维生素K对HBsAg与抗HBS结合的抑制作用

在ＲＰＨＩ试验中，将ＶｉｔＫ１或ＶｉｔＫ３预先与ＨＢｓＡｇ阳性血清作用后，再加抗ＨＢｓ单克隆抗体诊断红细胞，可见红细胞呈圆点状沉淀，提示ＨＢＳＡｇ与抗ＨＢｓ的结合受到抑制，该抑制作用呈浓度依赖性．ＲＰＨＩ试验后的抗ＨＢｓ单克隆抗体诊断红细胞，经洗涤后再与ＨＢｓＡｇ阳性血清作用，仍出现明显凝集，表明ＶｉｔＫ对ＨＢｓＡｇ与抗ＨＢｓ结合的抑制作用不是通过影响抗ＨＢｓ而产生的。     

食品及公共场所从业人员HBsAg阳性结果分析

为了解我县食品及公共场所从业人员HBsAg携带者分布状况 ,探索有效的控制措施 ,笔者对晴隆县 2 0 0 2年度 13 0 8名食品及公共场所从业人员HBsAg阳性结果进行分析 ,现报道如下。1　资料来源与方法1 1　资料来源　晴隆县 2 0 0 2年度食品及公共场所从业人员健康体检资料。1 2　方法　HBsAg检测采用上海实业科华生物技术有限公司生产的改良型冻干乙型肝炎表面抗原诊断血球。2　结果2 1　不同年龄HBsAg阳性率　受检者 13 0 8人 ,HBsAg阳性 3 6人 ,阳性率为 2 75 % ,其中阳性率最低为 3 0～ 3 4岁组 ,阳性率为0 46% ;最高为 45～ 49岁…     

德州市高中新生HBsAg携带情况调查

乙型肝炎是当前严重危害人类健康的传染病,而我国又是乙肝病毒感染的高发区,为了解我市高中新生的乙肝病毒感染     

乙型肝炎表面抗原“免疫逃避”突变体在哺乳动物细胞中的表达

利用乙型肝炎病毒ＤＮＡ开放框架上的ＢａｍＨＩ和ＨｐａＩ位点，酶切消化质粒载体ＰＥｃｏｂ６（含双拷贝ＨＢＶＤＮＡ），得到约９００ｂｐ的ＨＢＶ－Ｓ基因片断。将其插入到噬菌粒载体ＰＢｌｕｅｓｃｒｉｐｔｓｋ＋的ＳｍａＩ位点上。然后通过体外寡核苷酸介导的人工定点突变获得一系列（共１２种）Ｓ基因“免疫逃避”突变型。再通过ＥＢ病毒真核表达载体ｐＭＥＰ４上的ＢａｍＨＩ和Ｋｐｎｌ位点将噬菌粒ｐＢｌｕｅｓｃｒｉｐｓｋ＋上的Ｓ基因突变型片断定向克隆到ＰＭＥＰ４上，从而构建了含乙肝Ｓ基因突变型的重组质粒ｐＭＥＰ４ＨＢＳＭ。用其转染人肝癌传代细胞系ＨｅｐＧ２，经潮霉素选择，三周后获得抗性细胞克隆。经用抗ＨＢｓ单克隆抗体（含针对ＨＢｓＡｇ“ａ”抗原决定簇）检测除含变异体１４５（即１４５位上甘氨酸为精氨酸替代）外其余抗变异体ＨＢｓＡｇ均为阳性。经Ｗｅｓｔｅｒｎｂｌｏｔ证实变异体１４５，在分子量约为２３ＫＤ处有一特异ＨＢｓＡｇ蛋白带。     

2000～2006年汝城县不同人群乙肝病毒感染情况

目的了解汝城县不同人群乙肝病毒感染的变化情况。方法用ELISA法测定近年来我县不同人群HB-sAg携带情况。结果成人组为14.1%-15.5%,孕妇组为8.8%-13.6%,儿童组为4.0%-8.6%。结论预防及控制乙型肝炎的形势仍十分严峻 应加强卫生院宣教,进行主动免疫及防止母婴传播等措施。     

