Lore Van Hecke

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

The safety of the intra-articular use of mesenchymal stem cells (MSCs) is scarcely reported. Therefore, the goal of this study was to investigate the safety of a single intra-articular injection with allogeneic chondrogenic induced MSCs combined with equine plasma (=the investigational product: IVP) compared to a saline (0.9% NaCl) placebo control (=control product: CP). Sixteen healthy experimental horses were randomly assigned to receive a single intra-articular injection with either the IVP (n=8) or the CP (n=8) in the left metacarpophalangeal joint. All horses underwent a daily clinical assessment throughout the entire study period of 42days to assess adverse events. Additionally, a local joint assessment and a lameness examination were performed daily during the first two weeks, and weekly the following 4weeks. Blood samples were taken weekly for hematological and biochemical analysis. At the end of the study period, horses of the IVP group were euthanized for a thorough necropsy and to check for biodistribution. Tissue samples of the injected joint were collected for histological examination. In both CP and IVP treated horses a mild transient subjective increase in periarticular temperature and lameness was noted after the intra-articular injection with no significant differences between the treatment groups. No distribution of the cells was found using immunohistochemistry and no ectopic tissue formation or signs of inflammation were found on histology. A single intra-articular injection of allogeneic chondrogenic induced MSCs combined with allogeneic plasma in horses had the same clinical side effects as an intra-articular injection with saline solution.

Wound-healing markers after autologous and allogeneic epithelial-like stem cell treatment

BACKGROUND AIMS Several cytokines and growth factors play an essential role in skin regeneration and epithelial-like stem cells (EpSCs) have beneficial effects on wound healing in horses. However, there are no reports available on the expression of these growth factors and cytokines after EpSC therapy. METHODS Wounds of 6 cm(2) were induced in the gluteus region of 6 horses and treated with (i) autologous EpSCs, (ii) allogeneic EpSCs, (iii) vehicle treatment or (iv) untreated control. Real time polymerase chain reaction was performed on tissue biopsies taken 1 and 5 weeks after these treatments to evaluate mRNA expression of interferon (IFN)-γ, interleukin (IL)-6, vascular endothelial growth factor (VEGF), epidermal growth factor (EGF), insulin-like growth factor (IGF)-1 and epidermal keratin (eKER). RESULTS One week after treatments, mRNA levels of IL-6 (P = 0.012) and VEGF (P = 0.008) were higher in allogeneic EpSC-treated wounds compared with controls. Also, mRNA levels of IGF-1 were higher at 1 week in both autologous (P = 0.027) and allogeneic (P = 0.035) EpSC-treated wounds. At week 5, all EpSC- and vehicle-treated wounds demonstrated significantly higher IFN-γ, VEGF and eKER mRNA expression compared with controls and compared with their respective levels at week 1. CONCLUSIONS Equine wounds treated with allogeneic EpSCs demonstrate a significant increase in mRNA expression of IL-6, VEGF and IGF-1 in the acute phase. In the longer term, an increase in IFN-γ, VEGF and eKER mRNA was detected in the wounds treated with allogenic EpSCs, autologous EpSCs or their vehicle.

The antibacterial effect of vacuum-assisted closure (VAC) using 3 different foams in an equine perfused ex vivo wound model

Introduction: Osteoarthritis (OA) begins many years before structural changes are detectable, since DJD spans over a lifetime in man. In racehorses progression from post-traumatic OA stage to DJD seems much shorter. The purpose of this study was to assess changes in inflammatory and structural biomarkers in serum (S) and synovial fluid (SF) in a cohort of STBRs diagnosed with post-traumatic fetlock OA over the racing career of the animals. We hypothesised that biomarkers assay could demonstrate the progression of degenerative status in the joints after post-traumatic OA, better than clinical and radiographic assessment.