using a certain scaffold.…”