Passage- and serum-dependent changes of adipose-derived stromal cells

Objectives: Autologous fat transplantation is a promising source for cell therapy and tissue engineering. However, the physiological function and regulatory mechanisms of Methods: In this study, we compared the expression of stemness-defining surface markers according to the minimal criteria definition (CD 11b⁻, CD 31⁻, CD 34⁻, CD 45⁻, CD 73⁺, CD 90⁺, and CD 105⁻) by flow cytometry analysis with the expression of stemness-related genes such as MCAM, OCT4, MYC, and cKit in hASCs cultured in either fetal calf serum (FCS) or human serum (HS) supplemented medium from passage 0 to 5. Results: As expected, we found that hASCs in both groups retained their typical mesenchymal surface marker profile CD 73 and CD 90 (>95 %) in flow cytometry analysis, as well as the absence of CD 11b, CD 31, CD 34, and CD 45 (<5 %) until passage 5. However, in contrast to that, RT-PCR indicated a passage-dependent decline and medium-dependent changes in the transcriptome, in particular the loss of the stemness-related genes cKit and MCAM in both groups, while MYC and OCT4 showed unpredictable expression. Conclusions: Summarized, these results indicate the need for standardized cell culture protocol, as the transcriptome seems to change during