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1.  Dysregulated B Cell Expression of RANKL and OPG Correlates with Loss of Bone Mineral Density in HIV Infection 
PLoS Pathogens  2014;10(11):e1004497.
HIV infection is associated with high rates of osteopenia and osteoporosis, but the mechanisms involved are unclear. We recently reported that bone loss in the HIV transgenic rat model was associated with upregulation of B cell expression of the key osteoclastogenic cytokine receptor-activator of NF-κB ligand (RANKL), compounded by a simultaneous decline in expression of its physiological moderator, osteoprotegerin (OPG). To clinically translate these findings we performed cross-sectional immuno-skeletal profiling of HIV-uninfected and antiretroviral therapy-naïve HIV-infected individuals. Bone resorption and osteopenia were significantly higher in HIV-infected individuals. B cell expression of RANKL was significantly increased, while B cell expression of OPG was significantly diminished, conditions favoring osteoclastic bone resorption. The B cell RANKL/OPG ratio correlated significantly with total hip and femoral neck bone mineral density (BMD), T- and/or Z-scores in HIV infected subjects, but revealed no association at the lumbar spine. B cell subset analyses revealed significant HIV-related increases in RANKL-expressing naïve, resting memory and exhausted tissue-like memory B cells. By contrast, the net B cell OPG decrease in HIV-infected individuals resulted from a significant decline in resting memory B cells, a population containing a high frequency of OPG-expressing cells, concurrent with a significant increase in exhausted tissue-like memory B cells, a population with a lower frequency of OPG-expressing cells. These data validate our pre-clinical findings of an immuno-centric mechanism for accelerated HIV-induced bone loss, aligned with B cell dysfunction.
Author Summary
HIV infection causes significant bone loss and skeletal deterioration, leading to fractures that are often devastating and incur significant financial burden on patients and their families. HIV-infected individuals have up to a five-fold higher risk of bone fractures, and the increasing average age of people living with HIV/AIDS has triggered fears of an impending epidemic of bone fractures in this population. Antiretroviral therapy, used to manage HIV infection, fails to prevent, but rather paradoxically accelerates skeletal decline. The underlying mechanisms of HIV-induced bone loss are poorly understood. The aim of this study was to clarify the mechanisms of bone loss in HIV-infected patients, in an effort to better understand how bone loss and fractures occur, and consequently how it can be prevented in this population. The cytokine RANKL (Receptor Activator of Nuclear Factor kappa-B Ligand) helps induce bone loss. We show that RANKL expression was increased in immune cells in HIV-infected individuals. Another cytokine, osteoprotegerin (OPG), counteracts the activity of RANKL, and therefor helps prevent bone loss. OPG expression by the same immune cells was decreased in HIV-infected individuals. We conclude that disrupted immune cell expression of RANKL and OPG in HIV-infected patients contributes to bone loss.
doi:10.1371/journal.ppat.1004497
PMCID: PMC4231117  PMID: 25393853
2.  OUTCOMES FOR CRITICALLY ILL PATIENTS WITH HIV AND SEVERE SEPSIS IN THE ERA OF HIGHLY ACTIVE ANTIRETROVIRAL THERAPY 
Journal of Critical Care  2011;27(1):51-57.
RATIONALE
With the advent of Highly Active Antiretroviral Therapy (HAART), sepsis has become a more frequent ICU diagnosis for patients with HIV infections. Yet, little is known about the etiologies of acute infections in critically ill patients with HIV and the factors that affect in-hospital mortality.
METHODS
Cases of patients with HIV requiring intensive care specifically for severe sepsis were identified over 27 months. Demographic information, variables related to acute illness severity, variables related to HIV infection, and all acute infections contributing to ICU stay were recorded.
