Long-term safety and efficacy of emtricitabine and tenofovir alafenamide vs emtricitabine and tenofovir disoproxil fumarate for HIV-1 pre-exposure prophylaxis: week 96 results from a randomised, double-blind, placebo-controlled, phase 3 trial

BACKGROUND

In DISCOVER, a multinational, randomised controlled trial, emtricitabine and tenofovir alafenamide compared with emtricitabine and tenofovir disoproxil fumarate showed non-inferior efficacy for HIV prevention and improved bone mineral density and renal safety biomarkers at week 48. We report outcomes analysed after all participants had completed 96 weeks of follow-up.

METHODS

This study is an ongoing, randomised, double-blind, multicentre, active-controlled, phase 3, non-inferiority trial done at 94 community, public health, and hospital-associated clinics located in Europe and North America. Adult cisgender men and transgender women who have sex with men, both with a high risk of acquiring HIV as determined by self-reported sexual behaviour or recent sexually transmitted infections, were randomly assigned (1:1) to receive either emtricitabine and tenofovir alafenamide (200/25 mg) tablets daily, with matched placebo tablets (emtricitabine and tenofovir alafenamide group), or emtricitabine and tenofovir disoproxil fumarate (200/300 mg) tablets daily, with matched placebo tablets (emtricitabine and tenofovir disoproxil fumarate group). The primary efficacy outcome was incident HIV infection. Incidence of HIV-1 infection per 100 person-years was assessed when the last participant had completed 96 weeks of follow-up. This trial is registered with ClinicalTrials.gov, number NCT02842086.

FINDINGS

Between Sept 13, 2016, and June 30, 2017, 5387 participants were randomly assigned to receive emtricitabine and tenofovir alafenamide (n=2694) or emtricitabine and tenofovir disoproxil fumarate (n=2693), contributing 10 081 person-years of follow-up. At 96 weeks of follow-up, there were eight HIV infections in participants who had received emtricitabine and tenofovir alafenamide (0·16 infections per 100 person-years [95% CI 0·07-0·31]) and 15 in participants who had received emtricitabine and tenofovir disoproxil fumarate (0·30 infections per 100 person-years [0·17-0·49]). Emtricitabine and tenofovir alafenamide maintained its non-inferiority to emtricitabine and tenofovir disoproxil fumarate for HIV prevention (IRR 0·54 [95% CI 0·23-1·26]). Approximately 78-82% of participants reported taking study medication more than 95% of the time across all study visits. Rates of sexually transmitted infections remained high and similar across groups (21 cases per 100 person-years for rectal gonorrhoea and 28 cases per 100 person-years for rectal chlamydia). Emtricitabine and tenofovir alafenamide continued to show superiority over emtricitabine and tenofovir disoproxil fumarate in all but one of the six prespecified bone mineral density and renal biomarkers. There was more weight gain among participants who had received emtricitabine and tenofovir alafenamide (median weight gain 1·7 kg vs 0·5 kg, p<0·0001).

INTERPRETATION

Emtricitabine and tenofovir alafenamide is safe and effective for longer-term pre-exposure prophylaxis in cisgender men and transgender women who have sex with men.

FUNDING

Gilead Sciences.

Potential use of serum-derived bovine immunoglobulin/protein isolate for the management of COVID-19

COVID‐19 manifests as a mild disease in most people but can progress to severe disease in nearly 20% of individuals. Disease progression is likely driven by a cytokine storm, either directly stimulated by SARS‐CoV‐2 or by increased systemic inflammation in which the gut might play an integral role. SARS‐CoV‐2 replication in the gut may cause increased intestinal permeability, alterations to the fecal microbiome, and increased inflammatory cytokines. Each effect may lead to increased systemic inflammation and the transport of cytokines and inflammatory antigens from the gut to the lung. Few interventions are being studied to treat people with mild disease and prevent the cytokine storm. Serumderived bovine immunoglobulin/protein isolate (SBI) may prevent progression by (1) binding and neutralizing inflammatory antigens, (2) decreasing gut permeability, (3) interfering with ACE2 binding by viral proteins, and (4) improving the fecal microbiome. SBI is therefore a promising intervention to prevent disease progression in COVID‐19 patients.

HIV/HCV therapy with ledipasvir/sofosbuvir after randomized switch to emtricitabine-tenofovir alafenamide-based single-tablet regimens

INTRODUCTION

Guidelines advocate the treatment of HCV in all HIV/HCV co-infected individuals. The aim of this randomized, open-label study (ClinicalTrials.gov identifier: NCT02707601; https://clinicaltrials.gov/ct2/show/NCT02707601) was to evaluate the safety/efficacy of ledipasvir/sofosbuvir (LDV/SOF) co-administered with elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide (E/C/F/TAF) or rilpivirine/F/TAF (R/F/TAF) in HIV-1/HCV co-infected participants.

METHODS

Participants with HIV-1 RNA <50 copies/mL and chronic HCV-genotype (GT) 1 (HCV treatment-naïve ± compensated cirrhosis or HCV treatment-experienced non-cirrhotic) were randomized 1:1 to switch to E/C/F/TAF or R/F/TAF. If HIV suppression was maintained at Week 8, participants received 12 weeks of LDV/SOF. The primary endpoint was sustained HCV virologic response 12 weeks after LDV/SOF completion (SVR12).

RESULTS

Of 150 participants, 148 received ≥1 dose of HIV study drug and 144 received LDV/SOF (72 in each F/TAF group; 83% GT1a, 94% HCV treatment-naïve, 12% cirrhotic). Overall, SVR12 was 97% (95% confidence interval: 93-99%). Black race did not affect SVR12. Of four participants not achieving SVR12, one had HCV relapse, one had HCV virologic non-response due to non-adherence, and two missed the post-HCV Week 12 visit. Of 148 participants, 96% receiving E/C/F/TAF and 95% receiving R/F/TAF maintained HIV suppression at Week 24; no HIV resistance was detected. No participant discontinued LDV/SOF or E/C/F/TAF due to adverse events; one participant discontinued R/F/TAF due to worsening of pre-existing hypercholesterolemia. Renal toxicity was not observed in either F/TAF regimen during LDV/SOF co-administration. In conclusion, high rates of HCV SVR12 and maintenance of HIV suppression were achieved with LDV/SOF and F/TAF-based regimens.

CONCLUSION

This study supports LDV/SOF co-administered with an F/TAF-based regimen in HIV-1/HCV-GT1 co-infected patients.

Serum Bovine Immunoglobulins Improve Inflammation and Gut Barrier Function in Persons with HIV and Enteropathy on Suppressive ART

Background

Systemic inflammation persists in chronic HIV infection and is associated with increased rates of non-AIDS events such as cardiovascular and liver disease. Increased gut permeability and systemic exposure to microbial products are key drivers of this inflammation. Serum-derived bovine immunoglobulin/protein isolate (SBI) supports gut healing in other conditions such as inflammatory bowel disease.

Methods

In this randomized, double-blind study, participants receiving suppressive antiretroviral therapy (ART) with chronic diarrhea received placebo or SBI at 2.5 g BID or 5 g BID for 4 weeks, followed by a 20-week placebo-free extension phase with SBI at either 2.5 or 5 g BID. Intestinal fatty acid binding protein (I-FABP), zonulin, flagellin, lipopolysaccharide (LPS) and LPS-binding protein, and inflammatory markers were measured by ELISA or multiplex assays. Non-parametric tests were used for analysis.

