培门冬酶通过干扰mTOR信号通路治疗EB病毒相关噬血细胞综合征的机制研究

EBV相关噬血细胞综合征（EBV-HLH）是一种进展迅速、高死亡率的危重疾病。我们前期发现培门冬酶可显著降低EBV-HLH患者的EBV-DNA，但机制不清。前期发现培门冬酶促进EBV(+)细胞株和EBV-HLH患者PBMC的凋亡。据报道培门冬酶耗竭门冬酰胺可能抑制mTOR通路。据此提出假说：培门冬酶治疗EBV-HLH的可能机制为培门冬酶耗竭EBV感染细胞的门冬酰胺，抑制mTOR通路，促进细胞凋亡，降低EBV-DNA。本研究拟应用质谱流式技术分析1、培门冬酶对EBV(+)细胞株和EBV-HLH患者PBMC的mTOR信号通路、细胞凋亡和EBV-DNA的作用。2、门冬酰胺阻断培门冬酶的作用。3、生长因子活化mTOR通路及mTOR抑制剂对上述标记物和EBV-DNA的影响。旨在探索EBV-HLH的发病机制，培门冬酶治疗EBV-HLH的可能机制，为改善这一危重症的生存提供理论依据。

Epstein–Barr virus-associated hemophagocytic lymphohistiocytosis (EBV-HLH) is a rare life-threatening disease. In our center, we have used the PEG-aspargase of principal combination regimen to treat EBV-HLH patients who have not achieved response on the HLH-94 regimen and achieve encouraging effect, and EBV-DNA was reduced even to 0 copy/ml after PEG-aspargase regimen. But the role of PEG-aspargase therapy for EBV-HLH is unclear.The apoptotic effects of PEG-Asp on EBV positive cell line and PBMC extracted from EBV-HLH patients were observed in a couple of in vitro experiments. It has been reported that asparagine depletion may inhibit the mTOR pathway. Therefore, we hypothesize that the potential mechanism of PEG-aspargase in the treatment of EBV-HLH is that the mTOR pathway was inhibited and the EBV-DNA replication was disrupted by L-asparagine depletion. To test this hypothesis, this proposed study will evaluate that the replication of EBV positive cells is through mTOR pathway, and that the PEG-aspargase may inhibit this pathway, and evaluate the effects of asparagine blocks the enzyme, growth factors on mTOR pathway activation and mTOR inhibitors on related markers and EBV-DNA through CyTOF flow cytometry. The above study is designed to verify the role of PEG-aspargase therapy for Epstein–Barr virus-associated hemophagocytic lymphohistiocytosis, to improve the treatment status of this severe disease, and to provide a theoretical basis for improving survival.