Serum IgG antibodies to human herpesvirus-6 (HHV-6) do not predict the progression of HIV disease to AIDS

Objectives: To evaluate if different levels of human herpesvirus 6 (HHV-6) antibodies can predict HIV disease progression. Design: Longitudinal study of individuals with a documented date of HIV seroconversion. Setting: Clinical centers located throughout Italy. Patients: Individuals who serconverted for HIV between 1983 and 1995 in Italy. Methods: Sera were tested for IgG antibodies to HHV-6 using a commercial enzyme immunoassay. A serum sample with an optical density (OD) 242 (i.e. the mean value of 10 negative controls+ 4×standard deviation) was considered as HHV-6 positive; the progression of HIV disease was evaluated estimating the relative hazards (RH) of AIDS (by Cox models) for individuals with higher levels vs. lower levels of HHV-6 antibodies or considering levels of antibodies based on 10% increase of the distribution (deciles). Rates of CD4 decline fitting linear regression were also estimated. Results: A total of 381 persons were followed for a median time of 4 years (range: 0.15–9 years) following the date of collection of the serum sample. The median OD value of HHV-6 antibodies was 306, with an interquartile range of 241–440 and a range of 48–2330. A slight inverse correlation was found between HHV-6 antibody levels and age of the individual at the time of serum collection (Spearman rank correlation coefficient, –0.16; p = 0.0013). No association was found between HHV-6 and CD4 level or between HHV-6 and CD8 level at the date of serum collection. The unadjusted RH of progression to AIDS was 0.63 (95% CI: 0.42–0.96) for HHV-6 positive individuals vs. HHV-6 negative; when adjusting for possible confounders (CD4, age, pre-AIDS HIV-related pathologies at the date of sera collection, and previous anti-herpes treatment), the RH of AIDS increased to 0.80 (95% CI: 0.51–1.23). No particular association with HIV disease progression was found when using the deciles of the distribution of HHV-6 antibodies. The median CD4 cell loss was 5.0 × 106 cells/l per month among HHV-6 positive individuals and 5.7 × 106 cells/l per month among the others. Conclusions: The presence of high levels of HHV-6 antibodies does not seem to predict the clinical or immunologic progression of HIV disease.     

HIV-1急性感染

HIV-1是目前AIDS流行的主要病原体.疑诊HIV-1急性感染,用定量HIV-1 RNA或p24抗原检测可缩短诊断时间.一旦确诊,应考虑早期采用以免疫为基础的联合治疗.     

Seroepidemiological correlations of antibodies to human herpesviruses and human immunodeficiency virus type 1 in African patients

A seroepidemiological evaluation of the humoral immune response against human herpes viruses was carried out in patients with and without HIV infection in Tanzania to study the role of these viruses as a cofactor in AIDS. Serum specimens were obtained from 321 outpatients and 100 healthy schoolchildren of a rural population in the Kagera Region, Tanzania, and from 149 inpatients of an urban population in Dar-es-Salaam, Tanzania. The data were analysed by logistic models taking into account demographic variables. The data obtained revealed no differences in the prevalence of antibodies to human herpes viruses between the different groups. Therefore, our study under the present conditions and the observed stages of AIDS does not suggest an influence of HIV infection on human herpesvirus infection or serologic response.Corresponding author.     

Detection of antibodies to human immunodeficiency virus type I by using synthetic peptides and time-resolved fluoroimmunoassay (TR-FIA)

A simple, rapid, reproducible and sensitive peptide-Time-Resolved-Fluoroimmunoassay (TR-FIA) method is described which allows the detection of antibodies to the Human Immunodeficiency Virus type 1 (HIV-1). By using a panel of synthetic peptide antigens that covered env, gag and pol amino acid sequences, a 20 amino acid peptide (GIWGCSGKLICTTAVPWNAS) describing an immunodominant and conserved domain on the gp41 region of the BH10 clone was found to be the most reactive in this study. Optimal conditions for antigen concentration, serum dilution and incubation time were established. The peptide-TR-FIA is specific, as assessed by testing HIV-1 positive sera which included samples from AIDS, ARC patients and HIV-positive drug users. The test was used to detect HIV antibodies in 250 well characterized HIV-1 positive sera and 50 normal sera. Peptide-TR-FIA results indicate that the env peptide was highly reactive with HIV-positive sera showing a sensitivity of 100%. None of the 50 control sera showed positive reactivity against the synthetic peptide.Furthermore the peptide-TR-FIA allowed a fine titration of antibodies to defined epitopes of immunodominant HIV structural proteins that usually cannot be achieved by peptide-ELISA assays.     