RESULTS
Of 990 patients admitted to the ICU with severe sepsis, 136 (13.7%) were HIV-infected. There were 194 acute infections among the 125 patients with full data available; 112 of the infections were nosocomial/healthcare-associated, 55 were AIDS-related, and 27 were community-acquired. Patients with nosocomial/healthcare-associated and AIDS-related infections had lower CD4 counts and were less likely to be on HAART (p<0.05). The inpatient mortality was 42%. In a multivariable logistic regression model, only the APACHE II score (odds ratio, OR 1.12, 95% CI 1.02–1.23) was significantly associated with hospital mortality, although any HAART use (OR 0.53, 95% CI 0.22–1.33, p=0.18) approached statistical significance.
CONCLUSIONS
In this large cohort study, nosocomial/healthcare-associated infections were common in ICU patients with HIV and severe sepsis. Hospital mortality was associated with acute illness severity, but not clearly associated with variables related to HIV infection. Interventions that aim to prevent or more effectively treat nosocomial infections in critically ill patients with HIV may favorably impact clinical outcomes.
doi:10.1016/j.jcrc.2011.08.015
PMCID: PMC3269533  PMID: 22033058
3.  Antiretroviral therapy initiated during acute HIV infection fails to prevent persistent T cell activation 
Initiation of ART during acute HIV-1 infection may prevent persistent immune activation. We analyzed longitudinal CD38+HLA-DR+ CD8+ T cell percentages in 31 acutely infected individuals who started early (median 43 days since infection) and successful ART, and maintained viral suppression through 96 weeks. Pre-therapy a median of 72.6% CD8+ T cells were CD38+HLA-DR+, and while this decreased to 15.6% by 96 weeks, it remained substantially higher than seronegative controls (median 8.9%, p=0.008). Shorter time to suppression predicted lower activation at 96 weeks. These results support the hypothesis that very early events in HIV-1 pathogenesis may result in prolonged immune dysfunction.
doi:10.1097/QAI.0b013e318285cd33
PMCID: PMC3683110  PMID: 23314410
acute HIV infection; antiretroviral therapy; immune activation; viral dynamics; NNRTIs
4.  A Switch in Therapy to a Reverse Transcriptase Inhibitor Sparing Combination of Lopinavir/Ritonavir and Raltegravir in Virologically Suppressed HIV-Infected Patients: A Pilot Randomized Trial to Assess Efficacy and Safety Profile: The KITE Study 
AIDS Research and Human Retroviruses  2012;28(10):1196-1206.
Abstract
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-RNA<50 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/mm3. 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-RNA<50 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.
doi:10.1089/aid.2011.0336
PMCID: PMC3448110  PMID: 22364141
5.  Global HIV/AIDS Medicine 
Emerging Infectious Diseases  2008;14(6):1006-1007.
doi:10.3201/eid1406.080258
PMCID: PMC2600274
6.  Immune Activation Mediated Change in Alpha-1-Acid Glycoprotein: Impact on Total and Free Lopinavir Plasma Exposure 
Journal of clinical pharmacology  2011;51(11):1539-1548.
Background
Immune mediated changes in circulating α-1-acid glycoprotein (AAG), a type 1 acute phase protein, which binds protease inhibitors (PI), may alter protein binding and contribute to PI's pharmacokinetic (PK) variability.
Methods
In a prospective, 2-phase intensive PK study on antiretroviral naive human immunodeficiency virus (HIV)-infected subjects treated with a lopinavir-/ritonavir-based regimen, steady state PK sampling and AAG assays were performed at weeks 2 and 16 of treatment.
Results
Median entry age was 43 years (n = 16). Median plasma log10 HIV-1 RNA, CD4 T-cell counts, and AAG were 5.16 copies/mL, 28 cells/μL, and 143 mg/dL, respectively.The total lopinavir area under the concentration time curve (AUC12_total) and maximum concentration (Cmax_total) changed linearly with AAG at mean rates of 16±7 mg*hr/L (slope ± SE); P = .04, and 1.6 ± 0.6 mg/L, P = .02, per 100 mg/dL increase in AAG levels, respectively (n = 15).A 29% drop in AAG levels between week 2 and week 16 was associated with 14% (geometric mean ratio [GMR] = 0.86; 90% confidence interval [CI] = 0.74-0.98) and 13% (GMR = 0.87; 90% CI = 0.79-0.95) reduction in AUC12_total and Cmax_total, respectively. Neither free lopinavir PK parameters nor antiviral activity (HIV-1 RNA average AUC minus baseline) was affected by change in plasma AAG.
