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In a prospective cross-sectional study we quantified HIV viral load within the alveolar macrophage in a cohort of healthy HIV-infected subjects who did not have medical comorbidities or smoke cigarettes to determine if alveolar macrophage proviral DNA was associated with alveolar macrophage phagocytic immune dysfunction. We enrolled 23 subjects who underwent bronchoscopy and bronchoalveolar lavage. Alveolar macrophages were isolated and HIV-1 RNA was quantified in the cells using the Abbott RealTime HIV-1 Assay. Proviral DNA was qualitatively measured using a modified version of the HIV-1 RNA assay. Phagocytosis measured by incubating alveolar macrophages with FITC-labeled Staphylococcus aureus and determining fluorescence with a Zeiss inverted microscope. Phagocytic index was calculated as (% positive cells × mean channel fluorescence)/100. Sixteen subjects had (+) proviral DNA and seven had (-) proviral DNA in their alveolar macrophages. Of all subjects 100% in both groups were on highly active antiretroviral therapy (HAART). The median plasma viral load was 0 in both groups. HIV-1-infected subjects with (+) proviral DNA in their alveolar macrophages had a significantly lower median alveolar macrophage phagocytic index compared to those with (-) proviral DNA in their alveolar macrophages [11.8 (IQR 4.8-39.0) vs. 64.9 (IQR 14.0-166.0), p = 0.05]. Alveolar macrophages harbor HIV even in otherwise healthy subjects with undetectable plasma viral loads, representing a potential reservoir for the virus. In addition, HIV viral replication within the macrophage may impair phagocytosis and other immune functions in the lung, leading to an increased risk for lung infection.

Despite antiretroviral therapy, pneumonias from pathogens such as pneumococcus continue to cause significant morbidity and mortality in HIV-1-infected individuals. Respiratory infections occur despite high CD4 counts and low viral loads; therefore, better understanding of lung immunity and infection predictors is necessary. We tested whether metabolomics, an integrated biosystems approach to molecular fingerprinting, could differentiate such individual characteristics. Bronchoalveolar lavage fluid (BALf ) was collected from otherwise healthy HIV-1-infected individuals and healthy controls. A liquid chromatography-high-resolution mass spectrometry method was used to detect metabolites in BALf. Statistical and bioinformatic analyses used false discovery rate (FDR) and orthogonally corrected partial least-squares discriminant analysis (OPLS-DA) to identify groupwise discriminatory factors as the top 5% of metabolites contributing to 95% separation of HIV-1 and control. We enrolled 24 subjects with HIV-1 (median CD4=432) and 24 controls. A total of 115 accurate mass m/z features from C18 and AE analysis were significantly different between HIV-1 subjects and controls (FDR=0.05). Hierarchical cluster analysis revealed clusters of metabolites, which discriminated the samples according to HIV-1 status (FDR=0.05). Several of these did not match any metabolites in metabolomics databases; mass-to-charge 325.065 ([M+H](+)) was significantly higher (FDR=0.05) in the BAL of HIV-1-infected subjects and matched pyochelin, a siderophore-produced Pseudomonas aeruginosa. Metabolic profiles in BALf differentiated healthy HIV-1-infected subjects and controls. The lack of association with known human metabolites and inclusion of a match to a bacterial metabolite suggest that the differences could reflect the host's lung microbiome and/or be related to subclinical infection in HIV-1-infected patients.

