The Development and use of canine adipose derived stromal and progenitor cells to treat osteoarthritis

Abstract

We evaluated the viability of canine adipose derived stromal cells (ASC) in the presence of osteoarthritic joint fluid, determining that exposure to osteoarthritic joint fluid is more cytotoxic than exposure to normal synovial fluid. We demonstrated that diluting the joint fluid diminishes the severity of this effect. We have demonstrated that a stromal vascular fraction (SVF) preparation of ASCs is phenotypically different from cultured ASCs, having a greater expression of proinflammatory mediator (IL-1β (interleukin-1 beta), COX-2 (cyclooxygenase-2)) and anti-inflammatory mediators (IL-1ra (interleukin-1 receptor antagonist), TIMP-2 (tissue inhibitor metalloproteinase-2) mRNA levels than cultured cells, and greater variability in expression of cell surface markers (MHCI, MHCII, CD90, CD34, CD44 and CD45). We evaluated multiple types of culture media, and found that there is some variation in the previous mentioned markers and mediators, but not a significant difference. Consistent tri-lineage differentiation of ASCs appeared to differ amongst different media types. We concluded that media should be selected according to a phenotypic profile that would be beneficial for the disease the ASC therapy is targeting. We assessed in vivo safety and efficacy of canine autologous SVF and allogeneic ASC therapy in dogs diagnosed with osteoarthritis secondary to a medial coronoid process in the elbow, utilizing objective outcome measures, including ground reaction forces (GRF) and delayed gadolinium enhanced magnetic resonance imaging of cartilage (dGEMRIC). We found no significant deleterious side effects with either therapy, and have produced support for the use of allogeneic ASC therapy.