Conclusions
Changes in plasma AAG levels alter total lopinavir concentrations, but not the free lopinavir exposure or antiviral activity. This observation may have implications in therapeutic drug monitoring.
doi:10.1177/0091270010385118
PMCID: PMC3128238  PMID: 21209245
antiretroviral drugs; pharmacokinetics; protein binding
7.  Tuberculosis Biomarker and Surrogate Endpoint Research Roadmap 
The Centers for Disease Control and Prevention and National Institutes of Health convened a multidisciplinary meeting to discuss surrogate markers of treatment response in tuberculosis. The goals were to assess recent surrogate marker research and to provide specific recommendations for (1) the qualification and validation of biomarkers of treatment outcome; (2) the standardization of specimen and data collection for future clinical trials, including a minimum set of samples and collection time points; and (3) the creation of a specimen repository to support biomarker testing. This article summarizes these recommendations and provides a roadmap for their implementation.
doi:10.1164/rccm.201105-0827WS
PMCID: PMC3208659  PMID: 21737585
8.  HIV-1 RNA Rectal Shedding Is Reduced in Men With Low Plasma HIV-1 RNA Viral Loads and Is Not Enhanced by Sexually Transmitted Bacterial Infections of the Rectum 
The Journal of Infectious Diseases  2011;204(5):761-767.
Background. Among human immunodeficiency virus (HIV)–infected men who have sex with men (MSM) taking combination antiretroviral therapy (cART), the impact of rectal sexually transmitted infections (STIs) on rectal HIV-1 shedding is unknown.
Methods. Human immunodeficiency virus type 1 (HIV-1) RNA was quantified from rectal swabs collected for Neisseria gonorrhoeae (GC) and Chlamydia trachomatis (CT) screening of HIV-1-infected MSM. Correlations of STIs with rectal viral load were explored using multinomial regression modeling. HIV-1 coreceptor tropism was predicted from sequencing in a subset of men.
Results. Thirty-one (39%) of 80 men (59 prescribed combination antiretroviral therapy [cART]) had HIV detected in 38 (42%) of 91 rectal swabs. Rectal HIV detection was associated with plasma virus loads above 3.15 log10 copies/mL (95% confidence limit [CL] 2.73, 3.55) and paired rectal viral loads and plasma viral loads were correlated (Kendall’s tau [τ] 0.68, Spearman rho [P] = .77). Rectal STIs and abnormal anal cytology were not associated with rectal viral load. HIV coreceptor distribution was very similar between the plasma and rectum in 3 of 4 men.
Conclusions. Plasma and rectal viral load were correlated, and rectal STIs did not increase the likelihood of detecting HIV in the rectal secretions in MSM, including those with low or undetectable plasma viral load. Suppressing plasma viral load is likely to reduce risk of HIV transmission to insertive partners.
doi:10.1093/infdis/jir400
PMCID: PMC3156109  PMID: 21844302
9.  Liver Enzymes Elevation and Immune Reconstitution Among Treatment-Naïve HIV-Infected Patients Instituting Antiretroviral Therapy 
Objectives
Because liver enzymes elevation (LEE) complicates antiretroviral (ARV) therapy, and because the strongest risk factor for ARV-related LEE is HBV/HCV coinfection, it is speculated that ARV-related LEE may be a form of immune reconstitution disease. This study summarizes the relation between immune reconstitution, ARV-induced LEE, and HBV/HCV coinfection.
Methods
Medical records of ARV-naïve HIV-infected patients initiating ARV were reviewed for hepatitis coinfection, LEE (grade ≥2 AST/ALT) and changes in CD4 T-cell counts over time in an urban HIV clinic. Risk factors for LEE were statistically evaluated, and changes in CD4 T-cell counts were estimated by a mixed-effects linear model.
