Innate immune recognition and modulation in hepatitis D virus infection

Hepatitis D virus(HDV) is a global health threat with more than 15 million humans affected. Current treatment options are largely unsatisfactory leaving chronically infected humans at high risk to develop liver cirrhosis and hepatocellular carcinoma. HDV is the only human satellite virus known. It encodes only two proteins, and requires Hepatitis B virus(HBV) envelope protein expression for productive virion release and spread of the infection. How HDV could evolve and why HBV was selected as a helper virus remains unknown. Since the discovery of Na+-taurocholate co-transporting polypeptide as the essential uptake receptor for HBV and HDV, we are beginning to understand the interactions of HDV and the immune system. While HBV is mostly regarded a stealth virus, that escapes innate immune recognition, HBV-HDV coinfection is characterized by a strong innate immune response. Cytoplasmic RNA sensor melanoma differentiation antigen 5 has been reported to recognize HDV RNA replication and activate innate immunity. Innate immunity, however, seems not to impair HDV replication while it inhibits HBV. In this review, we describe what is known up-to-date about the interplay between HBV as a helper and HDV's immune evasion strategy and identify where additional research is required.     

The Proportion of Vδ1T Cells in Peripheral Blood Correlated with Prognosis of Sepsis

Background: Sepsis is a serious condition with a high mortality rate, and septic patients often have organ dysfunction, low tissue perfusion and hypoxia, lactic acidosis, oliguria, or functional brain changes.Objective: To observe the number and the function of Vδ1T cells in peripheral blood of septic patients, to analyze the clinical significance of detecting Vδ1T cells, and to clarify the correlation of their presence with the prognosis of sepsis.Methods: The basic data of the septic patients were recorded at admission. The immunosuppressive function–related molecules on the surface of Vδ1T cells were detected, and the immunosuppressive function of Vδ1T cells was also evaluated.Results: Compared with the healthy controls, the proportion of Vδ1T cells in the blood of septic patients significantly decreased (P<0.01). The proportion of Vδ1T cells in septic patients correlated with the patients’ condition (P<0.05). The expression of glucocorticoid-induced tumor necrosis factor receptor (GITR), cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), and T-cell immunoglobulin and mucin domain-containing protein 3 (TIM-3) on the surface of Vδ1T cells in the blood of septic patients significantly increased (P<0.01). The increase of Vδ1T cells in septic patients had inhibitory effects on T cell proliferation and interferon (IFN)-γ secretion. These findings implied that the immunosuppression of Vδ1Tcells in the peripheral blood of septic patients was significantly higher than that of the healthy controls (P<0.01).Conclusion: Changes in Vδ1T cells in septic patients were closely related to the patient’s condition and prognosis.     

抗γ-氨基丁酸B型受体脑炎五例分析

目的:探讨抗γ-氨基丁酸B型受体(GABA BR)脑炎患者的临床特点、治疗及预后。方法:回顾性总结2017年9月至2019年6月香港大学深圳医院神经内科诊治的5例抗GABA BR脑炎病例,分析其临床资料、辅助检查、治疗经过,随访3.5~23.0个月并评估预后。结果:5例抗GABA BR脑炎患者(19~81岁)均急性起病,以难治性癫痫为主要临床表现,其中4例颅脑磁共振成像显示颞叶及海马为主的T 2/液体衰减反转恢复序列高信号。脑电图均提示慢波或癫痫样放电。4例肺部发现占位,病理均确诊为小细胞肺癌。5例接受一线免疫抑制治疗(激素联合丙种球蛋白或血浆置换)效果均欠佳,3例接受了二线免疫治疗(利妥昔单抗、环磷酰胺),其中2例合并肿瘤者同时接受了肿瘤治疗,接受二线治疗及肿瘤治疗的患者疗效明显好于单纯一线治疗者。结论:抗GABA BR脑炎主要表现为以难治性癫痫为特征的边缘性脑炎综合征。一线治疗效果欠佳的抗GABA BR脑炎尽快启动二线治疗可明显改善预后。