青果微量元素的测定及其含量与功效的关系

用电感耦合等离子体发射光谱法(ICP—AES),同时测定了广州与潮州产青果中13种微量元素和宏量元素的含量,结果发现其含有多种人体必需和与乙型肝炎的发生发展有关的微量元素;初步讨论了它们与青果功效的关系。     

Localization of hepatitis B surface antigen epitopes present on variants and specifically recognised by anti-hepatitis B surface antigen monoclonal antibodies

Small hepatitis B surface antigen (HBsAg) is considered to be the best marker for the diagnosis of Hepatitis B virus infection. However, HBsAg variants with mutations within the "a" determinant may be poorly or not detected by diagnostic assays. Three anti-HBsAg monoclonal antibodies (6H6B6, 27E7F10, and 2G2G10), directed against conformational epitopes, were tested for their ability to detect the wild-type HBsAg as well as variant forms and their respective epitopes were localised on the HBsAg sequence by using the phage-displayed peptide library technology. Whereas 6H6B6 did not detect mutations T123N, S143L, D144A and G145R, 27E7F10 binding was affected by mutations P120T and G145R. In contrast, 2G2G10 reacted strongly with all tested variants including variant with the G145R mutation. Part of the 6H6B6 epitope was located in the major hydrophilic region (MHR) at residues 101-105, the 27E7F10 epitope (residues 214-219) was located near the C-terminal end of the antigen and the 2G2G10 epitope at residues 199-208, within the theoretical fourth transmembrane helix. The 2G2G10 epitope localisation brings information about the HBsAg structure and the validity of established topological models. Finally, 2G2G10 is a valuable tool for HBsAg variant detection that is used as capture phase in a new bioMérieux diagnostic assay, which is currently in development.     

Genotypes and S-gene variability of Mexican hepatitis B virus strains

The genotypes and subtypes of 15 Mexican hepatitis B virus strains were determined by sequencing and phylogenetic analysis of the small S-gene. The most predominant strains were found to be divergent genotype/subtype F/adw4 strains (66.6%), followed by A/adw2 (20.0%), D/ayw3 (6.7%), and G/adw2 (6.7%). The S-genes of the Mexican genotype F strains and two Nicaraguan strains described previously formed a subcluster with more than 4% divergence from the other strains within this genotype. The Mexican strains within genotypes A and D showed the highest homology with strains from Europe and the United States. Ten amino acid substitutions not described previously were found in the S-genes of strains from nine chronic carriers, whereas the S gene in strains from six acute hepatitis B patients were highly conserved as compared to their respective genotypes. One genotype F strain from an HBsAg positive chronic carrier had a T to A mutation at position 647, forming a translational stop at codon 216. Two genotype F strains from HBsAg negative chronic carriers had a Val180 instead of an Ala found in the other genotype F strains. This study shows that a divergent genotype F predominates in Mexican strains analyzed, which presented amino acid substitutions not reported previously outside the a determinant.     

Detection of hepatitis B surface antigen (HBsAg) in peripheral blood mononuclear cells of patients with acute and chronic active hepatitis B

Seventy five patients with acute and chronic active hepatitis (CAH) were studied by indirect immunofluorescence with monoclonal antibodies for the presence of hepatitis B surface antigen (HBsAg) on peripheral blood mononuclear cells (PBMC). The viral surface antigen was detected in the PBMC of all the patients with hepatitis B virus (HBV)-induced CAH and in acute patients with more than 2 months of evolution. No HBsAg was detected in the samples obtained from 12 normal controls or from 14 non-A, non-B CAH patients. Analysis of PBMC subsets revealed that HBsAg was present in non-T cells; dual fluorescence studies showed HBsAg on surface Ig-positive lymphocytes. The binding of anti-HBs monoclonal antibodies was higher than that of a goat anti-HBs serum, and the highest reactivity was observed with an antibody against the pre-S(2)-region sequence. Both HBsAg and hepatitis B core antigen (HBcAg) were also detected in lysates of PBMC by dot blot analysis.