Characterization and Multilineage Differentiation of Domestic and Black-Footed Cat Mesenchymal Stromal/Stem Cells from Abdominal and Subcutaneous Adipose Tissue

Transplantation of mesenchymal stem cells (MSCs) isolated from bone marrow or adipose tissue is emerging as a promising tool for cell replacement therapy and regenerative medicine in domestic and endangered animal species. Defining the differentiation capability of adipose-derived mesenchymal stromal/stem cells (AMSCs) collected from different depot sites of adipose tissue will be essential for developing strategies for cell replacement therapy. In the present study, we compared the biological characteristics of domestic cat AMSCs isolated from visceral fat of the abdominal cavity (AB) with AMSCs from subcutaneous (SQ) tissue, and the functional capability of domestic and black-footed cat (Felis nigripes) AMSCs to differentiate into other cell types. Our results showed that both domestic and black-footed cat adipose–derived stromal vascular fractions contained AMSCs. Both domestic cat AB- and SQ-AMSCs showed important clonogenic ability and the minimal MSC immunophenotype as defined by the International Society for Cellular Therapy in humans. However, domestic cat AB-AMSCs had higher percentages of cells positive for MSCs-associated cluster of differentiation (CD) markers CD90⁺ and CD105⁺ (92% and 80%, respectively) than those of SQ-AMSCs (77% and 58%, respectively). Although these results may suggest that AB-AMSCs may be more multipotent than SQ-AMSCs, both types of cells showed similar expression of pluripotent genes Oct-4 and Klf4, except for higher expression of Nanog than in AB-AMSCs, and equivalent in vitro multilineage differentiation. Under appropriate stimuli, the black-footed cat and both domestic cat AB- and SQ-AMSCs differentiated not only toward mesoderm cell lineages but also toward ectoderm cell lineage, such as neuron cell–like cells. Black-footed cat AMSCs had more capability to differentiate toward chondrocytes. These results suggest that the defined AMSC population (regardless of site of collection) could potentially be employed as a therapeutic agent for both domestic and endangered diseased or injured felids.