Comparative Analysis of Mesenchymal Progenitor Cells from Dental Pulp and Cord Tissue and their Potentiality Towards Trans-Differentiation

Abstract

Objective: The objective of our study was to successfully isolate progenitor cells from dental pulp and umbilical tissue and perform a comparative investigation of their potential transdifferentiation into osteo- and neuronal-like cells. Methods: Progenitor cells were harvested from dental pulp tissue as well as cord tissue and cultured through explant culture method over the span of 4 weeks. Image-based cytometric analysis was done to determine the cell viability along with phenotypic analysis to validate the occurrence of stem cell surface markers such as CD13, CD29, CD31, CD34, CD45, CD73, CD90, CD105, HLA-DR, and HLA-ABC. After culturing mesenchymal progenitor cells, osteogenic and neurogenic differentiation potential of both tissue sources was studied. The cells were seeded in two different surfaces tissue culture treated dishes and titanium sheets and cultured along with osteogenic differentiation medium (for 28 days) and neurogenic differentiation medium (for 5 days). The osteogenic potential of the progenitor cells were checked with the detection of calcium deposits by Vonn Kossa staining and PCR studies were done to confirm the presence of osteogenic genes like BMP2, HDAC1, HNF1A. The neurogenic potential of the progenitors were phenotypically determined by the observation of neuronal cells in the culture medium. Post differentiation PCR studies were done to confirm the presence of neuronal genes like NESTIN, AGRIN, MAG, DAPDH, NF-M. Findings: Progenitor cells extracted from cord tissue and dental pulp were positive for markers such as CD13, CD29, CD73, CD90, and CD105 and were found negative for markers such CD31, CD34, CD45, and HLA-DR. Progenitors obtained from dental pulp tissue showed a higher expression of cell surface markers indicating a stronger mesenchymal lineage. After culturing progenitor cells in osteogenic differentiation specific medium, these cells were successfully differentiated into cells of osteogenic lineage. Within 28 days of culture calcium deposits were detected by Von kossa staining. The differentiated cells were also found positive for osteogenic markers such as BMP2, HDAC1, HNF1A.In neural differentiation, post day 5 of culture neurospheres of varying sizes were observed floating in the culture medium. The fraction of the cells differentiated into osteogenic and neurogenic lineages were higher in progenitor cells derived from dental pulp in comparison with umbilical cord tissue. The higher potentialityof progenitor cells derived from dental pulp for neurogenic trans-differentiation could be explained by the fact that human adult dental pulp stem cells residing within the perivascular niche are thought to originate from the migrating cranial neural crest cells. There was no difference observed in the osteogenic and neurogenic differentiation capabilities of mesenchymal cells when plated in a plastic dish or titanium surface. Improvement: In-depth studies needs to be carried out on progenitor cells from dental pulp tissues in order to enhance the clinical efficacy of stem cells based therapies.