Results
Predictors of LEE included HBV/HCV coinfection (OR = 6.44) and stavudine use (OR = 2.33). Nelfinavir use was protective (OR = 0.45). The mean rate of change in CD4 T-cell counts was higher in HBV/HCV coinfected subjects who developed LEE (99 cells/μL per month) compared with non-coinfected subjects who did not develop LEE (59 cells/μL per month, P = 0.03), non-coinfected subjects who developed LEE (36 cells/μL per month, P = 0.01), and coinfected subjects who did not develop LEE, 38% higher (62 cells/μL per month; P = 0.11)
Conclusions
A more robust immune restoration was observed among HBV/HCV coinfected subjects who developed liver enzyme elevation after antiretroviral initiation compared with other groups. This finding suggests that ARV-related liver enzyme elevation may be related in part to immune reconstitution, as measured by changes in CD4 T-cell counts.
doi:10.1097/MAJ.0b013e31811ec780
PMCID: PMC3075308  PMID: 18004087
Hepatotoxicity; Liver enzymes elevation; Antiretroviral drugs; Immune reconstitution; HIV/AIDS
10.  High Prevalence of Persistent Parasitic Infections in Foreign-Born, HIV-Infected Persons in the United States 
Background
Foreign-born, HIV-infected persons are at risk for sub-clinical parasitic infections acquired in their countries of origin. The long-term consequences of co-infections can be severe, yet few data exist on parasitic infection prevalence in this population.
Methodology/Principal Findings
This cross-sectional study evaluated 128 foreign-born persons at one HIV clinic. We performed stool studies and serologic testing for strongyloidiasis, schistosomiasis, filarial infection, and Chagas disease based on the patient's country of birth. Eosinophilia and symptoms were examined as predictors of helminthic infection. Of the 128 participants, 86 (67%) were male, and the median age was 40 years; 70 were Mexican/Latin American, 40 African, and 18 from other countries or regions. Strongyloides stercoralis antibodies were detected in 33/128 (26%) individuals. Of the 52 persons from schistosomiasis-endemic countries, 15 (29%) had antibodies to schistosome antigens; 7 (47%) had antibodies to S. haematobium, 5 (33%) to S. mansoni, and 3 (20%) to both species. Stool ova and parasite studies detected helminths in 5/85 (6%) persons. None of the patients tested had evidence of Chagas disease (n = 77) or filarial infection (n = 52). Eosinophilia >400 cells/mm3 was associated with a positive schistosome antibody test (OR 4.5, 95% CI 1.1–19.0). The only symptom significantly associated with strongyloidiasis was weight loss (OR 3.1, 95% CI 1.4–7.2).
Conclusions/Significance
Given the high prevalence of certain helminths and the potential lack of suggestive symptoms and signs, selected screening for strongyloidiasis and schistosomiasis or use of empiric antiparasitic therapy may be appropriate among foreign-born, HIV-infected patients. Identifying and treating helminth infections could prevent long-term complications.
Author Summary
Undiagnosed and untreated parasitic infections can have severe consequences for human immunodeficiency virus (HIV)-infected persons. An estimated 2 billion people worldwide are infected with soil-transmitted helminths and schistosomiasis, yet there are few data on the prevalence in HIV-infected immigrants to more developed countries. This information could help clinicians determine what testing is needed and what signs or symptoms to expect. We performed serologic, stool, and urine testing for selected parasites in 128 foreign-born persons receiving care at an HIV clinic in Atlanta, Georgia. We found that 26% had serologic evidence of infection with Strongyloides stercoralis and 29% had serologic evidence of schistosomiasis. Because these were likely chronic processes, symptoms and signs were often absent; only weight loss was significantly associated with strongyloidiasis. High eosinophil counts were also associated with parasitic infection. This study suggests the need for targeted screening of foreign-born, HIV-infected persons for parasitic infections (mainly strongyloidiasis and schistosomiasis) or the use of empiric antiparasitic therapy, particularly among those with unexplained eosinophilia. Although there are established guidelines for screening of refugees, health care providers should consider the risk of these organisms in patients who have entered the United States through other pathways.
doi:10.1371/journal.pntd.0001034
PMCID: PMC3075235  PMID: 21532747
11.  Lopinavir/Ritonavir Pharmacokinetic Profile: Impact of Sex and Other Covariates Following a Change From Twice-Daily to Once-Daily Therapy 
Journal of clinical pharmacology  2007;47(8):970-977.