人免疫缺陷病毒1型潜伏感染激活剂研究现状

高效抗逆转录病毒治疗(HAART)对控制HIV-1进展效果显著,但病毒潜伏库的存在导致病毒无法完全清除.HIV-1感染后,潜伏库建立早,半衰期长,长期处于静息状态,是根治HIV-1感染的主要障碍之一.目前清除病毒潜伏库的方法有潜伏感染激活剂、免疫治疗和基因治疗等.此文主要讨论了HIV-1潜伏感染激活剂相关内容.     

西安市男男性行为人群感染HIV-1的分子流行病学研究

目的 了解西安市MSM感染HIV-1毒株亚型分布。方法 采集2010--2012年西安市确证的经男男同性传播的HIV感染者外周静脉血5ml,抗凝后分离血浆,提取总RNA,利用巢式反转录PCR扩增HIulgag和env基因,利用Mega5.2软件与国际参考序列进行拼接、比对、计算基因离散率和构建系统进化树;同时进行流行病学问卷调查,行为学调查重点包括性行为特征、吸毒史、献血史等。结果 168份样本中,165例gag与env序列分型结果 一致,分别为79例(47.0%)CRF01AE、74例(44.o%)CRF07BC、12例(7.1%)B亚型。3例gag与env序列分型结果不一致,分别为2例(1.2%)CRF01AE/A1、1例(0.6%)CRF07BC/CRF01AE。结论 西安市MSM感染HIV-1毒株亚型主要为CRF01AE、CRF07BC。     

HIV-1B′亚型毒株新型耐药相关突变位点的筛选

目的 筛选HIV-1 B′亚型病毒株中可能存在的新型耐药相关突变位点.方法 收集整理前期研究获得的451条HIV-1B′亚型pol区基因序列,序列含蛋白酶全长(1～99个密码子)和反转录酶全长(1～560个密码子),长度约1977 bp.将354条来自接受抗病毒治疗艾滋病患者的(服药组)序列与97条来自未接受治疗患者的(未服药组)序列,分别与B亚型野生型pol基因共享序列进行逐个密码子比对,筛选在服药组序列中出现的频率显著高于未服药组序列的突变位点,将筛选出来的突变位点在斯坦福大学HIV-1耐药数据库中检索,根据数据库收录的情况及解释,初步分析突变与耐药的关系.结果 在服药组序列中反转录酶区有6个位点7个突变的频率显著高于未服药组,分别是D123E、V292I、K366R、T369A、T369V、A371V和1375V,即前2个突变位于反转录酶的聚合酶区、后5个突变位于反转录酶的连接区.检索数据库收录情况,有7个突变均为相应位点的主要变异形式,在服药患者中出现的频率显著高于未服药患者.结论 筛选出的HIV-1 B′亚型病毒株7个突变可能与耐药有关.     

HIV-1B′亚型毒株新型耐药相关突变位点的筛选

目的 筛选HIV-1 B′亚型病毒株中可能存在的新型耐药相关突变位点.方法 收集整理前期研究获得的451条HIV-1B′亚型pol区基因序列,序列含蛋白酶全长(1～99个密码子)和反转录酶全长(1～560个密码子),长度约1977 bp.将354条来自接受抗病毒治疗艾滋病患者的(服药组)序列与97条来自未接受治疗患者的(未服药组)序列,分别与B亚型野生型pol基因共享序列进行逐个密码子比对,筛选在服药组序列中出现的频率显著高于未服药组序列的突变位点,将筛选出来的突变位点在斯坦福大学HIV-1耐药数据库中检索,根据数据库收录的情况及解释,初步分析突变与耐药的关系.结果 在服药组序列中反转录酶区有6个位点7个突变的频率显著高于未服药组,分别是D123E、V292I、K366R、T369A、T369V、A371V和1375V,即前2个突变位于反转录酶的聚合酶区、后5个突变位于反转录酶的连接区.检索数据库收录情况,有7个突变均为相应位点的主要变异形式,在服药患者中出现的频率显著高于未服药患者.结论 筛选出的HIV-1 B′亚型病毒株7个突变可能与耐药有关.     

