ABSTRACT
Objective To study the immunogenicity of human embryonic stem cells(hESCs)and the derived neural stem cells(NSCs)in vitro.Methods The constitutive expression of human leucocyte antigen(HLA)Ⅰ and Ⅱ in hESCs and the NSCs derived from these hESCs were detected by flow cytometry (FCM), as well as the expression of HLA-Ⅰ,Ⅱin NSCs induced by 30 ng/ml recombination human interferon-?(IFN-?).Meanwhile, the NSCs before and after induction of IFN-? were co-cultured with peripheral blood lymphocyte obtained from healthy person.Lymphocyte proliferation standing for the immunoreactivity of NSCs was then investigated.Results The hESCs slightly expressed HLA-Ⅰ(6.18%) and hardly any HLA-Ⅱ before differentiation.However, the NSCs expressed more HLA-Ⅰ(23.56%)as well as HLA-Ⅱ(1.28%, 1.73%)than the hESCs did.Both HLA-Ⅰ(46.43%)and HLA-Ⅱ(8.73%, 10.57%)expressed by the NSCs after they were induced by IFN-? were up-regulated.Conclusions hESCs express certain level of HLA-Ⅰ molecules but do not constitutively express HLA-Ⅱ molecules.The derived NSCs express heavy HLA-Ⅰ and a little HLA-Ⅱ, when treated by IFN-? they can inducibly up- regulated both molecules.The NSCs derived from HESCs are of immunogenicity, which induce rejection aiming at HLA-Ⅰ molecules or even at HLA-Ⅱ molecules when the host is inflammative or under stress, which can result in a failure of cellular transplantation.
ABSTRACT
Objective To explore a kind of simple and high efficient approach to differentiate human embryonic stem cells(hESCs)into neural stem cells(NSCs).Methods hESCs were cultured in bacterial culture dish filled with serum free medium to gain embryoid bodies.Then the mature embryoid bodies grew in the special medium including B27 and noggin by adherent culture to differentiate into NSCs. Results The hESCs kept floating in the bacterial culture dish and growing all the time and then formed mature embryoid bodies 7 to 10 days later.The embryoid bodies could be differentiated into highly pure (96.4%)nestin positive cells.And these cells were differentiated into all kinds of neural cells if cultured further.Conclusions This kind of method is less time-consuming,cheaper,and more efficient than those of the results in literatures reported.It affords very good source of seed cells for cell transplantation therapy in the future.