Results

One hundred three participants completed the study. By week 24 SBI significantly decreased circulating levels of I-FABP (-0.35 ng/μL, P=0.002) and zonulin (-4.90 ng/μL, P=0.003), suggesting improvement in gut damage, and interleukin-6 (IL-6) (-0.40 pg/μL, P=0.002), reflecting improvement in systemic inflammation. In participants with the lowest quartile of CD4+ T-cell counts at baseline (189-418 cells/μL), CD4+ T-cell counts increased significantly (26 cells/μL; P=0.002).

Conclusions

Oral SBI may decrease inflammation and warrants further exploration as a potential strategy to improve gut integrity and decrease systemic inflammation among persons receiving prolonged suppressive ART.

Evaluation of oral serum-derived bovine immunoglobulins in HIV-infected patients with chronic idiopathic diarrhea

Objectives To evaluate serum-derived bovine immunoglobulin/protein isolate (SBI) for safety and impact on gastrointestinal (GI) symptoms in HIV patients with chronic idiopathic diarrhea. Methods A multi-center trial comprised of a double-blind, placebo (PBO)-controlled lead-in phase, (participants received PBO or SBI at 2.5 or 5.0 g BID for 4 weeks) followed by a 20-week, PBO-free phase (SBI at either 2.5 or 5.0 g BID). Participants included HIV-infected patients who were virologically suppressed with a history of chronic idiopathic diarrhea, defined as > 3 loose stools per day for ≥ 3 months without an identifiable cause. Safety was evaluated by monitoring adverse events (AEs) and clinical laboratory testing. Health status and changes in GI symptoms were assessed using validated questionnaires. Results SBI was well tolerated by the 103 participants with only 2 withdrawals due to AEs potentially associated with SBI. Mean number of daily unformed stools decreased from about 4 at baseline to less than 2 by week 4 for all study groups. Improvements in several other GI symptoms were also reported. Comparison of the PBO group to SBI groups showed no significant differences, although both SBI cohorts reported significantly improved health status scores. GI symptom improvements were maintained throughout the 20-week PBO-free phase. Conclusions Oral SBI is safe and well tolerated at the doses studied in HIV patients with chronic diarrhea. No conclusions could be drawn regarding impact on GI symptoms. Additional studies are ongoing to examine the biological and immunologic effects of SBI in virologically suppressed HIV-infected patients.

Effect of baseline micronutrient and inflammation status on CD4 recovery post-cART initiation in the multinational PEARLS trial

BACKGROUND & AIMS

Nutritional deficiency and inflammation may impact CD4+ T cell recovery during combination antiretroviral therapy (cART), particularly in resource-limited settings where malnutrition is prevalent. The aim of this study was to investigate the relationship of micronutrient and inflammation biomarkers to CD4 recovery after cART initiation.

METHODS

We conducted a secondary analysis of a random sub-cohort sample (n = 270) from a multinational randomized trial of cART regimen efficacy among 1571 cART-naïve adults. We measured pre-cART serum levels of micronutrients (Vitamin A, B₆, B₁₂, D, total carotenoids, selenium, and iron) and inflammation (C-reactive protein, soluble CD14 (sCD14), IFNγ, TNFα, Interleukin-6, and C-X-C motif chemokine 10 (CXCL10/IP10), EndoCab (IgM)) biomarkers. Biomarker status (i.e. micronutrient deficiency vs. sufficiency and elevated vs. low inflammation) was defined using established cutoffs or quartiles. Mixed-effects linear regression models were used to determine the association of baseline (pre-cART) concentrations of individual biomarkers with CD4 recovery through 96 weeks post-cART initiation.

RESULTS

In models adjusting for time-dependent viral load and baseline CD4 count, age, sex, body mass index, country, treatment regimen, anemia and hypoalbuminemia status, pre-cART vitamin D deficiency was associated with lower CD4 recovery (-14.9 cells/mm³, 95% CI: -27.9, -1.8) compared to sufficiency. In contrast, baseline selenium deficiency (20.8 cells/mm³, 95% CI: 3.3, 38.3), vitamin A deficiency (35.9 cells/mm³, 95% CI: 17.6, 54.3) and high sCD14 (23.4 cells/mm³, 95% CI: 8.9, 37.8) were associated with higher CD4 recovery compared to sufficient/low inflammation status.

CONCLUSIONS

In summary, baseline vitamin D deficiency was associated with diminished CD4 recovery after cART initiation; impaired CD4 recovery may contribute to the poor clinical outcomes recently observed in individuals with vitamin D deficiency. Vitamin A, selenium and sCD14 were associated with CD4 recovery but future studies are needed to further explore these relationships.

Associations of Plasma Cytokine and Microbial Translocation Biomarkers With Immune Reconstitution Inflammatory Syndrome

A nested case-cohort study was performed in participants of a clinical trial of first-line human immunodeficiency virus treatments to investigate plasma biomarkers of inflammation and microbial translocation for their association with immune reconstitution inflammatory syndrome (IRIS). Fifty-one of 1452 participants with baseline CD4 count <350 cells/μL developed IRIS. Plasma from 51 IRIS cases, including 6 stratified by preenrollment CD4 count ≤200 cells/μL, were analyzed and compared to 94 non-IRIS controls. At baseline, CXCL10, lipopolysaccharide, soluble CD14, 16S ribosomal DNA, and interferon-α2 were associated with greater risk of IRIS. Systemic inflammation through persistent monocyte activation and microbial translocation appear to be important in IRIS pathogenesis.

Tissue Pharmacologic and Virologic Determinants of Duodenal and Rectal Gastrointestinal-Associated Lymphoid Tissue Immune Reconstitution in HIV-Infected Patients Initiating Antiretroviral Therapy

Plasma, duodenal, and rectal tissue antiretroviral therapy (ART) drug concentrations, human immunodeficiency virus (HIV) RNA and HIV DNA copy numbers, and recovery of mucosal immunity were measured before and 9 months after initiation of 3 different ART regimens in 26 subjects. Plasma and tissue HIV RNA correlated at baseline and when 9-month declines were compared, suggesting that these compartments are tightly associated. Antiretroviral tissue:blood penetration ratios were above the 50% inhibitory concentration values in almost 100% of cases. There were no correlations between drug concentrations and HIV DNA/RNA. Importantly, no evidence was found for residual viral replication or deficient tissue drug penetration to account for delayed gastrointestinal-associated lymphoid tissue immune recovery.

Hepatic safety of maraviroc in patients with HIV-1 and hepatitis C and/or B virus: 144-week results from a randomized, placebo-controlled trial

BACKGROUND

In the primary 48-week analysis of a hepatic safety trial in patients with HIV-1 coinfected with HBV and/or HCV, maraviroc-containing treatment regimens were not associated with increased hepatotoxicity.

METHODS

In this randomized, double-blind, placebo-controlled, multicentre study, patients received maraviroc twice daily (n=70) or placebo (n=67) with concomitant antiretroviral therapy for 144 weeks (Clinicaltrials.gov identifier, NCT01327547). The primary end point was the proportion of patients with protocol-defined Grade 3/4 alanine aminotransferase (ALT) abnormalities through week 48. Key secondary end points included 144-week analysis of Grade 3/4 ALT abnormalities and liver fibrosis by enhanced liver fibrosis (ELF) testing, hepatic elastography and an optional biopsy substudy.

