[Induction of tolerogenic dendritic cells by membrane-bound HLA-G in vitro].

In order to study how to induce tolerogenic dendritic cells in vitro and its mechanism, the K562 cells transduced with HLA-G construct were used to co-culture with DC. Then their related immunological changes, such as membrane molecules CD80, CD86, ILT3 and ILT4 expression levels were detected by flow cytometry. Allogeneic proliferation of peripheral blood mononuclear cells (PBMNC) was detected by mixed lymphocyte reaction. The results showed that CD80 and CD86 expressions on DC were downregulated, while ILT3 and ILT4 expressions were upregulated after co-culturing with K562-HLA-G cells. The DCs were less able to stimulate the allogenic PBMNC. It is concluded that the membrane-bound HLA-G can upregulate expression of inhibitory receptors ILT3 and ILT4, inducing tolerogenic DC in vitro, which may provide a novel strategy for transplant tolerance induction.