HIV感染者、发病者及HAART治疗者NK细胞亚群变化研究

目的探讨HIV感染者、发病者和进行高效抗逆转录病毒疗法(HAART)的治疗者NK细胞亚群的变化情况。方法取新鲜外周全血,用荧光标记的单克隆抗体进行染色,经流式细胞仪检测分析HIV感染者、发病者和HAART治疗者NK细胞亚群的变化。结果 HIV感染者、发病者CD56dimCD16+NK细胞的百分比显著低于HIV抗体阴性健康对照;CD56-CD16+、CD56briCD16-/+NK细胞的百分比显著高于HIV抗体阴性健康对照;HAART治疗者CD56dimCD16+、CD56-CD16+和CD56briCD16-/+NK细胞亚群的百分比与HIV抗体阴性健康对照相比不再有显著差异。结论 HIV感染改变了NK细胞亚群的构成,HAART治疗后NK细胞亚群的比例可得到部分恢复。     

HIV-protease inhibitors contribute to P-glycoprotein efflux function defect in peripheral blood lymphocytes from HIV-positive patients receiving HAART

P-glycoprotein (P-gp) has been found expressed in normal human cells, such as bone marrow and peripheral blood cells. The aim of this study was to investigate whether HIV-protease inhibitors (HIV-PIs) interact with P-gp efflux function in normal human peripheral blood lymphocytes (PBLs) and CD34+ progenitor cells. Moreover, we analyzed the in vivo effect of HIV-PIs on P-gp function in PBLs from HIV-infected patients receiving highly active antiretroviral therapy (HAART). We found that HIV-PIs (i.e., ritonavir, saquinavir, nelfinavir and indinavir) interfere with P-gp function in normal PBLs as demonstrated by the reduced efflux of rhodamine 123 (Rh123). This effect was dose-dependent and suggested the following hierarchy: ritonavir > saquinavir > nelfinavir > indinavir. We further analyzed the effect of HIV-PIs on the P-gp function in specific PBLs subsets. Our results show an HIV-PI-induced inhibition of P-gp function in CD4+ and CD8+ T cell subsets, mostly caused by the effect on the naive compartment of both CD4+ and CD8+ T cells. The same inhibitory effect was found in CD34+ hematopoietic progenitor cells. With respect to the in vivo evaluation of P-gp function in PBLs from HIV-infected patients, we found reduced levels of Rh123 efflux that reached the lowest value in AIDS patients receiving HAART. We concluded that HIV-PIs interfere with P-gp function in major cellular targets for HIV infection, such as CD4+ T cells and CD34+ progenitor cells. This ability may contribute to P-gp efflux function defect found in HIV-infected patients and suggests that drug interaction studies are crucial to an overall understanding of the effects of this important group of drugs.     

Viral load responses to HAART is an independent predictor of a new AIDS event in late stage HIV infected patients: prospective cohort study

Background  

A sizeable number of HIV-infected patients receiving HAART do not maintain prolonged virologic suppression. We evaluated long-term HIV viral load (VL) responses to HAART as a risk factor for AIDS events (AE) that is independent of CD4 responses.     

Evaluation of the effect of early and massive tritherapy on the expression of cellular factors potentially implicated in antiretroviral therapy resistance

Treatment of the human immunodeficiency virus (HIV) is restricted by therapeutic escape. The biological mechanisms of this chemoresistance rely notably on the modulation of cell kinase and P-glycoprotein (P-gp) expression. In this study, we investigated, in cynomolgus macaques, the roles of SHIV89.6P infection and of HAART in the mRNA expression of these cell factors. SHIV infection, or associated pathophysiological disorders, increase both thymidine kinase and thymidylate kinase mRNA expression and decrease those of P-gp. On the other hand, the expression of other cell kinases is not modulated. In parallel, HAART accentuates the decrease of P-gp expression and attenuates the increase of kinase expression. On the whole, such metabolic disorders, evidenced herein an animal model of HIV infection, could be involved in HIV-infected patients.     

