Evaluation of the quality of life-enhancing effect of allogeneic feline adipose mesenchymal stem cells in cats with osteoarthritis: A pilot study

Osteoarthritis (OA) is a progressive degenerative disease in older cats, and often leads to decreased quality of life (QOL). Mesenchymal stem cells (MSCs) have been used in novel therapies for inflammatory diseases. We aimed to evaluate quantitatively allogeneic adipose-derived MSC (ADSC) therapy in cats with naturally occurring OA, based on QOL assessment resources. To characterize the in vitro properties of ADSCs, we estimated ADSCs from four healthy cats with respect to morphology, differentiation potential, and immunomodulatory potential. Six cats with OA were administered a single intravenous injection of allogeneic ADSCs. Based on the feline musculoskeletal pain index (FMPI), the outcome measure was QOL. The cultured cells were adherent, exhibited a spindle shape without becoming flattened or large, and maintained doubling time until passage 5. After induction, the cells had osteogenic, adipogenic, and chondrogenic phenotypes. These cells expressed CD44 and CD90 and lacked expression of CD14 and CD45, had significantly suppressed the production of interferon -ɤ released from mitogen-stimulated lymphocytes (P < 0.05). The FMPI of all cats with OA significantly increased one month after ADSC therapy (P < 0.05). No adverse effects associated with ADSC administration were observed during follow-up in any of the cats. In conclusion, ADSC therapy with immunomodulatory potential could have beneficial effects on the QOL in cats with OA. Further research is necessary to carry out larger studies of the effectiveness of ADSC therapy.