RESULTS

Through 144 weeks of treatment, two (maraviroc) and three (placebo) patients met the protocol-defined Grade 3/4 ALT end point. Similar to the 48-week results, there were no statistically significant differences between groups in change from baseline in ELF or hepatic elastography. However, decreased elastography scores were noted in the maraviroc group. Blinded pathologist review suggested that 2 of 11 paired biopsies (both on maraviroc) showed signs of decreased fibrosis. One (maraviroc) and two (placebo) patients experienced treatment-related hepatobiliary adverse events (AEs). Five patients in the maraviroc group discontinued because of treatment-related AEs versus three in the placebo group. One death in the maraviroc group and two deaths in the placebo group were reported.

CONCLUSIONS

Use of maraviroc did not increase hepatotoxicity in this population through 144 weeks. Further investigation regarding possible beneficial effects of maraviroc on liver fibrosis may be warranted.

Inflammation and Change in Body Weight With Antiretroviral Therapy Initiation in a Multinational Cohort of HIV-Infected Adults

BACKGROUND

Both wasting and obesity are associated with inflammation, but the extent to which body weight changes influence inflammation during human immunodeficiency virus infection is unknown.

METHODS

Among a random virologically suppressed participants of the Prospective Evaluation of Antiretrovirals in Resource-Limited Settings trial, inflammatory markers were measured at weeks 0, 24, and 48 after antiretroviral therapy (ART) initiation. Associations between both baseline and change in body mass index (BMI; calculated as the weight in kilograms divided by the height in meters squared) and changes in inflammation markers were assessed using random effects models.

RESULTS

Of 246 participants, 27% were overweight/obese (BMI, ≥ 25), and 8% were underweight (BMI < 18.5) at baseline. After 48 weeks, 37% were overweight/obese, and 3% were underweight. While level of many inflammatory markers decreased 48 weeks after ART initiation in the overall group, the decrease in C-reactive protein (CRP) level was smaller in overweight/obese participants (P = .01), and the decreases in both CRP (P = .01) and interleukin 18 (P = .02) levels were smaller in underweight participants. Each 1-unit gain in BMI among overweight/obese participants was associated with a 0.02-log10 increase in soluble CD14 level (P = .05), while each 1-unit BMI gain among underweight participants was associated with a 9.32-mg/L decrease in CRP level (P = .001).

CONCLUSIONS

Being either overweight or underweight at ART initiation was associated with heightened systemic inflammation. While weight gain among overweight/obese persons predicted increased inflammation, weight gain among underweight persons predicted reduced inflammation.

Peginterferon α-2a for the treatment of HIV infection

INTRODUCTION

Novel approaches are urgently needed to achieve the next level of control of HIV infection beyond antiretroviral medications that will lead to the ultimate goal of curing HIV infection. Exploiting the innate immune system control of HIV is one possible component of that strategy with pegylated interferon α representing a well-characterized agent that is being applied to this effort.

AREAS COVERED

In this review, the authors summarize the history of interferon α treatment in the setting of HIV infection with a focus on clinical trials that examined the downstream effects on innate immune responses. More recently, clinical trials that administered pegylated interferon α-2a have demonstrated which interferon-stimulated genes are associated with its antiviral effects and which of these host-restriction factors may play a role in limiting the magnitude of the HIV reservoir.

EXPERT OPINION

The potential to exploit interferon α as part of a cure strategy is provocative. Whether key interferon-induced antiviral factors can be upregulated sufficiently to affect the reservoir is unknown. Additional research employing pegylated interferon α-2a is needed to identify which innate immune pathways are candidate targets for novel biological therapies for the potential cure of HIV infection.

Differential Specificity of Interferon-alpha Inducible Gene Expression in Association with Human Immunodeficiency Virus and Hepatitis C Virus Levels and Declines in vivo

OBJECTIVE

This study was aimed to correlate in vivo interferon (IFN) inducible gene (IFIG) expression and IFIG induction with viral-load (VL) and VL-kinetics of Human-Immunodeficiency-Virus (HIV) or Hepatitis-C-Virus (HCV) in HIV-positive patients treated with pegylated IFN-alpha-2a (PegIFNα).

METHODS

HIV mono-infected patients (N=8) and HIV/HCV co-infected patients (N=23, without HIV-viremia) were treated with PegIFNα (180 μg/week) for 12 and 48 weeks, respectively. Blood sampling for monitoring IFIG expression occurred at day_0 and week_3, _6 and _12 for HIV mono-infected patients vs. only at day_0 and week_48 for HIV/HCV co-infected subjects. IFIG expression (N=20) was measured in peripheral blood mononuclear cells by bDNA-assay. VL levels/changes in plasma were analyzed for correlation with IFIG expression/induction at/between selected time points. Overall, P<0.05 was considered significant.

RESULTS

None of the 20 IFIG expression profiles at day_0 correlated significantly with HIV-VL at day_0. Expression at day_0 of 3 IFIG (APOBEC3G/OAS1/OAS2) correlated significantly (r>+0.42/P<0.05) with HCV-VL at day_0. The strongest antiviral effect [measured as median viral decline per week: ΔVL/week (log10)] occurred in common against HIV and HCV between day_0 and week_3 during 12 weeks of continuous PegIFNα treatment in both cohorts. Expression at day_0 of 1 IFIG (APOBEC3A) correlated significantly (r<-0.71/P<0.05) with HIV-ΔVL/week (log10) from day_0 to week_3. No significance was reached in correlations between expression values of 20 IFIG at day_0 and HCV-ΔVL/week (log10) from day_0 to week_3. No significant correlation was detected between IFIG expression changes (ΔIFIG=induction) from day_0 to week_3 and HIV-ΔVL/week (log10) from day_0 to week_3. Interestingly, induction of 1 IFIG (ΔISG20) from day_0 to week_48 was significantly associated (P<0.05) with permanent HCV clearance.

CONCLUSION

This study demonstrates the differential specificity of PegIFNα mediated molecular actions by dissecting the kinetics of IFIG expression and induction, suggesting multiple, possibly non-overlapping mechanisms for antiviral effects against HCV and HIV.

Clinical and immunologic predictors of death after an acute opportunistic infection: results from ACTG A5164

BACKGROUND

In the pre-antiretroviral therapy (ART) era, markers of increased disease severity during an acute opportunistic infection (OI) were associated with mortality. Even with ART, mortality remains high during the first year after an OI in persons with advanced HIV infection, but it is unclear whether previous predictors of mortality remain valid in the current era.

OBJECTIVE

To determine clinical and immunological predictors of death after an OI.

METHODS

We used clinical data and stored plasma from ACTG A5164, a multicenter study evaluating the optimal timing of ART during a nontuberculous OI. We developed Cox models evaluating associations between clinical parameters and plasma marker levels at entry and time to death over the first 48 weeks after the diagnosis of OI. We developed multivariable models incorporating only clinical parameters, only plasma marker levels, or both.

RESULTS

The median CD4+ T-cell count in study participants at baseline was 29 cells/µL. Sixty-four percent of subjects had Pneumocystis jirovecii pneumonia (PCP). Twenty-three of 282 (8.2%) subjects died. In univariate analyses, entry mycobacterial infection, OI number, hospitalization, low albumin, low hemoglobin, lower CD4, and higher IL-8 and sTNFrII levels and lower IL-17 levels were associated with mortality. In the combined model using both clinical and immunologic parameters, the presence of an entry mycobacterial infection and higher sTNFrII levels were significantly associated with death.

CONCLUSIONS

In the ART era, clinical risk factors for death previously identified in the pre-ART era remain predictive. Additionally, activation of the innate immune system is associated with an increased risk of death following an acute OI.