The aim of this study was to determine the impact of sex on the pharmacokinetics of lopinavir/ritonavir. Interaction between lopinavir/ritonavir and tenofovir was also evaluated. Steady-state plasma samples were obtained from virologically suppressed HIV-infected patients on lopinavir/ritonavir 800/200-mg soft gel capsule taken once daily. Drug assays were performed by high-performance liquid chromatography. Pharmacokinetic parameters estimated by noncompartmental method were reported as 90% confidence intervals (CIs) about the geometric mean ratio (GMR). There were 9 males and 11 females. No sex differences were observed in lopinavir/ritonavir pharmacokinetics profile. The GMRsex (women compared with men) for lopinavir area under the concentration–time curve (AUC24), maximum concentration (Cmax), and minimum concentration (Cmin) was 0.95 (90% CI, 0.70–1.29), 0.88 (90% CI, 0.67–1.15), and 1.27 (90% CI, 0.60–2.66), respectively. Similarly, the GMRsex for ritonavir AUC24, Cmax, and Cmin was 0.84 (90% CI, 0.57–1.24), 0.79 (90% CI, 0.50–1.22), and 1.02 (90% CI, 0.58–1.80), respectively. Tenofovir coadministration led to a reduction in lopinavir/ritonavir plasma exposure, giving a lopinavir GMRtenofovir for Cmax of 0.72 (90% CI, 0.57–0.93) and AUC24 of 0.74 (90% CI, 0.56–0.98), respectively. No difference in lopinavir/ritonavir plasma concentrations between sexes was demonstrated in this study. However, tenofovir coadministration lowered lopinavir/ritonavir plasma exposure.
doi:10.1177/0091270007302564
PMCID: PMC3073482  PMID: 17615254
Gender- or sex-related differences; lopinavir pharmacokinetics
12.  Pharmacokinetics of an Indinavir-Ritonavir-Fosamprenavir Regimen in Patients with Human Immunodeficiency Virus 
Pharmacotherapy  2008;28(1):74-81.
Study Objective
To evaluate the pharmacokinetic compatibility of a ritonavir-boosted indinavir-fosamprenavir combination among patients with human immunodeficiency virus (HIV).
Design
Single-center, nonrandomized, prospective, multiple-dose, two-phase pharmacokinetic study.
Setting
University research center.
Patients
Eight adult patients with HIV infection who had been receiving and tolerating indinavir 800 mg–ritonavir 100 mg twice/day for at least 2 weeks.
Intervention
After 12-hour pharmacokinetic sampling was performed on all patients (period A), fosamprenavir (a prodrug of amprenavir) 700 mg twice/day was coadministered for 5 days, with a repeat 12-hour pharmacokinetic sampling performed on the fifth day (period B).
Measurements and Main Results
Pharmacokinetic parameters were determined for indinavir, ritonavir, and amprenavir: area under the concentration-time curve from time 0 to 12 hours after dosing (AUC0–12), maximum plasma concentration (Cmax), and 12-hour plasma concentration (C12). For each parameter, the geometric mean, as well as the geometric mean ratio (GMR) comparing period B with period A, were calculated. Indinavir Cmax was lowered by 20% (GMR 0.80, 95% confidence interval [CI] 0.67–0.96), AUC0–12 was lowered by 6% (GMR 0.94, 95% CI 0.74–1.21), and C12 was increased by 28% (GMR 1.28, 95% CI 0.78–2.10). Ritonavir AUC0–12 was 20% lower (GMR 0.80, 95% CI 0.54–1.19), Cmax was 15% lower (GMR 0.85, 95% CI 0.55–1.32), and C12 was 7% lower (GMR 0.93, 95% CI 0.49–1.76). With the exception of indinavir Cmax, the changes in indinavir and ritonavir pharmacokinetic parameters observed after fosamprenavir coadministration were not statistically significant. The geometric means of amprenavir AUC0–12, Cmax, and C12 were 41,517 ng•hour/ml (95% CI 30,317–56,854 ng•hr/ml), 5572 ng/ml (95% CI 4330–7170 ng/ml), and 2421 ng/ml (95% CI 1578–3712 ng/ml), respectively.