Immunity to human immunodeficiency virus (HIV) in children with chronic HIV infection receiving highly active antiretroviral therapy

Our objective was to describe the CD4-mediated human immunodeficiency virus (HIV)-specific cell-mediated immunity (CMI) and its virologic and immunologic correlates in children with chronic HIV infection on highly active antiretroviral therapy (HAART). Twelve HIV-infected children on stable antiretroviral therapy with a median level of CD4+ lymphocytes (CD4%) of 25.5% and a median viral load (VL) of 786 HIV RNA copies/ml were enrolled in this study. Nine of these children were also cytomegalovirus (CMV) seropositive. Blood mononuclear cells, stimulated with HIV and CMV antigens, were used to measure lymphocyte proliferation and to enumerate gamma interferon (IFN-gamma)-producing CD4+ cells. HIV CMI and CMV CMI were detected in similar proportions of patients and correlated with each other, although the HIV responses were less robust. HIV lymphocyte proliferation significantly increased with lower HIV VL and showed a trend to increase with higher CD4% and longer time on HAART. The in vitro IFN-gamma response to HIV or CMV was not affected by CD4%, VL, or HAART. Pediatric patients with established HIV infection on HAART frequently exhibit HIV CMI despite undetectable HIV replication. We concluded that the association between HIV CMI and CMV CMI indicates that the same factors govern responsiveness to either antigen.     

Discordant immunologic and virologic responses to highly active antiretroviral therapy are associated with increased mortality and poor adherence to therapy

OBJECTIVE: To examine the independent association of discordant virologic and immunologic responses to highly active antiretroviral therapy (HAART) with mortality. METHODS: A population-based study of 1527 treatment-naive individuals initiating HAART used Cox proportional hazards modeling to determine the independent association of treatment response at 3 to 9 months with nonaccidental mortality. Logistic regression was used to examine associations with discordant responses. RESULTS: Viral load (VL)/CD4 discordant responses were seen in 235 (15.4%) of subjects, and VL/CD4 responses were seen in 179 (11.7%) of subjects. In adjusted Cox regression models, discordant responses were found to be independently associated with an increased risk of mortality (VL/CD4: relative hazard [RH] = 1.87, 95% confidence interval [CI]: 1.15 to 3.04; VL/CD4: RH = 2.47, 95% CI: 1.54 to 3.95). VL/CD4 discordance was found to be associated with increasing age, baseline HIV RNA load <100,000 copies/mL, baseline CD4 counts <50 cells/muL, the use of lamivudine (3TC)/zidovudine (ZDV), and poor adherence to therapy. VL/CD4 discordance was associated with younger age; injection drug use; baseline HIV RNA load >100,000 copies/mL; the use of 3TC/ZDV, didanosine (ddI)/3TC, or ddI/stavudine; and poor adherence to therapy. CONCLUSION: Discordant responses are independently associated with an increased risk of mortality and are, in turn, associated with poor adherence to therapy.     

Regulatory T cells in human immunodeficiency virus-infected patients are elevated and independent of immunological and virological status, as well as initiation of highly active anti-retroviral therapy

Infection with human immunodeficiency virus (HIV) causes a dysregulation of the immune system. This is caused by HIV-specific as well as non-specific mechanisms and has not been explained fully. In particular, knowledge is lacking about the potential role of host-mediated immunosuppressive mechanisms. During recent years it has become evident that a subpopulation of T cells [T regulatory (T(regs))] play a major role in sustaining tolerance to self-antigens. To investigate the influence of initiation of highly active anti-retroviral therapy (HAART) on the T(reg) level in HIV-infected patients we have conducted a prospective study enrolling treatment-naive HIV-infected patients just prior to starting treatment with HAART, measuring levels of T(regs) by flow cytometry and mRNA expression of forkhead box P3 (FoxP3) at weeks 0, 4, 12 and 24 of treatment. In this prospective study neither the percentage of CD4(+)CD25(high+) nor the expression of FoxP3 changed significantly during 24 weeks of HAART. Furthermore, HIV patients have higher T(regs) measured as percentages of CD4(+)CD25(high+) cells paralleled by higher levels of FoxP3 compared with healthy controls. The elevated level of T(regs) was found to be independent of both immunological and virological status, indicating that initiation of HAART has minor effects on the T(reg) level in HIV-infected patients.     

