Effects of interleukin-1β at different concentrations on differentiation of rat adipose derived stem cells into chondrocytes in vitro

Objective To investigate the effects of interleukin-1β (IL-1β) at different concentrations on the differentiation of adipose derived stem cells (ADSCs) into chondrocytes in vitro.Methods ADSCs were successfully isolated,cultured and identified in vitro from SD rats.According to the preliminary results,the experiments were performed in 4 groups (3 experimental and one control ones) with 12 samples in each.The same quantity of cells (1 × 105) was used in each group.IL-1β at concentrations of 1 ng/mL,2ng/mL and 3 ng/mL was added respectively in experimental groups A,B and C.At 6,12 and 18 days after culture,the gene expression levels of cartilage formation (type Ⅱ collagen and glycosaminoglycan protein) and lipoid formation (fatty acid binding protein) were detected using RT-PCR.Results Immunochemistry showed positive expression of CD44 and CD105 in ADSCs.At 6,12 and 18 days after culture,the expression levels of type Ⅱ collagen and glycosaminoglycan protein in group B were significantly increased than in the control group(P ＜ 0.05).There were no such significant differences between groups A and C,or between the control group and groups A and C respectively (P ＞ 0.05).At 6,12 and 18 days after culture,the expression of fatty acid binding protein was significantly higher in group A than in the control group and group B,and significantly lower in group B than in the control group(P ＜ 0.05),but there was no significant difference between group C and the control group (P ＞ 0.05).Conclusion IL-1 β at concentrations of 1 ng/mL and 3 ng/mL has no significant effect on the differentiation of ADSCs into chondrocytes in vitro,but IL-1β at a concentration of 2 ng/mL may have. Key words: Adipose tissue;  Stem cells;  Interleukin-1 ;  Chondrocytes;  Induction