Significance of serum IgA in patients with acute hepatitis E virus infection

AIM: To study the significance of serum anti-hepatitis E virus (HEV) IgA in patients with hepatitis E. METHODS: A new method was established to assay anti-HEV IgA, which could be detected in the middle phase of the infection. We compared anti-HEV IgA assay with anti-HEV IgM and anti-HEV IgG assay in sera from 60 patients with positive HEV-RNA. RESULTS: The 60 patients with positive HEV-RNA had both anti-HEV IgA and anti-HEV IgM and 410 patients with negative HEV-RNA were used as control. Periodic serum samples obtained from 60 patients with hepatitis E were tested for HEV RNA, anti-HEV IgM, anti-HEV IgA and anti-HEV IgG. Their HEV-RNA was detectable in the serum until 20±11 d. We used anti-HEV IgM and anti-HEV IgA assay to detect HEV infection and positive results were found in 90±15 d and 120±23 d respectively, the positive rate of anti-HEV IgA was higher than that of anti-HEV IgM and HEV-RNA (P <0.05). CONCLUSION: The duration of anti-HEV IgA in serum is longer than that of anti-HEV IgM, and anti-HEV IgA assay is a good method to detect HEV infection.     

Der f2重组蛋白用于变应性鼻炎患者血清ELISA检测

目的：以重组表达的野生型粉尘螨变应原蛋白质第2组（Derf2）分作为固相包被抗原,建立间接酶联免疫吸附试验（ELISA）法,检测粉尘螨致敏的持续性变应性鼻炎患者血清中的特异性IgE浓度。方法：经过皮肤点刺试验证明的24例粉尘螨反应阳性血清和2例阴性血清作为IgE血清样本。以粉尘螨变应原蛋白质第2组分固相包被酶标板,辣根过氧化物酶（HRP）标记的抗人IgE单抗作为第2抗体组成测试系统分析特异性IgE。结果：间接ELISA系统检测灵敏度为0.73U.mL-1。在4.0U.mL-1、12.0U.mL-1、22.0U.mL-1浓度,批内重复性和批间重复性分别为9.5%,7%,6.1%和12.8%,9.1%,7.2%。24例皮试阳性患者血清经ELISA分析,有22例阳性。结论：以粉尘螨变应原蛋白质第2组分作为固相包被抗原的间接ELISA法可用来对患者血清sIgE作定量或定性分析,有助于持续性变应性鼻炎的实验诊断。     

ELISA检测特异性IgG4诊断肺吸虫病的效果观察

目的探讨用酶联免疫吸附试验(ELISA)检测特异性IgG4诊断肺吸虫病的效果.方法采用ELISA法检测了肺吸虫病病人血清中的特异性IgG和IgG4抗体及肝吸虫、囊虫、旋毛虫、日本血吸虫病病人和正常人血清中的交叉抗体.结果检测肺吸虫病病人血清中IgG4的敏感性为95.35%,检测正常人血清的特异性为100%,与常规使用的酶联葡萄球菌A蛋白(HRP-SPA)检测结果及检测IgG结果比较差异无显著性(P均＞0.05);与其他寄生虫病病人血清中的交叉反应率,IgG4显著低于用常规HRP-SPA检测结果. 结论ELISA法检测肺吸虫病病人血清中特异性IgG4具有较高的诊断应用价值.     

斑点金免疫渗滤法在检测囊虫抗体中的应用

目的　将斑点金免疫渗滤法用于检测囊虫抗体 ,以制备囊虫病诊断试剂盒。方法　经透析的猪囊尾蚴囊液作为检验抗原 ,对 71份囊虫病患者、90份正常人和 2 0份其他病患者血清进行了斑点金免疫渗滤法检测并与酶联免疫吸附法比较。结果　斑点金免疫渗滤法的敏感性为 90 .1% (6 4 / 71) ,特异性为 95 .6 % (86 / 90 ) ,其他病患者血清反应中仅 1例脑肿瘤患者血清阳性 ,其余为阴性。斑点金免疫渗滤法和酶联免疫吸附法的符合率为94 .4 % (15 2 / 16 1)。结论　斑点金免疫渗滤法有较好的应用于临床检测囊虫病的潜力     

三种类型肺癌患者外周血Th1/Th2相关细胞因子的临床分析

目的：了解不同病理类型肺癌患者辅助性T细胞亚群（Th1/Th2）的反应状态,探讨肺癌发生发展的免疫机制。方法：收集三种不同病理类型肺癌患者47例（鳞癌23例,腺癌15例,小细胞肺癌9例）、健康志愿者31例的血清,分成肺癌组、正常对照组,用酶联免疫吸附试验（ELISA）检测各组外周血中Th1型细胞因子、白细胞介素2（IL-2）、γ-干扰素（IFN-γ）和Th2型细胞因子IL-4、IL-10的浓度。结果：三种不同病理类型肺癌患者外周血中IL-2、IFN-γ浓度均显著低于正常人组,IL-4、IL-10浓度显著高于正常人组（P〈0.05）。结论：腺癌、鳞癌、小细胞非分化癌三种不同病理类型的肺癌患者外周血中的免疫细胞均呈现Th2型免疫反应优势状态,呈现Th1/Th2的漂移状态。     