抗病毒治疗后HIV 感染者NKT 样细胞衰老和体外增殖研究

目的:研究高效抗逆转录病毒治疗(Highly active antiretroviral therapy,HAART)后NKT 样细胞衰老和体外增殖情况。方法:选取未接受HAART 治疗、接受HAART 治疗的HIV 感染者以及健康人的外周血细胞,利用流式细胞仪检测接受HAARRT 治疗前后的HIV 感染者NKT 样细胞CD57 的表达情况以及体外增殖能力。结果:HIV 感染者在HAART 治疗前NKT 样细胞的百分数显著低于健康对照组(P<0.01),HAART 治疗后恢复(P<0.05);HAART 治疗前NKT 样细胞CD57 的表达明显高于健康对照组(P<0.01),HAART 治疗后恢复(P<0.05);HAART 治疗前NKT 样细胞体外增殖能力明显低于健康对照组,HAART 治疗后有所恢复。结论:经过HAART 治疗后,HIV 感染者NKT 样细胞的数量、CD57 表达以及体外增殖能力有所恢复。     

Immunity to Human Immunodeficiency Virus (HIV) in Children with Chronic HIV Infection Receiving Highly Active Antiretroviral Therapy

Our objective was to describe the CD4-mediated human immunodeficiency virus (HIV)-specific cell-mediated immunity (CMI) and its virologic and immunologic correlates in children with chronic HIV infection on highly active antiretroviral therapy (HAART). Twelve HIV-infected children on stable antiretroviral therapy with a median level of CD4⁺ lymphocytes (CD4%) of 25.5% and a median viral load (VL) of 786 HIV RNA copies/ml were enrolled in this study. Nine of these children were also cytomegalovirus (CMV) seropositive. Blood mononuclear cells, stimulated with HIV and CMV antigens, were used to measure lymphocyte proliferation and to enumerate gamma interferon (IFN-γ)-producing CD4⁺ cells. HIV CMI and CMV CMI were detected in similar proportions of patients and correlated with each other, although the HIV responses were less robust. HIV lymphocyte proliferation significantly increased with lower HIV VL and showed a trend to increase with higher CD4% and longer time on HAART. The in vitro IFN-γ response to HIV or CMV was not affected by CD4%, VL, or HAART. Pediatric patients with established HIV infection on HAART frequently exhibit HIV CMI despite undetectable HIV replication. We concluded that the association between HIV CMI and CMV CMI indicates that the same factors govern responsiveness to either antigen.     

Strategies for overcoming resistance in HIV-1 infected patients receiving HAART

Highly active antiretroviral therapy (HAART) has fundamentally changed the clinical outcome of HIV infection and AIDS. However, the emergence of drug-resistant HIV variants is a barrier to successful use of HAART, with resistance to one drug often resulting in cross-resistance to many, if not all, others in the same class. The rise in the incidence of drug-resistant variants among newly infected patients also represents a formidable challenge for clinicians. Failure of the current HAART regimen due to drug resistance can severely limit second-line, third-line, and salvage treatment options. Although inadequate exposure of the virus to antiretroviral agents is a prime reason for the emergence of HIV drug-resistant variants, poor adherence to complicated regimens and variability in drug pharmacokinetics (PK), both within and between HIV-infected individuals, can also affect the overall efficacy of antiretroviral agents, promoting emergence of resistant HIV variants. Recent strategies to optimize antiretroviral drug regimens, including assessment of HIV genotype and/or phenotype, the use of protease inhibitor regimens that incorporate PK boosting, and scheduled treatment interruptions, have been explored. Additionally, several newer antiretroviral agents that produce rapid and sustained virologic and immunologic responses as well as novel resistance profiles (e.g. atazanavir and tenofovir) have become available. These characteristics thus increase the likelihood of durable viral suppression.     

