Biological character of human adipose-derived adult stem cells and influence of donor age on cell replication in culture

Abstract

To investigate the biological character of human adipose-derived adult stem cells (hADAS cells) when cultured in vitro and the relationship between hADAS cell's replication activity and the donor's age factor, and to assess the stem cells as a new source for tissue engineering. hADAS cells are isolated from human adipose tissue of different age groups (from adolescents to olds: <20 years old, 21-40 years old, 41-60 years old and >61 years old groups). The protein markers (CD29, CD34, CD44, CD45, CD49d, HLA-DR, CD106) of hADAS cells were detected by flow cytometry (FCM) to identify the stem cell, and the cell cycle was examined for P20 hADAS cells to evaluate the safety of the subculture in vitro. The generative activity of hADAS cells in different age groups was also examined by MTT method. The formula "TD = t x log2/logNt - logN0" was used to get the time doubling (TD) of the cells. The results showed that the cells kept heredity stabilization by chromosome analysis for at least 20 passages. The TD of these cells increased progressively by ageing, and the TD of the <20 years old group was lower than that of the >61 years old group (statistical analysis of variance (ANOVA), P=0.002, P<0.05). These findings suggested that a higher level of hADAS cells replication activity was found in the younger donators, and they represent novel and valuable seed cells for studies of tissue engineering.

Adipose‐derived stem cell: a better stem cell than BMSC

“…About CD34 expression, there are many different (14), ADSCs after being subcultured from P20 every 14 days reports. 10,18,28,29 Some researchers reported that ADSC can express CD34, 18,28 but this is different from our results and of some others. 10,29 It is possible that at the early time of culture, some hematopoietic cells may be mixed with the cultured cells.…”

“…8 While others obtained different numbers of ADSCs from adipose tissue with some different methods. 9,10 All these data indicate that with diverse isolation methods, different amount of ADSCs could be obtained from equal quantities of adipose tissue. If we want to obtain enough high quality cells for tissue engineering and regeneration therapy, a better and simple isolation method must be developed.…”

“…10 However, it has been demonstrated that protein synthesis in ADSCs continuously increased over 2 weeks. 11 Therefore, the detailed growth characteristics of ADSCs are not well understood to date.…”

“…Others need longer times and gain fewer cloned cells. 10,19 Moreover, BMSCs took a markedly longer period of time to reach to 90% confluence, typically 1 week. 20 Nearly all growth curves of stem cells including BMSC and ADSC appear to reach a platform phase at the 6th or 7th day.…”

“…These are similar to the results reported by others previously. 10 Therefore, the less subculture, the less lesion to the cells since passage operation can impair cells.…”