Selective pressures of human immunodeficiency virus type 1 (HIV-1) during pediatric infection

Pediatric HIV-1 infection presents remarkable features that are distinct from those observed in adult infection. In vertically HIV-1-infected children, the viral load declines more slowly, and the cytotoxic T-lymphocyte response emerges late, only after the sixth month of life. This response generally tends to be narrow and less intense than that seen in adults. While the nuances of immune response at the cellular level during pediatric HIV-1 infection have been addressed, there is a lack of studies focusing on the consequences of this delayed and narrowed immune response at the population level. To better explore these features, we evaluated the selection regimen in gag, pol and env gene fragments of HIV-1 during pediatric infection. We estimated the number of nonsynonymous substitutions (d(N)) and synonymous substitutions (d(S)) codon-by-codon, using the maximum likelihood method and a modified counting method. Notably, both methods indicated a similar intensity of selection (measure by mean d(N)/d(S) ratio) between children and adults. Additionally, sites under positive selection were equally distributed along HIV genes and the location of these sites was analogous between children and adults. Therefore, the selective regimen in HIV during pediatric infection is equally broad and intense likewise the observed in adults. Unexpectedly, our phylogenetic-based analysis enabled us to identify two regions in the env gene of HIV with distinct adaptive functions. The first region, located in the vicinity of V3 loop, contains sites that might increase viral fitness within-host during antibody attack and virus-cell interaction. The second region, restricted to amino acids 334-368 of Gp160, contains sites that might increase viral fitness during interhost transmission at the population level.     

Vaccine-induced protection from infection of mice by chimeric human immunodeficiency virus type 1, EcoHIV/NL4-3

EcoHIV/NL4-3 is a chimeric human immunodeficiency virus type 1 (HIV-1) that can productively infect mice. This study tests the utility of EcoHIV/NL4-3 infection to reveal protective immune responses to an HIV-1 vaccine. Immunocompetent mice were first immunized with VRC 4306 which encodes subtype B consensus sequences of gag, pol, and nef and then were infected by EcoHIV/NL4-3. Anti-Gag antibodies were sampled during immunization and infection. The extent of EcoHIV/NL4-3 infection in spleen cells and peritoneal macrophages was determined by quantitative real-time PCR (QPCR).

Although antibody titres were not significantly different in control and vaccinated groups, VRC 4306 immunization induced protective responses that significantly reduced virus burden in both lymphocyte and macrophage compartments. These results indicate that EcoHIV/NL4-3 infection can be controlled by HIV-1 vaccine-induced responses, introducing a small animal model to test vaccine efficacy against HIV-1 infection.     

Improved immunoblotting for the detection and quantitative analysis of antibodies to human immunodeficiency virus

Detection of antibodies to single HIV-1 proteins was performed by modified Western-blotting procedure. The use of [35S]-Streptavidin instead of Avidin-peroxidase conjugate greatly enhances the sensitivity of the method and enables useful quantitative analysis of results.Corresponding author.     

Molecular subtypes ofenv sequences around V3 region of human immunodeficiency virus type 1 in Taiwan

Samples of peripheral blood mononuclear cells (PBMC) were collected during 1990–91 from seropositive healthy, male HIV-1 carriers visiting Taipei Venereal Disease Control Center, and a male AIDS patient admitted to a general hospital. The V3 and its flanking nucleotide (nt) sequences in their DNA were amplified by polymerase chain reaction (PCR) and compared with those of known HIV-1 prototypes. The nt sequences obtained from 21 individuals (e.g., TW92) clustered as Group A, which were highly homologous (95.6–99.5%) to that of HXB2 virus while those from 6 individuals (TW90, TW91, TW97, TW99, TW102 and TW104) were classified as Group B showing low similarities (73.2–84.2%) to those of HXB2 and moderate similarities (80.7–90.0%) to those of SC and Bangkok (BK) viruses. By comparison of their deduced amino acid sequences with those of consensus sequences for subtypes A-F as defined by Myers et al. (1993), both Groups A and B viruses (except TW102) together with those of HXB2, SC and BK viruses could be identified as members or variants of subtype B, and the TW102 virus as a member of subtype E viruses. Individuals with the Group A viruses included 4 homosexual and 17 heterosexual Taiwanese males, 2 of the latter having a history of I.V. drug abuse. Among individuals with Group B viruses, those with TW97, TW99, TW104 and TW91, who was an AIDS patient, were heterosexual Taiwanese males, whereas both TW90 and TW102 viruses were from individuals who were overseas heterosexual Chinese from Thailand, the former with a history of I.V. drug abuse and the latter without.     