Differential upregulation of CD38 on different T-cell subsets may influence the ability to reconstitute CD4+ T cells under successful highly active antiretroviral therapy

BACKGROUND: Immune activation is an independent surrogate marker of CD4 T-cell depletion in HIV-infected patients. Highly active antiretroviral therapy (HAART) reduces disease progression as a direct consequence of suppressing HIV replication. Immune function does not normalize completely in most subjects on HAART, however, perhaps reflecting residual HIV replication. So far, it is unclear to what extent immune activation may influence the evolution of CD4 T-cell counts in patients on HAART. PATIENTS AND METHODS: The expression of CD38 on naive and memory subsets of CD4+ and CD8+ T cells was measured quantitatively by flow cytometry in 62 drug-naive HIV-positive and 30 HIV-uninfected controls. In addition, the evolution of this marker as well as that of some virologic parameters (plasma viremia and proviral load) and CD4 counts were assessed in 25 HIV-infected individuals who initiated HAART and were followed for 12 months. RESULTS: The mean level of CD38 on memory CD4+ and CD8+ T cells as well as in naive CD8+ cells was significantly higher in drug-naive HIV-positive subjects than in HIV-negative controls. Moreover, it was highly correlated with viral load titers. In patients on successful HAART, immune activation declined in all T-cell subsets, particularly among memory CD8+ cells. It remained elevated with respect to HIV-negative controls, however, even after 12 months of HAART. There was a significant correlation between the CD8+ T-cell activation decay and the increase of CD4+ T cells on HAART. Patients with the highest decline in CD8 activation were those showing the highest CD4 T-cell gains after 12 months of therapy. CONCLUSIONS: The level of CD38 expression on different T-cell subsets is differentially upregulated in drug-naive HIV-infected patients. After successful HAART, immune activation decreases in all T-cell subsets, although it still remains elevated in most cases after 12 months of HAART. The extent of immune deactivation under successful HAART correlates with the ability to reconstitute CD4 counts.     

Micronutrient levels and HIV disease status in HIV-infected patients on highly active antiretroviral therapy in the Nutrition for Healthy Living cohort

BACKGROUND: Low serum micronutrient levels were common before widespread use of highly active antiretroviral therapy (HAART) and were associated with adverse outcomes. Few data are available on micronutrient levels in subjects taking HAART. OBJECTIVE: To determine the prevalence of low serum retinol, alpha-tocopherol, zinc, and selenium in HIV-infected subjects taking HAART and to assess the association of micronutrient levels with HIV disease status. DESIGN: Cross-sectional. SETTING: Nutrition for Healthy Living (NFHL) study. PARTICIPANTS: HIV-infected subjects on HAART. METHODS: Retinol, alpha-tocopherol, zinc, and selenium were determined in frozen serum samples from 171 men and 117 women. Low serum levels were defined as retinol <30 microg/dL, selenium <85 microg/L, alpha-tocopherol <500 microg/dL, and zinc <670 microg/L. Association of micronutrient quartiles with CD4 cell count, CD4 count <200 cells/mm, HIV viral load (VL), and undetectable VL was assessed using adjusted multivariate regression. RESULTS: Five percent of men and 14% of women had low retinol, 8% of men and 3% of women had low selenium, and 7% of men and no women had low alpha-tocopherol. Forty percent of men and 36% of women had low zinc, however. Subjects in the upper quartiles of zinc had lower log VL levels than those in the lowest quartile (significant for women). Subjects in the upper quartiles of selenium also tended to have lower VL levels compared with those in the lowest quartile. Surprisingly, women in the upper quartiles of retinol had higher log VLs than those in the lowest quartile. There was no significant association of any micronutrient with CD4 cell count or likelihood of CD4 count <200 cells/mm. The level of CD4 cell count influenced the association of retinol with log VL in men, however. In men with CD4 counts >350 cells/mm, those with higher retinol had higher log VLs compared with the lowest quartile, whereas in men with CD4 counts <350, those with higher retinol levels had lower log VLs compared with the lowest quartile. CONCLUSIONS: Low retinol, alpha-tocopherol, and selenium are uncommon in HIV-infected subjects on HAART. Zinc deficiency remains common, however. Decreased retinol levels in women and in men with CD4 counts >350 cells/mm and increased zinc and selenium levels in both genders may be associated with improved virologic control.     