Safety and efficacy of the peptide-based therapeutic vaccine for HIV-1, Vacc-4x: a phase 2 randomised, double-blind, placebo-controlled trial

BACKGROUND

Present combination antiretroviral therapy (cART) alone does not cure HIV infection and requires lifelong drug treatment. The potential role of HIV therapeutic vaccines as part of an HIV cure is under consideration. Our aim was to assess the efficacy, safety, and immunogenicity of Vacc-4x, a peptide-based HIV-1 therapeutic vaccine targeting conserved domains on p24(Gag), in adults infected with HIV-1.

METHODS

Between July, 2008, and June, 2010, we did a multinational double-blind, randomised, phase 2 study comparing Vacc-4x with placebo. Participants were adults infected with HIV-1 who were aged 18-55 years and virologically suppressed on cART (viral load <50 copies per mL) with CD4 cell counts of 400 × 10(6) cells per L or greater. The trial was done at 18 sites in Germany, Italy, Spain, the UK, and the USA. Participants were randomly assigned (2:1) to Vacc-4x or placebo. Group allocation was masked from participants and investigators. Four primary immunisations, weekly for 4 weeks, containing Vacc-4x (or placebo) were given intradermally after administration of adjuvant. Booster immunisations were given at weeks 16 and 18. At week 28, cART was interrupted for up to 24 weeks. The coprimary endpoints were cART resumption and changes in CD4 counts during treatment interruption. Analyses were by modified intention to treat: all participants who received one intervention. Furthermore, safety, viral load, and immunogenicity (as measured by ELISPOT and proliferation assays) were assessed. The 52 week follow-up period was completed in June, 2011. For the coprimary endpoints the proportion of participants who met the criteria for cART resumption was analysed with a logistic regression model with the treatment effect being assessed in a model including country as a covariate. This study is registered with ClinicalTrials.gov, number NCT00659789.

FINDINGS

174 individuals were screened; because of slow recruitment, enrolment stopped with 136 of a planned 345 participants and 93 were randomly assigned to receive Vacc-4x and 43 to receive placebo. There were no differences between the two groups for the primary efficacy endpoints in those participants who stopped cART at week 28. Of the participants who resumed cART, 30 (34%) were in the Vacc-4x group and 11 (29%) in the placebo group, and percentage changes in CD4 counts were not significant (mean treatment difference -5·71, 95% CI -13·01 to 1·59). However, a significant difference in viral load was noted for the Vacc-4x group both at week 48 (median 23,100 copies per mL Vacc-4x vs 71,800 copies per mL placebo; p=0·025) and week 52 (median 19,550 copies per mL vs 51,000 copies per mL; p=0·041). One serious adverse event, exacerbation of multiple sclerosis, was reported as possibly related to study treatment. Vacc-4x was immunogenic, inducing proliferative responses in both CD4 and CD8 T-cell populations.

INTERPRETATION

The proportion of participants resuming cART before end of study and change in CD4 counts during the treatment interruption showed no benefit of vaccination. Vacc-4x was safe, well tolerated, immunogenic, seemed to contribute to a viral-load setpoint reduction after cART interruption, and might be worth consideration in future HIV-cure investigative strategies.

FUNDING

Norwegian Research Council GLOBVAC Program and Bionor Pharma ASA.

Oral serum-derived bovine immunoglobulin improves duodenal immune reconstitution and absorption function in patients with HIV enteropathy

OBJECTIVES

To examine the impact of serum-derived bovine immunoglobulin, an oral medical food known to neutralize bacterial antigen and reduce intestinal inflammation, on restoration of mucosal immunity and gastrointestinal function in individuals with HIV enteropathy.

DESIGN

Open-label trial with intensive 8-week phase of bovine serum immunoglobulin (SBI) 2.5 g twice daily with a 4-week washout period and an optional 9-month extension study.

METHODS

HIV enteropathy was defined as chronic gastrointestinal symptoms including frequent loose or watery stools despite no identifiable, reversible cause. Upper endoscopy for tissue immunofluorescent antibody assay and disaccharide gut permeability/absorption studies were performed before and after 8 weeks of SBI to test mucosal immunity and gastrointestinal function. Blood was collected for markers of microbial translocation, inflammation, and collagen kinetics. A validated gastrointestinal questionnaire assessed changes in symptoms.

RESULTS

All eight participants experienced profound improvement in symptoms with reduced bowel movements/day (P = 0.008) and improvements in stool consistency (P = 0.008). Gut permeability was normal before and after the intervention, but D-xylose absorption increased in seven of eight participants. Mucosal CD4 lymphocyte densities increased by a median of 139.5 cells/mm2 from 213 to 322 cells/mm2 (P = 0.016). Intestinal-fatty acid binding protein (I-FABP), a marker of enterocyte damage, initially rose in seven of eight participants after 8 weeks (P = 0.039), and then fell below baseline in four of five who continued receiving SBI (P = 0.12). Baseline serum I-FABP levels were negatively correlated with subsequent rise in mucosal CD4 lymphocyte densities (r = -0.74, P = 0.046).

CONCLUSION

SBI significantly increases intestinal mucosal CD4 lymphocyte counts, improves duodenal function, and showed evidence of promoting intestinal repair in the setting of HIV enteropathy.

HIV disease activity as a modulator of lipoprotein(a) and allele-specific apolipoprotein(a) levels

OBJECTIVE

Mechanisms underlying the cardiovascular risk of lipoprotein(a) are poorly understood. We investigated the relationship of apolipoprotein(a) (apo(a)) size, lipoprotein(a), and allele-specific apo(a) levels with HIV disease activity parameters in a biethnic population.

METHODS AND RESULTS

Lipoprotein(a) and allele-specific apo(a) levels were determined in 139 white and 168 black HIV-positive patients. Plasma HIV RNA viral load and CD4+ T-cell count were used as surrogates for disease activity. Lipoprotein(a) and allele-specific apo(a) levels were higher in blacks than whites (for both P<0.001). Apo(a) allele size distribution was similar between the 2 ethnic groups, with a median apo(a) size of 28 kringle 4 repeats. Allele-specific apo(a) levels were positively associated with CD4+ T-cell count (P=0.027) and negatively with plasma HIV RNA viral load (P<0.001). Further, allele-specific apo(a) levels associated with smaller (<28 kringle 4) atherogenic apo(a) sizes were higher in subjects with CD4+ T-cell counts of ≥350 (P=0.002).

CONCLUSIONS

Allele-specific apo(a) levels were higher in subjects with high CD4+ T-cell count or low plasma HIV RNA viral load. The findings suggest that HIV disease activity reduced allele-specific apo(a) levels. Higher allele-specific apo(a) levels associated with atherogenic small apo(a) sizes might contribute to increased cardiovascular risk in HIV-positive subjects with improved disease status.

Elevated interleukin 8 and T-helper 1 and T-helper 17 cytokine levels prior to antiretroviral therapy in participants who developed immune reconstitution inflammatory syndrome during ACTG A5164

BACKGROUND

Immune reconstitution inflammatory syndrome (IRIS) reflects an aberrant immune response that can develop in human immunodeficiency virus-infected patients initiating antiretroviral therapy (ART). Its pathogenesis remains unclear.

METHODS

We performed a nested case-control study using specimens from ACTG A5164. We compared plasma biomarkers and T-cell subsets in 19 IRIS and 39 control participants at study entry, ART initiation, and IRIS and used conditional logistic regression to develop IRIS predictive models. We evaluated the effect of corticosteroids on biomarker levels.

