T淋巴细胞内mTOR/S6途径在难治/复发再生障碍性贫血发病机制中的作用

Objective To explore the activation status of signal pathway of mTOR/S6 in bone marrow(BM) T lymphocytes of refractory/relapsed aplastic anemia patients(AA),and the effects of rapamycin (RAPA)and CTLA-4 immunoglobulin(CTLA-4 Ig)on this pathway.Methods BM was collected from 13refractory/relapsed AA patients,8 newly diagnosed severe AA(SAA)patients and 10 iron deficiency anemia (IDA)(as controls)patients,and cocultured with RAPA and CTLA-4 Ig.The expression of p-mTOR,p-S6 and Interferon γ(IFN-γ)in CD3+ T cells was measured by flow cytometry(FCM).Results ①The expression of p-mTOR,P-S6 and IFN-γ in CD3+ T cells in refractory/relapsed AA group were significantly higher than those in controls(P＜0.01).②The expression of P-mTOR and p-S6 in T cels in newly diagnosed SAA group,Was similar to those in controls(P＞0.05),but significantly lower than those in refractory/relapsed AA group(P＜0.01).The expression level of IFN-γ in T cells were significantly higher than that in controls (P＜0.01).③On exposure to RAPA,The levels of p-mTOR,p-S6 and IFN-γ in T cells in refractory/relapsed AA patients were significantly lower than those before the exposure(all P＜0.05).And so were when exposed to CTLA-4 Ig(all P＜0.01).Conclusion ①The mTOR/S6 signal pathway is activated in refractory/relapsed AA.②The expression of p-mTOR,p-S6 and IFN-γ in refractory/relapsed AA Can be suppressed by RAPA or CTLA-4 Ig.③The signal pathway of CD28/mTOR/S6/IFN-γ might take part in immune pathogenesis of refractory/relapsed AA.

The role of intracellular signal pathway of mTOR/S6 in CD3+T lymphocytes of refractory/relapsed aplastic anemia patients