Exploration of Canine Mesenchymal Stromal Cells and Cell Reprogramming for Future Immunotherapy and Cartilage Repair

Date

2017-05-03

Authors

Russell, Keith Andrew

Journal Title

Journal ISSN

Volume Title

Publisher

University of Guelph

Abstract

There are an estimated 6.4 million dogs living in 34% of Canadian households. Dogs suffer from many conditions where only poor to no treatments exist. For example, cartilage injury, osteoarthritis, and other inflammatory disorders have been inadequately remedied by traditional medical care. Increasing effort has been put toward the innovation and optimization of cell-based therapies for tissue regeneration and immune modulation. Approaches include the use of mesenchymal stromal cells (MSC), induced pluripotent stem cells (iPSC), and other cell engineering techniques such as gene over-expression in somatic cells. The hypothesis was that canine cells with immunomodulatory and chondrogenic properties can be isolated from adipose tissue (AT), bone marrow (BM), or articular cartilage (AC) and utilized to generate canine iPSC. The objectives were: 1) to assess the immunomodulatory and chondrogenic properties of canine AT- and BM-MSC and 2) to generate iPSC from canine MSC or chondrocytes and verify their pluripotency and chondrogenesis. Canine MSC were derived from AT and BM. Isolation success and proliferation rates were compared when using two different culture supplements: fetal bovine serum (FBS) and platelet lysate (PL). Despite the fact that PL is slowly displacing use of the increasingly expensive and xenogeneic FBS in human MSC culture, PL proved detrimental to canine MSC. It did not support isolation or long-term culture of MSC and showed evidence of inducing spontaneous adipogenesis. MSC source was also investigated. Few differences were found pertaining to differentiation and immunomodulation. Both MSC populations have good adipogenic and osteogenic, but poor chondrogenic potential, and have proficient lymphocyte suppressive properties. What distinguished AT- from BM-derived MSC were higher proliferation rates. Since MSC were found to be poorly chondrogenic, both canine MSC and chondrocytes were used to generate iPSC. Some signs of reprogramming were apparent. However, the conditions needed to stabilize reprogrammed cells were not yet identified. In conclusion, AT is the recommended source of canine MSC for immunotherapy. A practical source of chondrogenic cells for canine cartilage engineering strategies has not yet been established, but this work is a promising starting point for further study.

Description

Keywords

canine, dogs, mesenchymal stromal cell, MSC, iPSC, cell reprogramming, differentiation, immunomodulatory, immune cell suppression, stem cells, regenerative medicine, cell culture, FBS, platelet lysate, chondrocytes, immunophenotyping

Citation