RESULTS

Eleven and 8 participants developed paradoxical and unmasking IRIS, respectively, none while still receiving corticosteroids. Compared to controls, cases displayed elevations at study entry in interleukin (IL) 8, T-helper (Th) 1 (IL-2, interferon [IFN]-γ, tumor necrosis factor [TNF]) and Th17 (IL-17) cytokine levels that persisted through ART initiation and IRIS. In logistic regression, baseline higher IFN-γ and TNF were strong predictors of IRIS. Participants who received corticosteroids and later developed IRIS had marked increases in IL-6, IL-8, and IFN-γ at the time of IRIS. T-cell activation markers did not differ in cases and controls prior to ART but were increased in cases at the time of IRIS.

CONCLUSIONS

Increased IL-8, Th1, and Th17 cytokine levels in IRIS patients precede ART initiation and could help identify patient populations at higher risk for IRIS.

Quantitation of hepatitis C virus RNA in peripheral blood mononuclear cells in HCV-monoinfection and HIV/HCV-coinfection

Peripheral blood mononuclear cells (PBMCs) represent an extrahepatic hepatitis C virus (HCV) reservoir, the significance of which is unclear due to limited studies and varying test methodologies. In this study, a commercial viral load assay for measuring cell-associated PBMC HCV RNA was evaluated. HCV RNA was extracted from PBMCs, sorted CD14+, and CD19+ cells and corresponding plasma samples using the Abbott m2000 and Real-Time HCV assay. Test performance and influence of HIV seropositivity on plasma and PBMC HCV RNA were studied. Among 51 patients, 67 and 62 unique patient samples had detectable plasma and PBMC HCV viral load, respectively. The median PBMC viral load was 535 IU/1 M cells (range 29-5,190). CD19+ cells had significantly higher viral load than CD14+ cells (median log(10) HCV viral load 2.63 vs. 1.50 IU/ml; P< 0.001). Stability of PBMC viral load over time was demonstrated in untreated patients; all patients with an undetectable plasma HCV viral load after HCV treatment also demonstrated undetectable PBMC viral load. Repeated testing in nine samples yielded consistent PBMC viral load, differing by only 1.3-fold (range 1.0-1.7-fold). Among samples with detectable plasma HCV RNA, the correlation between PBMC and plasma viral load was moderate (r = 0.66) and was greater among HCV mono-infected compared to HIV/HCV co-infected subjects (r = 0.80 vs. 0.52). Measurement of cell-associated PBMC HCV RNA using a commercial assay demonstrated promising test characteristics. Differences in PBMC HCV viral load based on HIV-coinfection status and the significance of greater copy number in B-cells requires further study.

Host gene expression changes correlating with anti-HIV-1 effects in human subjects after treatment with peginterferon Alfa-2a

We investigated whether interferon-inducible genes (IFIGs) with known anti-human immunodeficiency virus (HIV) activity in vitro were associated with in vivo virological response in HIV infection. Nine untreated HIV-1-infected volunteers were treated for 12 weeks with peginterferon alfa-2a. A subset of IFIGs (23 of 47) increased compared with baseline through 6 weeks beyond therapy, and 10 of the 23 IFIGs significantly inversely correlated (r = -0.7; P < .05) with virological response. The strength of peginterferon alfa-2a-induced IFIG response significantly correlated with declines in HIV load during treatment (r(2) = 0.87, p = .003). This study links HIV virological response to a specific IFIG subset, a potential prognostic indicator in peginterferon alfa-2a-treated patients with HIV infection.

Lessons from maraviroc clinical trials

Evaluation of: Gulick RM, Lalezari J, Goodrich J et al. Maraviroc for previously treated patients with R5 HIV-1 infection. N. Engl. J. Med. 359, 1429-1441 (2008). Maraviroc is the first commercially available HIV chemokine receptor antagonist targeting HIV that utilizes the CCR5 chemokine receptor (R5 tropic). The Maraviroc versus Optimized Therapy in Viremic Antiretroviral Treatment-Experienced Patients (MOTIVATE) trials were two randomized, placebo-controlled studies designed to demonstrate the activity of maraviroc in triple-class-experienced HIV individuals, with a primary end point of viral load suppression at 48 weeks. Maraviroc outperformed the placebo plus optimized background (OBT) arm, and exhibited a favorable safety profile with low discontinuation rates, which equaled those of the placebo plus OBT group. The results of these trials led to maraviroc receiving regulatory approval for the treatment of HIV.

Safety, tolerability, and mechanisms of antiretroviral activity of pegylated interferon Alfa-2a in HIV-1-monoinfected participants: a phase II clinical trial

BACKGROUND

To our knowledge, the antiviral activity of pegylated interferon alfa-2a has not been studied in participants with untreated human immunodeficiency virus type 1 (HIV-1) infection but without chronic hepatitis C virus (HCV) infection.

METHODS

Untreated HIV-1-infected volunteers without HCV infection received 180 microg of pegylated interferon alfa-2a weekly for 12 weeks. Changes in plasma HIV-1 RNA load, CD4(+) T cell counts, pharmacokinetics, pharmacodynamic measurements of 2',5'-oligoadenylate synthetase (OAS) activity, and induction levels of interferon-inducible genes (IFIGs) were measured. Nonparametric statistical analysis was performed.

RESULTS

Eleven participants completed 12 weeks of therapy. The median plasma viral load decrease and change in CD4(+) T cell counts at week 12 were 0.61 log(10) copies/mL (90% confidence interval [CI], 0.20-1.18 log(10) copies/mL) and -44 cells/microL (90% CI, -95 to 85 cells/microL), respectively. There was no correlation between plasma viral load decreases and concurrent pegylated interferon plasma concentrations. However, participants with larger increases in OAS level exhibited greater decreases in plasma viral load at weeks 1 and 2 (r = -0.75 [90% CI, -0.93 to -0.28] and r = -0.61 [90% CI, -0.87 to -0.09], respectively; estimated Spearman rank correlation). Participants with higher baseline IFIG levels had smaller week 12 decreases in plasma viral load (0.66 log(10) copies/mL [90% CI, 0.06-0.91 log(10) copies/mL]), whereas those with larger IFIG induction levels exhibited larger decreases in plasma viral load (-0.74 log(10) copies/mL [90% CI, -0.93 to -0.21 log(10) copies/mL]).

CONCLUSION

Pegylated interferon alfa-2a was well tolerated and exhibited statistically significant anti-HIV-1 activity in HIV-1-monoinfected patients. The anti-HIV-1 effect correlated with OAS protein levels (weeks 1 and 2) and IFIG induction levels (week 12) but not with pegylated interferon concentrations.

Comparative cell-mediated immunogenicity of DNA/DNA, DNA/adenovirus type 5 (Ad5), or Ad5/Ad5 HIV-1 clade B gag vaccine prime-boost regimens

BACKGROUND

We report composite results from the Merck phase I program of near-consensus clade B human immunodeficiency virus (HIV) type 1 gag vaccines.

METHODS

Healthy HIV-uninfected adults were enrolled in 6 blinded placebo-controlled studies evaluating the immunogenicity of (1) a 4-dose regimen of a DNA vaccine, (2) a 3-dose priming regimen of the DNA vaccine with a booster dose of an adenovirus type 5 (Ad5)-vectored vaccine, or (3) a 3-dose regimen of the Ad5 vaccine. The DNA plasmid was provided with or without an aluminum phosphate or CRL1005 adjuvant. The primary end point was the unfractionated HIV-1 gag-specific interferon gamma enzyme-linked immunospot (ELISpot) response 4 weeks after the final dose.