Conclusion
The combination of indinavir 800 mg–ritonavir 100 mg–fosamprenavir 700 mg twice/day appears to be devoid of a clinically significant drug-drug interaction and should be evaluated as an alternative regimen in salvage HIV treatment. This combination may be suitable as part of a background regimen to optimize the therapeutic benefit of newer classes of antiretroviral agents such as the integrase and coreceptor inhibitors in the treatment of multidrug-resistant viruses.
doi:10.1592/phco.28.1.74
PMCID: PMC3073489  PMID: 18154477
antiretroviral pharmacokinetics; ritonavir-boosted double–protease inhibitor combination; indinavir; fosamprenavir
13.  Culturally-adapted and audio-technology assisted HIV/AIDS awareness and education program in rural Nigeria: a cohort study 
Background
HIV-awareness programs tailored toward the needs of rural communities are needed. We sought to quantify change in HIV knowledge in three rural Nigerian villages following an integrated culturally adapted and technology assisted educational intervention.
Methods
A prospective 14-week cohort study was designed to compare short-term changes in HIV knowledge between seminar-based education program and a novel program, which capitalized on the rural culture of small-group oral learning and was delivered by portable digital-audio technology.
Results
Participants were mostly Moslem (99%), male (53.5%), with no formal education (55%). Baseline HIV knowledge was low (<80% correct answers for 9 of the 10 questions). Knowledge gain was higher (p < 0.0001 for 8 of 10 questions) in the integrated culturally adapted and technology-facilitated (n = 511) compared with the seminar-based (n = 474) program.
Conclusions
Baseline HIV-awareness was low. Culturally adapted, technology-assisted HIV education program is a feasible cost-effective method of raising HIV awareness among low-literacy rural communities.
doi:10.1186/1472-698X-10-2
PMCID: PMC2834647  PMID: 20181073
14.  Impaired Hepatitis C Virus (HCV)-Specific Effector CD8+ T Cells Undergo Massive Apoptosis in the Peripheral Blood during Acute HCV Infection and in the Liver during the Chronic Phase of Infection▿  
Journal of Virology  2008;82(20):9808-9822.
A majority of patients infected with hepatitis C virus (HCV) do not sustain an effective T-cell response, and viremia persists. The mechanism leading to failure of the HCV-specific CD8+ T-cell response in patients developing chronic infection is unclear. We investigated apoptosis susceptibility of HCV-specific CD8+ T cells during the acute and chronic stages of infection. Although HCV-specific CD8+ T cells in the blood during the acute phase of infection and in the liver during the chronic phase were highly activated and expressed an effector phenotype, the majority was undergoing apoptosis. In contrast, peripheral blood HCV-specific CD8+ T cells during the chronic phase expressed a resting memory phenotype. Apoptosis susceptibility of HCV-specific CD8+ T cells was associated with very high levels of programmed death-1 (PD-1) and low CD127 expression and with significant functional T-cell deficits. Further evaluation of the “death phase” of HCV-specific CD8+ T cells during acute HCV infection showed that the majority of cells were dying by a process of cytokine withdrawal, mediated by activated caspase 9. Contraction during the acute phase occurred rapidly via this process despite the persistence of the virus. Remarkably, in the chronic phase of HCV infection, at the site of infection in the liver, a substantial frequency of caspase 9-mediated T-cell death was also present. This study highlights the importance of cytokine deprivation-mediated apoptosis with consequent down-modulation of the immune response to HCV during acute and chronic infections.
doi:10.1128/JVI.01075-08
PMCID: PMC2566282  PMID: 18667503
15.  Diversity, Divergence, and Evolution of Cell-Free Human Immunodeficiency Virus Type 1 in Vaginal Secretions and Blood of Chronically Infected Women: Associations with Immune Status 
Journal of Virology  2005;79(15):9799-9809.
