Differentiation of adult adipose tissue-derived Flk1~+CD31~-CD34~- cells into pancreatic islet-like endocrine cells in vitro / 西安交通大学学报(医学版)

ABSTRACT

Objective To promote the differentiation of Flk1+CD31-CD34-cells isolated from adult adipose tissues into pancreatic islet endocrine cells in vitro.Methods Flk1+CD31-CD34-cells were first cultured and plated in medium supplemented with B27,epidermal growth factor(EGF),and basic fibroblast growth factor(bFGF).Next,the culture medium was changed.The glucose concentration in the serum-free medium was increased.At the same time,betacellulin and nicotinamide were added.Reverse transcription polymerase chain reaction(RT-PCR) was used to detect the expression of nestin,ngn3,insulin promoter factor-1(IPF-1),insulin,and glucagon before and after differentiation induction;immunofluorescent staining for nestin,insulin and glucagon and radioimmunoassay(RIA) for insulin.Results Initially,a nestin positive precursor cell population was found,then small round cells increased in number after 6 days.Later on,they were differentiated into islet-like clusters.The induced cells resulted in the formation of clusters which exhibited higher insulin secretion and other pancreatic endocrine hormones.RT-PCR detected an enhanced expression of pancreatic genes in the differentiated cells.Immunofluorescence revealed a high percentage of insulin-expressing cells in the clusters.Furthermore,the intra-cellular insulin content was detected by RIA after the induction culture.Conclusion These cells represent a previously unidentified adult intrinsic pancreatic precursor population and are a promising candidate for cell-based therapeutic strategies.