ISOLATION AND IN VITRO CHARACTERIZATION OF FELINE DENTAL PULP STEM CELLS

Abstract

<h3>Background</h3> Mesenchymal stem cells (MSC) have been target of interest during the last years from a therapy perspective due to their unique characteristics of self-renewal, multipotency, "homing" capacity, immunomodulation and angiogenesis. In domestic animals, the most studied type of MSC are those derived from adipose tissue (AT) and have been used for therapy in felines. Another source is the dental pulp, described in humans but not in felines, which may represent an alternative source of stem cells with different characteristics due to their particular embryologic origin. The objective of this research was to isolate and assess the in vitro characteristics and cytogenetic stability of feline dental pulp stem cells (fDPSCs). <h3>Materials and Methods</h3> For this purpose, we studied 2 cultures of fDPSC isolated by overgrowth method. Morphology was assessed by Giemsa staining at passages 2, 4 and 6. Clonogenic capacity was assessed by Colony Forming Units Fibroblast (CFU-F) test and their proliferation by doubling time at passages 2, 4 and 6. Multipotency was assessed by trilineage differentiation (osteogenic, adipogenic and chondrogenic). Cytogenetic studies on these passages were made. <h3>Results</h3> The fDPSC showed spindle shaped and epithelial-like morphology. Feline DPSC were able to form colonies in the analyzed passages. The doubling time was 2.48 and 5.11 days in passage 2 for each sample, 7.61 and 12.28 days in passage 4 and 7.61 and 10.24 in passage 6. Cells were able to tridifferentiate. To assess cytogenetic stability 14 metaphases were analyzed at passage 2, and 47 at passage 4, observing mainly normal karyotypes although structural instability signals were observed such as gaps, breaks, deletions, duplications and early chromatid segregation. <h3>Conclusions</h3> Overgrowth method is appropriate for fDPSCs isolation. The fDPSCs have clonogenic and multipotency capacity in vitro. They maintain their proliferative capacity throughout the three passages analyzed. Signs of chromosomic instability were observed although a larger number of samples are needed to make conclusions about cytogenetic stability. This is the first report of fDPSCs isolation and in vitro characterization.