Association of plasma viremia with HIV-1 RNA levels in cervicovaginal lavage secretions in HIV-1 seropositive ART naïve women from Pune,India

BackgroundCoherent drug/microbicide/vaccine development research would benefit through a precise knowledge of HIV dissemination and its persistence in the female genital tract. Understanding relationship between plasma viremia and cervicovaginal HIV shedding may help to unveil mechanisms underlying transmission, compartmentalization and pathogenesis.ObjectivesTo study the association between HIV-1 RNA levels in the plasma and CVL specimens.Study designWhole blood, plasma and CVL specimens were collected from 36 ART naïve HIV-1 seropositive women qualifying the study inclusion criteria. Absolute CD4 counts, plasma and CVL HIV-1 RNA levels were estimated using commercially available kits (BD MultiSET™ Kit, Becton Dickinson, US and Abbott RT, Abbott Molecular, Germany). Correlation between plasma and CVL viral load was estimated by the Spearman's rank correlation coefficient. Additionally, the correlation between CVL viral load and absolute CD4 counts was studied.ResultsHIV-1 viral load in the CVL specimens was successfully quantified using the Abbott RT. Twenty-seven of 36 women (75%) had detectable HIV-1 RNA levels in plasma and CVL specimens. The CVL viral load did not show any correlation with plasma viral load (ρ = 0.281, p = 0.096) and showed a ‘moderate correlation’ (ρ = −0.563, p = 0.0004) with absolute CD4 counts.ConclusionsAlbeit, the Abbott RT is designed for estimating plasma HIV-1 RNA levels, the study reports its use for estimating HIV-1 RNA levels in the CVL specimens as well. In accordance with the previous studies, our results suggest that plasma and CVL viral load are not correlated and plasma viremia might not solely predict cervico vaginal HIV shedding.     

Quantification and characterisation of IgG binding to mould spores by flow cytometry and scanning electron microscopy

The concentration of mould-specific IgG antibodies in serum may objectively indicate mould exposure and can help identifying exposed individuals. Although inhaled spores probably are the most important source of mould exposure, the commonly used methods for detecting mould-specific IgG antibodies are based on extracts from all mould components, with only low contribution from spores. We have developed a flow cytometric method using surface antigens on mould spores for quantifying mould-specific IgG antibodies in serum. Flow cytometric results were evaluated by comparison with ImmunoCap and ELISA measurements. The flow cytometric assay showed a broad linear dose-dependency and correlated moderately to strongly (r=0.41-0.97) with ImmunoCap and ELISA measurements. The IgG antibody binding was studied in detail by immunolabelling in scanning electron microscopy (SEM), revealing that morphology and IgG antibody binding differed among spores, both within and between mould strains. Germination studies by flow cytometry and SEM showed that IgG antibody binding to mould spores was altered during germination due to loss of coat. The present spore based antibody assay are simple and suitable for quantification of mould-specific IgG antibodies in serum, and includes specificity to other and possibly more relevant antigens than existing methods.     

虎眼万年青多糖对小鼠免疫功能的调节作用

目的 :依据虎眼万年青组分中多糖对小鼠巨噬细胞吞噬功能的影响 ,筛选并优化出 6 0 %醇浓度中性多糖活性组分S3,进而研究其对体液免疫、细胞免疫及细胞因子变化的影响 ,并从细胞和分子水平探讨其作用的机理。方法 :采用溶血素测定方法 ,测定S3对小鼠脾细胞溶血素抗体的诱导作用 ;采用3H TdR渗入法 ,测定S3对ConA诱导小鼠脾淋巴细胞的增殖作用 ;采用3H TdR后标记法 ,测定S3对NK细胞细胞毒活性的影响 ;以ELISA法测定S3对小鼠脾细胞IL 2产生的影响 ;利用流式细胞术 ,检测S3对T淋巴细胞亚群CD3、CD4、CD8、CD4 CD8阳性细胞百分率的影响 ;采用RT PCR方法检测IL 2mRNA的表达水平。结果 :S3高、中剂量组能明显增强小鼠脾细胞溶血素抗体的形成 (P <0 0 5 ) ;各剂量组均能明显增强ConA诱导的淋巴细胞增殖能力 (P <0 0 0 1) ;各剂量组均能增强NK细胞的细胞毒活性并促进IL 2的产生 (P <0 0 0 1,P <0 0 1) ;高、中剂量组CD8阳性细胞百分率明显降低 (P <0 0 0 1) ,各剂量组均能显著地提高CD4 CD8阳性细胞百分率 (P <0 0 0 1) ;高剂量组可明显促进脾细胞中细胞因子IL 2的mRNA表达 ,使表达量增加 (P <0 0 5 )。结论 :S3具有较强的增强机体多种免疫功能的作用 ,可利用开发为一种免疫增强药物。     

T细胞受体库及细胞因子表达与胃癌进展及转移的关系

目的　了解在胃癌的发展过程中 ,肿瘤细胞与机体免疫系统间相互作用的特征。方法采用高敏感的放射性标记半定量RT PCR技术检测胃癌病人癌组织、非癌性粘膜组织及外周血各细胞亚群中细胞因子及T细胞受体亚家族mRNA的表达。结果　进展期胃癌外周血CD8+ T细胞中的增殖性T细胞克隆数低于早期胃癌 (P =0 .0 5 )。有淋巴结转移病例外周血CD8+ T细胞和CD4 + T细胞中的增殖性T细胞克隆数较无转移组明显减少 (P =0 .0 0 0 17、P =0 .0 16 )。有淋巴结转移病例的癌组织 ,其CD8+ T细胞中IL 6、IL 8、TNF α和CD4 + T细胞中IL 4mRNA的水平 (0 .4 3± 0 .17、0 .4 2± 0 .11、0 .18± 0 .0 5、0 .0 8± 0 .0 3)均较非癌性粘膜组织中的 (0 .0 8± 0 .0 2、0 .17± 0 .0 5、0 .0 8± 0 .0 3、0 .0 1± 0 .0 0 )增高 (P =0 .0 4 0、P =0 .0 2 0、P =0 .0 17、P =0 .0 34) ;而无淋巴结转移病例的癌组织与非癌性粘膜组织中各细胞因子的表达均未发现统计学差异。结论　胃癌病人T细胞受体库及细胞因子表达与胃癌进展及转移相关 ,进展期胃癌及发生转移的病例免疫系统受到抑制。     

应用长链RT-PCR法扩增我国登革2、4型病毒株全长cDNA

目的：采用长链RT-PCR技术扩增登革2型及4型病毒基因组全长cDNA，为构建登革病毒全长cDNA克隆、表达，深入阐明致病机理及探索新型疫苗奠定基础。方法：根据已测定的登革2、4型病毒全基因组序列，设计上下游引物。从感染登革病毒的乳鼠脑中提取病毒基因组RNA，采用长链RT-PCR技术进行扩增。为检验扩增产物的特异性，以PCR产物为模板扩增覆盖基因组的10个片段。将含有复杂二级结构的5′非编码区扩增片段，在377A型自动测序仪进行序列分析。结果：扩增出登革2、4型病毒基因组全长近11kb cDNA分子，非编码区测序结果表明扩增产物为登革2、4型病毒所特有。结论：利用长链RT-PCR首次成功扩增出登革病毒全长cDNA分子。