In the present study we provided a morphological and transcriptomic comparison of adult porcine adiposederived stem cells (ADSC) and bone marrow-derived stem cells (BMSC) as they differentiated in vitro towards the osteogenic and adipogenic lineages for up to 4 weeks. The long term goal of this comparison is to assess the possibility of using ADSC as a potential alternative to BMSC as a source of autologous adult stem cells in human therapies.
Our data indicated that ADSC can differentiate into osteocytes and adipocytes similar to BMSC but with some differences. During the osteogenic differentiation both cell types went through morphological changes; however, while ADSC formed predominately osteogenic islands (nodules) in the culture dish, BMSC formed a continuous osteogenic sheet of small nodules. Transcriptomic analysis revealed that both cell types responded to the osteogenic induction. However, BGLAP mRNA expression did not increase in ADSC suggesting, together with the percentage area stained observed for Alizarin Red and von Kossa in ADSC, a lesser mineralization of bone matrix in this cell type compared to BMSC.
During the adipogenic induction ADSC as well as BMSC were able to achieve the morphological and transcriptome changes characteristic of the adipogenic lineage. After 7 days of differentiation the expression patterns of DGAT2 and ADFP became greater in ADSC versus BMSC, which agreed with the larger lipid droplets formation observed in the ADSC by Oil Red O staining.
Our findings represent an important step towards the assessment of using ADSC as an alternative to BMSC in therapeutic applications.