Most human immunodeficiency virus type 1 (HIV-1) infections are believed to be the result of exposure to the virus in genital secretions. However, prevention and therapeutic strategies are usually based on characterizations of HIV-1 in blood. To understand better the dynamics between HIV-1 quasispecies in the genital tract and blood, we performed heteroduplex assays on amplified env products from cell-free viral RNA in paired vaginal secretion (VS) and blood plasma (BP) samples of 14 women followed for 1.5 to 3.5 years. Diversity and divergence were less in VS than in BP (P = 0.03 and P < 0.01, respectively), and divergence at both sites was correlated with blood CD4+ cell levels (VS, P = 0.05; BP, P = 0.01). Evolution of quasispecies was observed in 58% of the women; the loss or gain of quasispecies in VS or BP was always accompanied by such changes at the other site. In addition, sustained compartmentalization of quasispecies in VS was found for four women, even as CD4+ cell levels decreased to low levels (<50 cells/μl). Quasispecies changes over time were associated with fluctuations in CD4+ cell levels; concordant increases or decreases in VS and BP divergence had greater CD4+ cell level changes than intervals with discordant changes (P = 0.05), and women with evolving quasispecies had greater decreases in CD4+ cell levels compared to that for women who maintained the same quasispecies (P < 0.05). Thus, diversity, divergence, and evolution of cell-free HIV-1 in VS can be different from that in BP, and dynamics between their respective quasispecies are associated with changes in CD4+ cell levels.
doi:10.1128/JVI.79.15.9799-9809.2005
PMCID: PMC1181596  PMID: 16014941
16.  Specificity of the Antibody Response to the Pneumococcal Polysaccharide and Conjugate Vaccines in Human Immunodeficiency Virus-Infected Adults 
Nonspecific antibodies, which are thought to be nonprotective, have been shown to contribute a substantial proportion of the measured concentration in the standardized immunoglobulin G (IgG) enzyme-linked immunosorbent assay (ELISA) for pneumococcal polysaccharide capsular antibodies. The presence of such antibodies in human immunodeficiency virus (HIV)-infected persons has not been evaluated. The amount of nonspecific antibodies is proportional to the reduction in IgG antibody concentration that occurs with serum absorption with the heterologous polysaccharide 22F. We measured the amount of nonspecific antibodies before and after vaccination with the pneumococcal conjugate vaccine (PCV; n = 33) or the pneumococcal polysaccharide vaccine (PPV; n = 34) in HIV-infected adults with CD4 counts of ≥200 cells/mm3. Blood was drawn before and 2 months after vaccination. For prevaccination sera, we found a substantial amount of nonspecific antibodies for serotypes 4, 6B, 9V, and 23F (23 to 47% of measured IgG concentration), but not for serotype 14. There tended to be proportionately less nonspecific antibodies in postvaccine sera than prevaccine sera for PCV, but not for PPV. Subjects with a low HIV viral load (≤400 copies/ml) had proportionately more nonspecific antibodies than those with higher viral load before and after both vaccines. After 22F absorption, the geometric mean concentrations of antibodies were significantly higher post-PCV than post-PPV for the high viral load group for all five serotypes, but for no serotypes in the low viral load group. These findings confirm that absorption with a heterologous pneumococcal polysaccharide (e.g., 22F) is necessary to remove nonspecific antibodies in a standardized IgG ELISA for pneumococcal capsular antibodies in HIV-infected adults.
doi:10.1128/CDLI.11.1.137-141.2004
PMCID: PMC321324  PMID: 14715560
17.  Detection of Infectious Human Immunodeficiency Virus Type 1 in Female Genital Secretions by a Short-Term Culture Method 
Journal of Clinical Microbiology  2003;41(9):4081-4088.
