Comparison of the characteristics of canine adipose tissue-derived mesenchymal stem cells extracted from different sites and at different passage numbers

Mesenchymal stem cells (MSCs) have desirable characteristics for use in therapy in animal models and veterinary medicine, due to their capacity of inducing tissue regeneration and immunomodulation. The objective of this study was to evaluate the differences between canine adipose tissue-derived MSCs (AD-MSCs) extracted from subcutaneous (Sc) and visceral (Vs) sites. Surface antigenic markers, in vitro differentiation, and mineralized matrix quantification of AD-MSCs at different passages (P(4), P(6), and P(8)) were studied. Immunophenotypic analysis showed that AD-MSCs from both sites were CD44+, CD90+, and CD45−. Moreover, they were able, in vitro, to differentiate into fat, cartilage, and bone. Sc-AD-MSCs preserve in vitro multipotentiality up to P(8), but Vs-AD-MSCs only tri-differentiated up to P(4). In addition, compared to Vs-AD-MSCs, Sc-AD-MSCs had greater capacity for in vitro mineralized matrix synthesis. In conclusion, Sc-AD-MSCs have advantages over Vs-AD-MSCs, as Sc AD-MSCs preserve multipotentiality during a greater number of passages, have more osteogenic potential, and require less invasive extraction.