RESULTS

Overall, 254 (83%) of 307 subjects randomized to the vaccine groups were evaluable. Adjuvants did not enhance immunogenicity of the DNA vaccine. Postboost ELISpot responder frequencies were higher for Ad5-containing regimens than for the DNA/DNA regimen (33%) but were similar for DNA/Ad5 (55%) and Ad5/Ad5 (50%). DNA/DNA elicited mainly a CD4 response, whereas Ad5/Ad5 elicited mainly a CD8 response; DNA/Ad5 generated CD4 and CD8 responses comparable to those of DNA/DNA and Ad5/Ad5, respectively.

CONCLUSIONS

The DNA vaccine alone or as a priming regimen for the Ad5 vaccine did not increase unfractionated ELISpot responses compared with the Ad5 vaccine alone. Qualitative T cell responses to different vaccine regimens deserve further study.

Low sensitivity of T-cell based detection of tuberculosis among HIV co-infected Tanzanian in-patients

OBJECTIVE

To evaluate the performance of QuantiFERON-TB GOLD (QFTG) in a resource-poor setting among patients with and without HIV infection.

DESIGN

Cross-sectional study.

SETTING

Two hospitals in Northern Tanzania.

SUBJECTS

Eighty three adult male and female inpatients.

INTERVENTION

All patients were screened for HIV infection and underwent tuberculin skin test (TST) and QFTG.

RESULTS

Eighty-three subjects were enrolled, and 29 (35%) of 83 were HIV-infected. QFTG yielded indeterminate results in 12 (22%; 95% CI 12%-34%) of 54 HIV-uninfected and 13 (45%; 95% CI 26%-64%) of 29 HIV-infected subjects (p = 0.0323). Among those with smear-positive pulmonary tuberculosis, TST was positive in 40 (100%; 95% CI 91%-100%) of 40 HIV-uninfected subjects compared with seven (54%; 95% CI 25%-81%) of 13 HIV-infected subjects (p < 0.0001), and QFTG was positive in 28 (70%; 95% CI 53%-83%) of 40 HIV-uninfected subjects compared with three (23%; 95% CI 5%-54%) of 13 HIV-infected subjects (p = 0.0029). Among medical inpatients at risk for latent tuberculosis infection, TST was positive in seven (50%) of 14 HIV-uninfected patients and three (19%) of 16 HIV-infected patients (p = 0.0701) and QFTG was positive among two (14%) of 14 HIV-uninfected patients and three (19%) of 16 HIV-infected patients (p = 0.7437).

CONCLUSIONS

The presence of HIV co-infection was associated with a significant reduction in sensitivity of both the TST (p < 0.0001) and QFTG (p = 0.0029) for the diagnosis of active M. tuberculosis infection. The high proportion of indeterminate QFTG and lack of sensitivity, particularly among HIV-infected patients, may limit its applicability in settings like Tanzania. Larger studies in resource-poor settings are required.

IL-7 administration drives T cell-cycle entry and expansion in HIV-1 infection

Interleukin 7 (IL-7) is a common gamma chain receptor cytokine implicated in thymopoiesis and in peripheral expansion and survival of T lymphocytes. The safety and activity of recombinant human IL-7 (rhIL-7) administration were therefore examined in HIV-infected persons. In this prospective randomized placebo-controlled study, a single subcutaneous dose of rhIL-7 was well tolerated with biologic activity demonstrable at 3 microg/kg and a maximum tolerated dose of 30 microg/kg. Injection site reactions and transient elevations of liver function tests were the most notable side effects. Transient increases in plasma HIV-RNA levels were observed in 6 of 11 IL-7-treated patients. Recombinant hIL-7 induced CD4 and CD8 T cells to enter cell cycle; cell-cycle entry was also confirmed in antigen-specific CD8 T cells. Administration of rhIL-7 led to transient down-regulation of the IL-7 receptor alpha chain (CD127) in both CD4(+) and CD8(+) T cells. Single-dose rhIL-7 increased the numbers of circulating CD4(+) and CD8(+) T cells, predominantly of central memory phenotype. The frequency of CD4(+) T cells with a regulatory T-cell phenotype (CD25(high) CD127(low)) did not change after rhIL-7 administration. Thus, rhIL-7 has a biologic and toxicity profile suggesting a potential for therapeutic trials in HIV infection and other settings of lymphopenia. This clinical trial has been registered at http://www.clinicaltrials.gov under NCT0099671.

Quantitative 3D video microscopy of HIV transfer across T cell virological synapses

The spread of HIV between immune cells is greatly enhanced by cell-cell adhesions called virological synapses, although the underlying mechanisms have been unclear. With use of an infectious, fluorescent clone of HIV, we tracked the movement of Gag in live CD4 T cells and captured the direct translocation of HIV across the virological synapse. Quantitative, high-speed three-dimensional (3D) video microscopy revealed the rapid formation of micrometer-sized "buttons" containing oligomerized viral Gag protein. Electron microscopy showed that these buttons were packed with budding viral crescents. Viral transfer events were observed to form virus-laden internal compartments within target cells. Continuous time-lapse monitoring showed preferential infection through synapses. Thus, HIV dissemination may be enhanced by virological synapse-mediated cell adhesion coupled to viral endocytosis.

Incomplete reconstitution of T cell subsets on combination antiretroviral therapy in the AIDS Clinical Trials Group protocol 384

BACKGROUND

Initiation of combination antiretroviral therapy (ART) results in higher total CD4 cell counts, a surrogate for immune reconstitution. Whether the baseline CD4 cell count affects reconstitution of immune cell subsets has not been well characterized.

METHODS

Using data from 978 patients (621 with comprehensive immunological assessments) from the AIDS [Acquired Immunodeficiency Syndrome] Clinical Trials Group protocol 384, a randomized trial of initial ART, we compared reconstitution of CD4(+), CD4(+) naive and memory, CD4(+) activation, CD8(+), CD8(+) activation, B, and natural killer cells among patients in different baseline CD4(+) strata. Reference ranges for T cell populations in control patients negative for human immunodeficiency virus (HIV) infection were calculated using data from AIDS Clinical Trials Group protocol A5113.

RESULTS

Patients in the lower baseline CD4(+) strata did not achieve total CD4(+) cell counts similar to those of patients in the higher strata during 144 weeks of ART, although CD4(+) cell count increases were similar. Ratios of CD4(+) naive-memory cell counts and CD4(+):CD8(+) cell counts remained significantly reduced in patients with lower baseline CD4(+) cell counts (

CONCLUSIONS

After nearly 3 years of ART, T cell subsets in patients with baseline CD4(+) cell counts >350 cells/mm(3) achieved or approached the reference range those of control individuals without HIV infection. In contrast, patients who began ART with Collapse

Key Words Collapse

MESH Headings

• Acquired Immunodeficiency Syndrome/drug therapy
• Acquired Immunodeficiency Syndrome/immunology
• Adult
• Antiretroviral Therapy, Highly Active
• B-Lymphocytes/immunology
• CD4 Lymphocyte Count
• CD4-CD8 Ratio
• Female
• Humans
• Killer Cells, Natural/immunology
• Male
• Middle Aged
• T-Lymphocyte Subsets/immunology

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Grants

• AI25879 NIAID NIH HHS
• AI066992 NIAID NIH HHS
• K01 AI062435-02 NIAID NIH HHS
• R01 AI066992 NIAID NIH HHS
• U01 AI038858 NIAID NIH HHS
• AI27659 NIAID NIH HHS
• AI38855 NIAID NIH HHS
• IP30AI060354 NIAID NIH HHS
• U01 AI025879 NIAID NIH HHS
• K01 AI062435 NIAID NIH HHS
• AI27666 NIAID NIH HHS
• AI38858 NIAID NIH HHS
• K01 AI062435-04 NIAID NIH HHS
• U01 AI038855 NIAID NIH HHS
• K01 AI062435-03 NIAID NIH HHS
• K01AI062435 NIAID NIH HHS
• U01 AI027666 NIAID NIH HHS
• K01 AI062435-01A1 NIAID NIH HHS
• U01 AI027659 NIAID NIH HHS
• P30 AI060354 NIAID NIH HHS

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Affiliation(s)

Gregory K Robbins Infectious Diseases Unit, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114, USA.
John G Spritzler
Ellen S Chan
David M Asmuth
Rajesh T Gandhi
Benigno A Rodriguez
Gail Skowron
Paul R Skolnik
Robert W Shafer
Richard B Pollard

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Pegylated interferon-alpha 2a treatment of chronic SIV-infected macaques

BACKGROUND

In vitro and clinical observations in HIV-infected patients receiving interferon alpha therapy have shown a reduction in HIV loads. Limited investigations have explored the innate or adaptive immune responses of IFN-alpha on SIV replication in vivo.