慢性HIV/AIDS患者T淋巴细胞凋亡与疾病进展关系的研究

目的 探讨慢性未经抗病毒治疗的HIV/AIDS患者T淋巴细胞及各亚群凋亡与疾病进展的相关性.方法 以36例慢性未经抗病毒治疗的HIV/AIDS患者为研究对象,根据CD4细胞计数分为3组:<200个/μl组,200～350个/μl组,>350个/μl组,同时选取16例健康志愿者作对照,分离外周血单核细胞(PBMC)后,采用CD45RO及CD27标记T细胞亚群,Annexin V标记细胞凋亡,用流式细胞仪检测各项指标.其中4例患者及4例健康志愿者的PBMC在体外培养,比较分析体外培养0、3、6、12、24 h不同时间点T细胞凋亡的变化情况.结果 (1)HIV/AIDS患者CD4~+、CD8~+T细胞及各亚群上Annexin V表达百分比均显著高于健康人(P<0.05),但3组患者之间比较差异无统计学意义(P>0.05);(2)HIV/AIDS患者CD4~+、CD8~+T细胞及各业群上Annexin V表达百分比与CD4~+T细胞计数及病毒载显均无显著相关性(P>0.05);(3)随着体外细胞培养时间的延长,HIV/AIDS患者CD4~+T细胞的凋亡及死亡细胞百分比均显著高于健康人(P<0.05),并且HIV/AIDS患者CD4~+T细胞较CD8~+T细胞更易发生凋亡和死亡.结论 HIV/AIDS患者的T细胞凋亡水平显著高于健康人,并且CD4~+T细胞较CD8~+T细胞更易发生凋亡和死亡,但是T细胞凋亡水平与HIV的疾病进展程度并没有相关性.     

Incidence of and risk factors for symptomatic visceral leishmaniasis among human immunodeficiency virus type 1-infected patients from Spain in the era of highly active antiretroviral therapy

The way in which the extensive use of highly active antiretroviral therapy (HAART) has influenced the incidence of visceral leishmaniasis (VL) among human immunodeficiency type 1 (HIV-1)-infected patients is not yet understood. The present study assessed whether the incidence of symptomatic VL in HIV-infected patients has decreased since the introduction of HAART. Likewise, the role of other potential risk factors for VL was also analyzed. Therefore, 479 HIV-1-infected patients receiving antiretroviral treatment, according to the available drugs at each moment, were prospectively followed from April 1989 to June 2000 in two university hospitals in southern Spain. A bone marrow aspiration was performed when patients showed symptoms suggestive of kala-azar. A diagnosis of VL was made when Leishmania amastigotes were seen in Giemsa-stained samples or promastigotes were cultured in specific media. The median follow-up time was 1,380 [8 to 4,536] days. Twenty-one patients were diagnosed with symptomatic VL. The density of incidence of VL has decreased 64.8% as of January 1997, when HAART began to be used extensively in our area. The use of HAART was the main independent factor associated with VL; this therapy was a protective factor (adjusted hazard ratio [HR], 0.05; 95% confidence interval [CI], 0.02 to 0.15). CDC clinical category C at entry in the cohort (HR, 4.08; 95% CI, 1.46 to 11.35) and CD4(+) cell counts below 300 cells/mm(3) during the follow-up (HR, 3.96; 95% CI, 1.56 to 10.01) were also independently associated with kala-azar. A VL diagnosis prior to follow-up and low compliance with antiretroviral therapy were not independently associated with symptomatic VL, although statistical significance was almost reached (P = 0.1 and P = 0.08, respectively). In summary, the use of HAART has led to a fall in the incidence of symptomatic VL in HIV-infected patients. The main risk factor associated with kala-azar emergence in patients infected with HIV is deep immunosuppression.