A Preliminary Study On The Promotion Of Hematopoietic Stem Cell Proliferation By Adipose Tissue-Derived Stem Cells In Vitro

Objective:To investigate the ability and mechanism of adipose tissue-derived stem cells(ADSCs)in promoting the proliferation of hematopoietic stem cells(HS Cs)in vitro.Methods:ADSCs,Bone marrow mesenchymal stem cells(BMSCs)and Fibroblast cells(RF)were prepared under aseptic conditions in vitro,and cultured to the third generation.Lin~-Scal-1~+C-kit~+(LSK)were separated by Magnetic cell se-paration(MACS),Cell morphology was observed.The first step was to divide the experiment into two groups:(1)ADSCs+LSK.(2)BMSCs+LSK;In long-term co-culture in vitro,LSK cells were counted by counting plate,and the gene expression level of Notch signaling pathway in LSK cells after co-culture was detected by fluoresce-nce quantitative PCR.In the second step,the experiment was divided into four grou-ps:(1)ADSCs+LSK;(2)ADSCs+LSK+Gamma-secretase inhibitors(GSI);(3)RF+LSK;(4)RF+LSK+GSI;The above four groups were co-cultured in long-term medium for 0,14 and 35 days.The morphology of ADSCs and RF were observed,and LSK amplification was monitored.The proliferation status of LSK colonies was analyzed with methyl cellulose,and LSK cells were selected for counting.Results:1.ADSCs and BMSCs promoted LSK amplification equally on the 14th day,while on the 35th day,ADSCs had stronger ability to amplify LSK cells than BMSCs.On the 14th day,the expression level of Notch signaling pathway genes in LSK cells in ADSCs group was lower than that in BMSCs group,while on the 35th day,the expr-ession level of Notch signaling pathway genes in LSK cells in ADSCs group was higher than that in BMSCs group,especially the downstream signal Hes-1.2.In the non-GSI group,the total number of LSK cells in the ADSCs group was significantl-y higher than that in the RF group on the 14th or 35th day.Compared with the A DSCs group,the count of LSK cells in the ADSCs group without GSI was signific-antly higher than that in the ADSCs group with GSI,and the difference was statisti-cally significant(P<0.05).Conclusion:ADSCs have longer and stronger hematopoi-etic supporting capacity than BMSCs in vitro culture,and may promote the prolifera-tion of LSK cells by activating the Notch signaling pathway.