大鼠股骨骨折合并脑外伤时HIF-1α及Cbfα1的血清表达及意义

目的探讨大鼠股骨骨折合并脑外伤时低氧诱导因子-1α(HIF-1α)及核心结合因子α1(Cbfα1)在血清中的表达及意义。方法选用70只3月龄健康SD大鼠,随机分为假手术组(A组),股骨骨折组(B组),脑外伤组(C组)和骨折合并脑外伤组(D组),分别进行造模。造模术后24 h取C、D组脑组织行苏木素-伊红染色判断脑外伤程度。1 d、3 d、1周、2周、3周、4周、5周通过酶联免疫吸附法(ELISA)检测各组HIF-1α及Cbfα1的血清表达。结果 B、C、D组内不同时间段HIF-1α及Cbfα1表达比较,差异有显著性(P0.05);同一时间段B、C、D组表达均明显高于A组,D组高于B、C两组,差异均有显著性(P0.05)。结论 HIF-1α及Cbfα1在大鼠骨折和脑外伤后均有较明显的表达,在骨折合并脑外伤后表达更加突出,这可能是造成脑外伤后加速骨折愈合的重要因素之一。     

Age-related antibody profiles in Schistosoma haematobium infections in a rural community in Zimbabwe

Antibody responses to soluble Schistosoma haematobium egg (SEA) and worm (SWA) antigens in a rural Zimbabwean study population were examined by ELISA. One hundred and sixteen S. haematobium infected and 124 non-infected individuals representing individuals greater than five years old, were included. Non-endemic control sera were obtained from a schistosomiasis non-endemic part of Zimbabwe and from Norwegian blood donors. A possible association between IgE antibody responses and resistance to S. haematobium infection was indicated by a negative correlation between IgE anti-SEA levels and intensity of S. haematobium infection, and by a positive correlation between IgE responses to SEA and SWA and age. Similarly, an association between IgA and anti-SWA and resistance to S. haematobium was suggested by a negative correlation to intensity of infection and a positive correlation with age. A probably association between IgM and IgG4 with susceptibility to S. haematobium infection was described; intensity of S. haematobium infection correlated positively with IgG, IgG4 and IgM responses to SEA and with IgG4 and IgM responses to SWA, also age correlated negatively with IgG4 and IgM responses to SEA and with IgG4 responses to SWA. These findings support the concept of IgG4 and IgM as blocking antibodies. Significant positive correlations between antibody responses to SEA and SWA suggests cross-reactivity between eggs and adult worms. In addition, the recognition by IgE and IgG4 of the same schistosomulum antigens in immunoblotting suggests competition for the same antigens.     

Assessing the validity of an ELISA test for the serological diagnosis of human fascioliasis in different epidemiological situations

Objectives To improve the diagnosis of human fascioliasis caused by Fasciola hepatica and Fasciola gigantica, we evaluated the diagnostic accuracy of an enzyme‐linked immunosorbent assay (ELISA), with Fasciola antigen from the adult liver fluke, for the detection of IgG against fascioliasis in human sera. Methods The sera of 54 fascioliasis cases, originating from three endemic areas, were used in this evaluation: (i) a hyperendemic F. hepatica area where humans usually shed a great number of parasite eggs in faeces (11 sera); (ii) an epidemic F. hepatica area where humans usually shed small amounts of parasite eggs (24 sera) and (iii) an overlap area of both Fasciola species and where human shedding of parasite eggs in faeces is usually scarce or non‐existent (19 sera). One hundred and sixty‐eight patients with other parasitic infections and 89 healthy controls were also analysed. Results The respective sensitivity and specificity of this assay were 95.3% (95% confidence intervals, 82.9–99.2%) and 95.7% (95% confidence intervals, 92.3–97.5%). No correlation between egg output and the OD450 values of the F. hepatica IgG ELISA test was observed. Conclusions This test could be used both as an individual serodiagnostic test for human fascioliasis when backed up by a compatible clinical history together with a second diagnostic technique for other cross‐reactive helminth infections, and in large‐scale epidemiological studies of human fascioliasis worldwide.     

Frequency of antibodies to Toxocara in Cuban schoolchildren

Objective The aim of the study was to determine the frequency of antibodies to Toxocara in Cuban schoolchildren. Methods The frequency of antibodies to Toxocara canis was assessed with a commercial enzyme‐linked immunosorbent assays kit in school‐aged children from two municipalities of Cuba. Univariate analysis and a multivariable logistic regression analysis adjusted for age, sex, municipality and co‐infection with helminth and/or protozoa were conducted. Results The percentage of children with antibodies to Toxocara was 38.8% (392/1011; 95% CI = 36.8–42.8). Antibody positivity was significantly associated with gender and co‐infections with intestinal parasites, but not with age or municipality. Conclusion Cuban children are highly exposed to the Toxocara parasite, corresponding well with reported environmental contamination with Toxocara parasite eggs and T. canis prevalences in dogs in Cuba. Relevant policy makers and the Cuban population need to be better informed about this preventable infection.