艾滋病病毒1型与乙型肝炎病毒X蛋白的相关性

最近研究显示,HIV和HBV具有部分相同生物活性,在艾滋病病程中相互协同作用。文中对HIV_1和HBx及其编码产物特点、相互作用及作用机制进行综述。     

Epidemiology of human T-lymphotropic virus type II (HTLV-II) infection in Spain

The human T-lymphotropic virus type II (HTLV-II) has recently been associated with the genesis of some subacute neurological syndromes and, rarely, with atypical T-lymphoid malignancies. The virus is endemic in some Amerindian and African tribes, and among intravenous drug users (IDUs) in North America and Europe. Given that HTLV-II is transmitted by the same routes as other human retroviruses, the screening of antibodies to HTLV-II in blood donors has became a matter of controversy in some countries. Herein, we describe the clinical, epidemiological and virological features of 113 individuals with HTLV-II infection identified in Spain up to September 1995. Most of them (94/113; 83%) were male, and all but seven were natives. Four were African immigrants living in Madrid and 3 had been born in other European countries. All but six subjects were IDUs, and sexual transmission of HTLV-II and transfusion were involved in five and one individual, respectively. Eighty-four percent of the IDUs infected with HTLV-II were co-infected by HIV-1 (93/107). Clinical manifestations potentially linked to HTLV-II were absent, although an IDU male co-infected by HIV-1 and HTLV-II developed a severe non-inflammatory proximal myopathy. In conclusion, HTLV-II infection is present in Spain, mainly among IDUs, with a growing incidence and a current overall prevalence of 2.0 percent.The members of the HTLV Spanish Study Group are listed in the Appendix.     

Effects of chronic alcohol drinking on receptor-binding, internalization, and degradation of human immunodeficiency virus 1 envelope protein gp120 in hepatocytes.

Although alcohol drinking increases susceptibility to human immunodeficiency virus (HIV) infection, possible mechanisms underlying the effects of alcohol are not yet known. Since the HIV envelope protein gp120 plays a key role in progression of HIV infection, the aim of the present study was to evaluate the toxicity and degradation of gp120 in hepatocytes isolated from liver of alcohol-preferring rats drinking either 15% ethanol in water or pure water for 70 days. The hypothesis was that alcohol drinking augmented the toxicity, but suppressed degradation of gp120. Hepatocytes from water-drinking rats (C-cells) or ethanol-drinking rats (Et-cells) were treated with laptacystin, anti-CD4 antibodies, CCR5 antagonist, or mannose, followed by [(125)I]gp120 or native gp120. At predetermined intervals, control (C) and ethanol exposed (Et) cells were analyzed for toxicity and degradation of gp120. In C-cells, [(125)I]gp120 binding and internalization peaked within 5-45 min and remained elevated for up to 10h and then decreased gradually. In Et-cells, [(125)I]gp120 binding peaked comparably to C-cells, but the binding remained to the peak level throughout the experimental period. C-cells exhibited the lysosomal/ubiquitin-mediated degradation of intracellular gp120, resulting in released gp120 fragments into the incubation medium that suppressed gp120-CD4 binding, improved cell viability, and inhibited gp120-induced apoptosis. Ethanol drinking suppressed gp120 degradation in and release of gp120 fragments from hepatocytes. The incubation medium of Et-cells did not suppress gp120-CD4 binding or the gp120-mediated apoptosis in hepatocytes. Thus, chronic alcohol drinking augmented the adverse effects of gp120 possibly by suppressing its degradation in hepatocytes. The present observation also suggests that a number of CCR5 or ubiquitin-based therapeutic drugs may not be effective in suppressing HIV infection in alcohol-drinking subjects.     

PedVacc 002: A phase I/II randomized clinical trial of MVA.HIVA vaccine administered to infants born to human immunodeficiency virus type 1-positive mothers in Nairobi

Background

A safe, effective vaccine for breastfeeding infants born to HIV-1-positive mothers could complement antiretroviral therapy (ART) for prevention of mother-to-child transmission of HIV-1. To date, only a few HIV-1 vaccine candidates have been tested in infants.

Trial design

A phase I/II randomized controlled trial PedVacc 002 was conducted to determine the safety and immunogenicity of a single, low dose of MVA.HIVA vaccine delivered intramuscularly to healthy 20-week-old infants born to HIV-1-positive mothers in Nairobi, Kenya.

