The Study Of Difference Between Induced Pluripotent Stem Cells And Its Ability To Differentiate Into Melanocyte

Objective The process of induced pluripotent stem cells(i PS cells)differentiate into melanocyte took a lot of time and money due to the different function and differentiation ability among i PS cells.In order to choose better quality i PS cells to conduct the further study of differentiation,it is necessary to evaluate the quality of i PS cells.The purpose of this study to explore the difference between the function of i PS cells and its ability differentiate into melanocyte.Methods(1)Try to prepare i PS cell lines and to test their functions in many ways,such as alkaline phosphatase activities,stem cell markers,stem cell genes,the ability of forming teratoma.(2)Try to differentiate i PS cells into melanocyte,then to identify the melanocyte preliminary.(3)According to the analysis the function of i PS cells,we observed whether the i PS cell could differentiate into melanocyte or not.Then to explore the difference between the function of i PS cells and its' ability to differentiate into melanocyte.Results(1)In terms of Alkaline phosphatase staining,all i PS cells could positive expression of AP,which showed that those i PS cells were undifferentiated.While the AP positive clones in i PSC-1 was more activite than that of i PSC-2 and i PSC-3,which demonstrated that the i PSC-1 had higher alkaline phosphatase activity.(2)In the expression of stem cell markers,all i PS cells could express stem cell markers(OCT4 and NANOG).The location of stem cell markers in i PSC-1 was closed together than that of i PSC-2 and i PSC-3,which illustrated that cells of i PSC-1clone were more compacted.(3)In the gene expression,all i PS cells could express stem cell genes(Oct4?Sox2?Nanog?Rex1?GDF3?DNMT3B),which showed that all of them had pluripotency.But the expression level of stem cell genes were higher in i PSC-1 than i PSC-2 and i PSC-3,which demonstrated i PSC-1 had better pluripotency.(4)In the respect of forming embryiod bodies(EB)in vitro,the EB from i PSC-1had better morphology and more clear boundary than hat from i PSC-2 and i PSC-3 at the first day.The volume of the EB from i PSC-1 was lager than that from i PSC-2 and i PSC-3 an the third day,which illustrated the rate of growth of the EB from i PSC-1was faster than that of i PSC-2 and i PSC-3.It showed that i PSC-1 had better ability of differentiation in vitro.(5)In terms of the ability of forming teratoma,we observed that after two months of injecting i PS cells into immunodeficient mice,only i PSC-1 could form teratoma while i PSC-2 and i PSC-3 could not,which illustrated that i PSC-1 had pluripotency in vivo.(6)In the respect of directional differentiation into melanocyte in vitro,only i PSC-1could differentiated into melanocyte-like cells.After the observation of the morphology of cells and the colour of the cell sediment and the test of relative melanocyte genes,we assured that only i PSC-1could differentiated into melanocyte,while i PSC-2 and i PSC-3 could not.Conclusions There were different functions among i PS cells.i PS cells with higher alkaline phosphatase activity,higher expression level of stem cell markers and stem cell genes,the better morphology of EB and the ability of forming teratoma could successfully differentiate into melanocyte.That's to say,the better of the i PS cells were,the stronger ability to differentiate into melanocyte.The different function of i PS cells determined its' different ability to differentiate into melanocyte.