Infectious human immunodeficiency virus type 1 (HIV-1) is difficult to detect in female genital secretions by standard virus culture techniques. To improve detection of cell-free HIV-1 in female genital secretions, we adapted a short-term assay that uses the multinuclear-activation galactosidase indicator (MAGI) assay. When vaginal lavages from HIV-1-infected women were tested with the adapted MAGI assay, 25 (64%) of 39 lavages with detectable, cell-free HIV-1 RNA were shown to have infectious virus. No infectious virus was found in 10 vaginal lavages from HIV-1-infected women with undetectable vaginal viral loads. Significantly (P < 0.01) more lavages from HIV-1-infected women tested positive for infectious virus by the MAGI assay than by standard peripheral blood mononuclear cell (PBMC) coculture, which detected infectious virus in only 6 (17%) of 35 vaginal lavages. Lavages with viral loads of >10,000 copies per lavage yielded significantly (P < 0.01) more positive cultures than those with <10,000 copies by using the MAGI assay. Detection of infectious HIV-1 in vaginal lavages was not associated with the presence of genital tract infections or CD4+-T-cell counts. However, although the results were not significant (P = 0.08), the MAGI assay detected infectious virus from more vaginal lavages at a vaginal pH of ≥4.5 than at a pH of <4.5. These results indicate that the MAGI assay is more sensitive than PBMC culture methods for detecting infectious virus in female genital secretions. Accurate measurements of infectious virus in genital secretions will improve studies that evaluate sexual transmission of HIV-1.
doi:10.1128/JCM.41.9.4081-4088.2003
PMCID: PMC193780  PMID: 12958229
18.  Clinical Comparison of an Enhanced-Sensitivity Branched-DNA Assay and Reverse Transcription-PCR for Quantitation of Human Immunodeficiency Virus Type 1 RNA in Plasma 
Journal of Clinical Microbiology  1998;36(3):716-720.
The performance characteristics of an enhanced-sensitivity branched-DNA assay (bDNA) (Quantiplex HIV-1 version 2.0; Chiron Corp., Emeryville, Calif.) and a reverse transcription (RT)-PCR assay (AMPLICOR HIV-1 Monitor; Roche Diagnostic Systems, Inc., Branchburg, N.J.) were compared in a molecular diagnostic laboratory. Samples used in this evaluation included linearity and reproducibility panels made by dilution of a human immunodeficiency virus type 1 (HIV-1) stock culture of known virus particle count in HIV-1-negative plasma, a subtype panel consisting of HIV-1 subtypes A through F at a standardized level, and 64 baseline plasma specimens from HIV-1-infected individuals. Plots of log10 HIV RNA copies per milliliter versus log10 nominal virus particles per milliliter demonstrated that both assays were linear over the stated dynamic ranges (bDNA, r = 0.98; RT-PCR, r = 0.99), but comparison of the slopes of the regression lines (bDNA, m = 0.96; RT-PCR, m = 0.83) suggested that RT-PCR had greater proportional systematic error. The between-run coefficients of variation for bDNA and RT-PCR were 24.3 and 34.3%, respectively, for a sample containing 1,650 nominal virus particles/ml and 44.0 and 42.7%, respectively, for a sample containing 165 nominal virus particles/ml. Subtypes B, C, and D were quantitated with similar efficiencies by bDNA and RT-PCR; however, RT-PCR was less efficient in quantitating subtypes A, E, and F. One non-B subtype was recognized in our clinical specimens based on the ratio of values obtained with the two methods. HIV-1 RNA was quantitated in 53 (83%) baseline plasma specimens by bDNA and in 55 (86%) specimens by RT-PCR. RT-PCR values were consistently greater than bDNA values, with population means of 142,419 and 67,580 copies/ml, respectively (P < 0.01). The results were highly correlated (r = 0.91), but the agreement was poor (mean difference in log10 copies per milliliter ± 2 standard deviations, 0.45 ± 0.61) for the 50 clinical specimens that gave discrete values with both methods.
PMCID: PMC104614  PMID: 9508301

Results 1-18 (18)