Methods

Pregnant HIV-1-positive women in the 2nd/3rd trimester of gestation were enrolled, provided with ART and self-selected their infant-feeding modality. Infants received nevirapine and cotrimoxazole prophylaxis. At 20 weeks of age, eligible HIV-1-negative infants were randomized to vaccine versus no-treatment arms and followed to 48 weeks of age for assessments of vaccine safety, HIV-1-specific T-cell responses and antibodies to routine childhood vaccines.

Results

Between February and November 2010, 182 mothers were screened, 104 were eligible and followed on ART during pregnancy/postpartum, of whom 73 had eligible infants at 20 weeks postpartum. Thirty-six infants were randomized to vaccine and 37 to no treatment. Eighty-four percent of infants breastfed, and retention at 48 weeks was 99%. Adverse events were rare and similar between the two arms. HIV-1-specific T-cell frequencies in interferon-γ ELISPOT assay were transiently higher in the MVA.HIVA arm (p = 0.002), but not above the threshold for a positive assay. Protective antibody levels were adequate and similar between arms for all routine childhood vaccines except HBV, where 71% of MVA.HIVA subjects compared to 92% of control subjects were protected (p = 0.05).

Conclusions

This trial tested for the first time an MVA-vectored candidate HIV-1 vaccine in HIV-1-exposed infants in Africa, demonstrating trial feasibility and vaccine safety, low immunogenicity, and compatibility with routine childhood vaccinations. These results are reassuring for use of the MVA vector in more potent prime-boost regimens.     

慢性HIV感染者的肠道寄生虫感染

慢性HIV感染者易合并多种感染,其中合并肠道寄生虫感染可造成体内HIV复制增加、慢性腹泻、消瘦及营养不良而加快病情发展.此文就慢性HIV感染者合并的肠道寄生虫感染进行了综述.     

Immunization with an HIV-1 immunogen induces CD4+ and CD8+ HIV-1-specific polyfunctional responses in patients with chronic HIV-1 infection receiving antiretroviral therapy

Development of polyfunctional T lymphocyte responses is critical in the immunological response against HIV-1. Fifty-four HIV-1 infected patients receiving antiretroviral treatment (ART) and immunization with an HIV-1 immunogen or placebo, periodically every 3 months throughout a period of 36 months, were evaluated for the purposes of analysing the development of HIV-1-specific CD4⁺ and CD8⁺ responses. A significant increase of proliferating and IFN-γ producing CD8⁺ HIV-1-specific T cells, of HIV-1-specific precursor frequencies for CD8⁺ and for CD4⁺ T cells and of Gag/pol-specific memory CTL precursors (CTLp) was observed in the immunogen group in comparison to placebo. IL-2 intracellular expression and IFN-γ and TNF- co-expression in HIV-1-specific CD8⁺ T cells were also substantially increased in the immunized group. A negative correlation between viral load and CD3⁺CD4⁺CFSE^low HIV-1-specific lymphoproliferative response and frequency of Gag/pol-specific CTLp was solely observed in the HIV-1 immunogen group. Long-term immunization in patients receiving ART helps to develop HIV-1-specific polyfunctional T cell responses.     

人类疱疹病毒-6型包膜胆固醇对病毒感染作用

目的 研究人类疱疹病毒-6型(HHV-6A)包膜胆固醇在病毒感染宿主细胞过程中的作用.方法 用不同浓度甲基-β-环糊精(MβCD)作用于HHV-6A GS株,经20%蔗糖缓冲液梯度离心,去除甲基-β-环糊精并纯化病毒,分别感染HSB-2和Jurkat细胞,采用免疫荧光实验(IFA),流式细胞术及免疫蛋白杂交等方法检测病毒在去除胆固醇后,对宿主细胞的结合、融合、进入的影响.结果 当HHV-6A包膜胆固醇被10mmol/L甲基-β-环糊精去除后,未检测到抗-即时早期蛋白(IE1)的表达,其感染性遭到破坏,但可以部分被外源性胆固醇所恢复,50mmol/L的外源胆固醇就可以使经2.5mmol/L MβCD处理的病毒部分恢复其感染力.与未经MβCD处理的HHV-6A比较,病毒尚能结合宿主细胞,其结合能力稍微受到了影响,但病毒不能进入靶细胞,其感染性及诱导细胞融合的能力显著减弱.结论 HHV-6A包膜胆固醇在细胞融合过程中起着重要作用,同时也是病毒进入宿主细胞的关键因素.