METHODS

Seven chronically infected rhesus macaques were given pegylated IFN-alpha 2a (n = four) or saline (n = three) injections once weekly for 14 weeks. Weekly peripheral blood samples were taken for safety parameters, viral load determinations, and measurements of innate and adaptive immune responses.

RESULTS

Pharmacokinetic measurements demonstrated therapeutic peg-IFN-alpha levels for the initial period of therapy and IFN-alpha inducible antiviral molecules were increased sporadically in the PBMC mRNA of the treatment group. Despite the demonstrable effect of the IFN-alpha injections, the treatment had no effect on plasma viral RNA levels.

CONCLUSIONS

This work demonstrates that while short term IFN-alpha therapy induces innate antiviral immunity, it does not dramatically enhance or suppress viral replication. However, studies in the SIV model to determine therapeutic potential of chronic IFN-alpha therapy for the treatment of HIV will require macaque specific cytokines.

Nine-color flow cytometry for accurate measurement of T cell subsets and cytokine responses. Part I: Panel design by an empiric approach

Polychromatic flow cytometry offers the unprecedented ability to investigate multiple antigens per cell. Unfortunately, unwanted spectral overlaps and compensation problems increase when more than four colors are used, but these problems can be minimized if staining combinations are chosen carefully. We used an empiric approach to design, test and identify six-color T cell immunophenotyping reagent panels that can be expanded to include three or more functional or other markers in the FITC, PE, and APC channels without significant spectral limitations. Thirty different six-color T cell surface antigen reagent panels were constructed to identify major T cell subsets and maturational subtypes as defined by CCR7 and CD45RA expression, while excluding monocytes, B and non-viable cells. Staining performance of each panel was compared on cryopreserved cells from a single healthy donor recorded on a multiparameter cell sorter. Ten of the thirty reagent panels offered reliable resolution of T cell major and maturational surface markers. Of these, two panels were selected that showed the least spectral overlap and resulting background increase in the FITC, PE, and APC channels. These channels were left unoccupied for inclusion of additional phenotypic or functional markers, such as cytokines. Careful reagent titration and testing of multiple candidate panels are necessary to ensure quality results in multiparametric measurements.

Evidence for calpain-mediated androgen receptor cleavage as a mechanism for androgen independence

Prostate carcinoma is the most commonly diagnosed cancer in men and the second leading cause of death due to cancer in Western civilization. Androgen ablation therapy is effective in treating androgen-dependent tumors, but eventually, androgen-independent tumors recur and are refractory to conventional chemotherapeutics. Hence, the emergence of androgen independence is the most challenging problem in managing prostate tumors. We report a novel mechanism of androgen independence: calpain cleaves the androgen receptor (AR) into an androgen-independent isoform. In vitro and in vivo analyses show that calpain removes the COOH-terminal ligand binding domain generating a constitutively active molecule. Analysis of human prostate tumors indicates that several tumors express higher levels of this truncated AR than noncancerous prostate tissue. In transient transfection studies, the truncated AR is three to five times more potent than the full-length receptor in transactivating transcription. The androgen-independent Rv1 cells express high levels of the truncated AR, and treatment of these cells with a calpain inhibitor reduces truncated AR expression. In the absence of androgen, inhibition of calpain activity induces apoptosis. The HIV protease inhibitor amprenavir inhibits calpain activity and is also effective in inducing apoptosis in the Rv1 cell line. The cell culture studies were reproduced in a mouse xenograft model, where, in the absence of androgens, amprenavir significantly reduces tumor growth. Together, these studies indicate that calpain-dependent proteolysis of the AR may be a mechanism of androgen independence. The calpain inhibition studies suggest that inhibiting this activity may be a potential treatment for some androgen-independent prostate tumors.

Correlates of epidermal nerve fiber densities in HIV-associated distal sensory polyneuropathy

OBJECTIVE

To demonstrate the relationship between epidermal nerve fiber density (ENFD) in the leg and the phenotype of HIV-associated distal sensory polyneuropathy (HIV-DSP) in a multicenter prospective study (ACTG A5117).

METHODS

A total of 101 HIV-infected adults, with CD4 cell count <300 cells/mm(3) and who had received antiretroviral therapy (ART) for at least 15 consecutive weeks, underwent standardized clinical and electrophysiologic assessment. All 101 subjects were biopsied at the distal leg (DL) and 99 at the proximal thigh (PT) at baseline. ENFD was assessed by skin biopsy using PGP9.5 immunostaining. Associations of ENFD with demographics, ART treatment, Total Neuropathy Score (TNS), sural sensory nerve action potential (SNAP) amplitude and conduction velocity, quantitative sensory testing (QST) measures, and neuropathic pain were explored.

RESULTS

ENFD at the DL site correlated with neuropathy severity as gauged by TNS (p < 0.01), the level of neuropathic pain quantified by the Gracely Pain Scale (GPS) (p = 0.01) and Visual Analogue Scale (VAS) (p = 0.01), sural SNAP amplitude (p < 0.01), and toe cooling (p < 0.01) and vibration (p = 0.02) detection thresholds. ENFD did not correlate with neurotoxic ART exposure, CD4 cell count, or plasma HIV-1 viral load.

CONCLUSIONS

In subjects with advanced HIV-1 infection, epidermal nerve fiber density (ENFD) assessment correlates with the clinical and electrophysiologic severity of distal sensory polyneuropathy (DSP). ENFD did not correlate with previously established risk factors for HIV-DSP, including CD4 cell count, plasma HIV-1 viral load, and neurotoxic antiretroviral therapy exposure.

Multifunctional human immunodeficiency virus (HIV) gag-specific CD8+ T-cell responses in rectal mucosa and peripheral blood mononuclear cells during chronic HIV type 1 infection

The intestinal tract is a lymphocyte-rich site that undergoes severe depletion of memory CD4(+) T cells within days of simian immunodeficiency virus or human immunodeficiency virus type 1 (HIV-1) infection. An ensuing influx of virus-specific CD8(+) T cells, which persist throughout the chronic phase of infection, has also been documented in the gastrointestinal tract. However, little is known of the functionality of these effector cells or their relationship to the disease course. In this study, we measured CD8(+) T-cell responses to HIV-1 peptides in paired rectal and blood samples from chronically infected patients. In both blood and rectum, there was an immunodominant CD8(+) T-cell response to HIV Gag compared to Pol and Env (P < 0.01). In contrast, cytomegalovirus pp65 peptides elicited gamma interferon (IFN-gamma) secretion strongly in peripheral blood mononuclear cells (PBMC) but weakly in rectal CD8(+) T cells (P = 0.015). Upon stimulation with HIV peptides, CD8(+) T cells from both sites were capable of mounting complex responses including degranulation (CD107 expression) and IFN-gamma and tumor necrosis factor alpha (TNF-alpha) production. In rectal tissue, CD107 release was frequently coupled with production of IFN-gamma or TNF-alpha. In patients not on antiretroviral therapy, the magnitude of Gag-specific responses, as a percentage of CD8(+) T cells, was greater in the rectal mucosa than in PBMC (P = 0.054); however, the breakdown of responding cells into specific functional categories was similar in both sites. These findings demonstrate that rectal CD8(+) T cells are capable of robust and varied HIV-1-specific responses and therefore likely play an active role in eliminating infected cells during chronic infection.