This study compared HIV-1 genotypes shed over time (≤3.5 years) in the vaginal secretions (VS) and blood plasma (BP) of 15 chronically infected women. Analysis of predicted coreceptor tropism (CCR5 = R5, CXCR4 = X4) for quasispecies shedding revealed three patterns: (1) viral quasispecies shed in both VS and BP were restricted to R5-tropism at all time points, (2) quasispecies shed in VS were restricted to R5-tropism at all time points but X4 quasispecies were identified in the BP at one or more time points, and (3) quasispecies shed in matched VS and BP both contained X4-tropic viruses. Overall, the frequency of X4 quasispecies circulation in VS was 2-fold less than in BP and detection of X4 virus in VS was more likely to occur when X4 quasispecies comprised more than 50% of BP viruses (p = 0.01) and when declines in blood CD4+ lymphocyte levels were the greatest (p = 0.038). Additionally, the mean number of predicted N-glycosylation sites between matched VS and BP samples was strongly correlated (r = 0.86, p< 0.0001) with glycosylation densities in the following order (VS R5 = BP R5 > BP X4 > VS X4). The X4 glycosylation densities may result from compartmentalization pressures in the female genital tract or the delayed appearance of these viruses in VS. Our results suggest that the presence of X4 virus in VS is associated with a threshold population of X4 quasispecies in BP, which are increasing during the HIV-induced failure of the human immune system.

A nucleoside reverse transcriptase inhibitor (NRTI) backbone is a recommended component of standard highly active antiretroviral therapy (sHAART). However, long-term NRTI exposure can be limited by toxicities. NRTI class-sparing alternatives are warranted in select patient populations. This is a 48-week single-center, open-label pilot study in which 60 HIV-infected adults with plasma HIV-1 RNA (50 copies/ml) on sHAART were randomized (2:1) to lopinavir/ritonavir (LPV/r) 400/100 mg BID+raltegravir (RAL) 400 mg BID switch (LPV-r/RAL arm) or to continue on sHAART. The primary endpoint was the proportion of subjects with HIV-RNA50 copies/ml at week 48. Secondary efficacy and immunologic and safety endpoints were evaluated. Demographics and baseline lipid profile were similar across arms. Mean entry CD4 T cell count was 493 cells/mm(3). At week 48, 92% [95% confidence interval (CI): 83-100%] of the LPV-r/RAL arm and 88% (95% CI: 75-100%) of the sHAART arm had HIV-RNA50 copies/ml (p=0.70). Lipid profile (mean ± SEM, mg/dl, LPV-r/RAL vs. sHAART) at week 24 was total-cholesterol 194 ± 5 vs. 176 ± 9 (p=0.07), triglycerides 234 ± 30 vs. 133 ± 27 (p=0.003), and LDL-cholesterol 121 ± 6 vs. 110 ± 8 (p=0.27). There were no serious adverse events (AEs) in either arm. Regimen change occurred in three LPV-r/RAL subjects (n=1, due to LPV-r/RAL-related AEs) vs. 0 in sHAART. There were no differences between arms in bone mineral density, total body fat composition, creatinine clearance, or CD4 T cell counts at week 48. In virologically suppressed patients on HAART, switching therapy to the NRTI-sparing LPV-r/RAL combination produced similar sustained virologic suppression and immunologic profile as sHAART. AEs were comparable between arms, but the LPV-r/RAL arm experienced higher triglyceridemia.

A total of six amino acid sequences encoded in conserved regions of the HIV-env (three from gp120 and three from gp41) were selected as potential antigenic domains. These sequences (11-20 amino acids) were fused to the NH2 terminus of beta-galactosidase by recombinant DNA techniques, and the purified chimeric proteins were used to titer (by immunodots) 75 sera from HIV-infected individuals of various stages. All the HIV antigens were recognized by some or all the HIV-seropositive sera but by none of the control sera. Of the three conserved domains in gp41, two are highly immunodominant. All (100%) HIV-seropositive sera reacted with one of these immunodominant domains in titers (approximately 1:100,000) almost two orders of magnitude higher than any other tested domain. This emphasizes the diagnostic value of the epitopes (ERYLKDQLLGIWGCSGKLIC) previously (see Refs. 11 and 12) identified in this domain. A decrease in average antibody titers is observed in late stages of infection for all the antigens tested, yet distribution of antibody reactivity was independent of stage for only three of the six domains. A significantly higher proportion of reactivity of seropositive sera in early stage (62%) compared with late stage (11%) of infection was found for a domain (NVTENFNMWKN) mapped at the NH2 terminus of gp120; serum antibody reactivity with this domain also correlated with a lack of culturable HIV in blood mononuclear cells.