HBV特异CTL非溶细胞性机制清除肝细胞中HBV的研究进展

一般认为，HBV是一种非细胞病理性的具有包膜的双链DNA病毒，其感染肝细胞引发的急、慢性肝炎是人体免疫系统在清除HBV感染的过程中对肝细胞破坏的结果。在免疫系统清除肝细胞中HBV时，起核心作用的是HBV特异的细胞毒T淋巴细胞（CTL，为活化的CD8^＋T细胞），CTL主要通过Fas-FasL细胞凋亡途径、穿孔素-颗粒酶途径破坏HBV感染的肝细胞，以达到清除HBV的目的。

HBsAg疫苗对非溶细胞性和溶细胞性细胞免疫应答的影响

目的:观察 HBsAg 疫苗对细胞免疫应答的影响及其诱生的免疫反应类型.方法:低、中、高剂量 HBsAg 疫苗两次免疫小鼠后,采用酶联免疫法检测鼠血清抗 HBsIgG2a,并用乳酸脱氢酶分析法检测细胞毒性 T 淋巴细胞(CTL)杀伤靶细胞的活性.结果:HBsAg 疫苗可诱导小鼠产生抗 HBsIgG2a,中、高剂量组阳转率(91.1%、100%)显著高于低剂量组(62.5%),P 均<0.01;低、中、高剂量组部分鼠特异性 CTL 释放率大于60%,达到特异性 CTL 活化(60%、60%、56%),与对照组(0%)比较 P 均<0.01结论:HBsAg 疫苗可增强特异性细胞免疫反应,而且对非溶细胞性和溶细胞性免疫应答均可上调.

非溶细胞性抗病毒作用机制的研究进展

本文综述了非溶细胞性作用控制病毒感染的研究进展,并着重指出了细胞因子在这一过程中的地位。即直接激活抗病毒作用以及通过调节免疫反应上调病毒抗原决定簇在感染细胞表面的呈递和表达,从而间接控制病毒感染。

Soluble forms of extracellular cytokeratin 18 may differentiate simple steatosis from nonalcoholic steatohepatitis

AIM: To investigate whether serum levels of two soluble forms of extracellular cytokeratin 18 (M30-antigen and M65-antigen) may differentiate nonalcoholic steatohepatitis (NASH) from simple steatosis in patients with nonalcoholic fatty liver disease (NAFLD). METHODS: A total of 83 patients with suspected NAFLD and 49 healthy volunteers were investigated. Patients with suspected NAFLD were classified according to their liver histology into four groups: definitive NASH (n = 45), borderline NASH (n = 24), simple fatty liver (n = 9), and normal tissue (n = 5). Serum levels of caspase-3 generated cytokeratin-18 fragments (M30-antigen) and total cytokeratin-18 (M65-antigen) were determined by ELISA. RESULTS: Levels of M30-antigen and M65-antigen were significantly higher in patients with definitive NASH compared to the other groups. An abnormal value (> 121.60 IU/L) of M30-antigen yielded a 60.0% sensitivity and a 97.4% specificity for the diagnosis of NASH. Sensitivity and specificity of an abnormal M65-antigen level (> 243.82 IU/L) for the diagnosis of NASH were 68.9% and 81.6%, respectively. Among patients with NAFLD, M30-antigen and M65-antigen levels distinguished between advanced fibrosis and early-stage fibrosis with a sensitivity of 64.7% and 70.6%, and a specificity of 77.3% and 71.2%, respectively. CONCLUSION: Serum levels of M30-antigen and M65-antigen may be of clinical usefulness to identify patients with NASH. Further studies are mandatory to better assess the role of these apoptonecrotic biomarkers in NAFLD pathophysiology.

Prevention of febrile nonhemolytic transfusion reaction with leucocyte filtrated concentrates

Objective: To assess the clinical efficiency of the transfusion of leucocyte filtrated RBC concentrates to prevent febrile nonhemolytic transfusion reactions (FNHTRs). Methods: One hundred patients with liver cirrhosis, gastric ulcer or cancer were subjected to receive RBC concentrates after leucocyte filtration. Another 50 patients with similar diseases were selected to receive non-filtrated RBC concentrates. The incidence of FNHTRs in all patients was investigated. Results: There was no FNHTR in 100 transfusions with leucocyte filtrated RBC concentrates, while FNHTRs occurred in 8 of 50 patients with non-filtrated RBC concentrates, with the incidence of 16%. Conclusion: FNHTRs to RBC transfusion can be prevented with leucocyte filtration.

肝内乙肝病毒cccDNA的研究进展

肝内HBVcccDNA被认为在乙肝病毒持续感染中是停药反跳和病毒耐药的关键因素.本文就肝内HBVcccDNA的产生、属性、检测方法、清除机制,及与现有抗病毒治疗的关系,作了综述.期望为终结乙肝病毒持续感染提供一些理论基础.