Effect of baseline- and treatment-related factors on immunologic recovery after initiation of antiretroviral therapy in HIV-1-positive subjects: results from ACTG 384

OBJECTIVE

To assess the effect of baseline- and treatment-related factors on immunologic recovery after initiation of antiretroviral therapy (ART).

METHODS

Nine hundred eighty antiretroviral-naive HIV-1+ subjects were randomized to start stavudine/didanosine or zidovudine/lamivudine with nelfinavir, efavirenz, or both nelfinavir and efavirenz.

RESULTS

Greater CD4 cell recovery was associated with age of 40 years or younger, female sex, higher baseline naive/memory CD4 cell ratio, higher baseline virus load (VL), and virologic suppression (VS). Most subjects who maintained an undetectable VL had a substantial increase in CD4 cell count, but 13% of the subjects did not, even after 3 years of VS. Persistent T-cell activation was associated with lower CD4 cell recovery, even in subjects who achieved VS. Initial treatment assignment did not affect total CD4 cell recovery, naive/memory CD4 cell reconstitution, or decline in T-cell activation. In addition to CD4 cell recovery, B-cell counts rose substantially after ART initiation.

CONCLUSIONS

In this large randomized trial, younger age, female sex, higher naive/memory CD4 cell ratio, higher baseline VL, and VS were associated with greater CD4 cell increase, whereas persistent T-cell activation was associated with impaired CD4 cell recovery after ART initiation. Initial treatment assignment did not affect CD4 cell reconstitution.

HIV neuropathy natural history cohort study: assessment measures and risk factors

BACKGROUND

Distal sensory polyneuropathy (DSP) is the most common neurologic complication of human immunodeficiency virus (HIV) infection. Risk factors for DSP have not been adequately defined in the era of highly active antiretroviral therapy.

METHODS

The authors evaluated 101 subjects with advanced HIV infection over 48 weeks. Assessments included a brief peripheral neuropathy (PN) screen (BPNS), neurologic examination, nerve conduction studies, quantitative sensory testing (QST), and skin biopsies with quantitation of epidermal nerve fiber density. Data were summed into a Total Neuropathy Score (TNS). The presence, severity, and progression of DSP were related to clinical and laboratory results.

RESULTS

The mean TNS (range 0 to 36) was 8.9, with 38% of subjects classified as PN-free, 10% classified as having asymptomatic DSP, and 52% classified as having symptomatic DSP. Progression in TNS from baseline to week 48 occurred only in the PN-free group at baseline (mean TNS change = 1.16 +/- 2.76, p = 0.03). Factors associated with progression in TNS were lower current TNS, distal epidermal denervation, and white race. As compared with the TNS diagnosis of PN at baseline, the BPNS had a sensitivity of 34.9% and a specificity of 89.5%.

CONCLUSIONS

In this cohort of advanced human immunodeficiency virus (HIV)-infected subjects, distal sensory polyneuropathy was common and relatively stable over 48 weeks. Previously established risk factors, including CD4 cell count, plasma HIV RNA, and use of dideoxynucleoside antiretrovirals were not predictive of the progression of distal sensory polyneuropathy (DSP). Distal epidermal denervation was associated with worsening of DSP. As compared with the Total Neuropathy Score, the brief peripheral neuropathy screen had relatively low sensitivity and high specificity for the diagnosis of DSP.

Cell cycle kinetic dysregulation in HIV-infected normal lymphocytes

BACKGROUND

Viruses alter cellular gene transcription and protein binding at many steps critical for cell cycle regulation to optimize the milieu for productive infection. Reasoning that virus-host cell interactions would result in perturbations of cell cycle kinetics, measurement of the duration of the phases of the cell cycle in normal T lymphocytes infected with human immunodeficiency virus (HIV) was undertaken.

METHODS

Flow cytometric measurement of bromodeoxyuridine-labeled and DNA content-stained cells at multiple points through the cell cycle allowed estimation of the fraction of cells in each phase, the potential doubling-time, and the durations of S and G(2)/M phases. Separate analysis of the HIV(+) and HIV(-) populations within the infected cultures was performed based on intracellular, anti-HIV core p24 antibody labeling. A novel mathematical model, which accounted for cell loss, was developed to estimate cell cycle phases.

RESULTS

(a) S phase was prolonged in the HIV-1(SF2)-infected cells compared with control. (b) This delay in S phase was due to delay in the population of cells not expressing HIV-1 antigens (p24 negative). (c) Accumulation of cells in G(2)/M phase was confirmed in HIV-1-infected cultures and was proportional to the level of infection as measured by p24 fluorescent intensity. However, all mock and HIV-1-infected populations predicted to proceed through cell division demonstrated similar G(2)/M-phase durations. (c) Potential doubling times were longer in the infected cultures; in contrast, the p24(+) subpopulations accounted for this delay. This suggests an isolated delay in the G(0)/G(1) phase for that population of cells.

CONCLUSIONS

Multiple phases of host cell cycle durations were affected by HIV-1(SF2) infection in this in vitro model, suggesting novel HIV-1 pathogenesis mechanisms. Prolonged S-phase durations in HIV-1 infected/p24(-) and G(0)/G(1)-phase durations in HIV-1 infected/p24(+) subpopulations require further study to identify mechanistic pathways.

E2F1 expression in LNCaP prostate cancer cells deregulates androgen dependent growth, suppresses differentiation, and enhances apoptosis

INTRODUCTION AND OBJECTIVES

To investigate the role of E2F/RB in androgen independent proliferation, differentiation, and sensitivity to apoptotic stimuli of LNCaP prostate cancer cells.

METHODS

The effects of E2F1 overexpression on androgen independent proliferation, differentiation, and apoptotic responses was assessed by flow cytometry, Western blot analysis and staining of nuclei.

RESULTS

Overexpression of E2F1 in LNCaP cells confers resistance to an androgen withdrawal-mediated growth arrest, prevents differentiation, and modifies apoptotic responses. Androgen independent proliferation is associated with a dose dependent elevation of cyclin E. Cells expressing high levels of E2F1 continue to express androgen receptor and have a diminished expression of neuronal specific enolase when cultured in androgen-depleted media. Additionally, E2F1-expressing cells are more sensitive to etoposide-induced apoptosis. Western blot analysis revealed that LNCaP-E2F1 cells have elevated expression of p73, Apaf-1, caspase-3, caspase-7, but expression of caspase-8 and -9, p14(ARF), and Mcl-1, is unaltered.

CONCLUSION

This is the first study that describes E2F1-dependent modifications of androgen dependence, differentiation, and sensitivity to apoptotic stimuli in LNCaP cells. Our analysis also identifies a subset of E2F1 targets that are instrumental in altering proliferative, differentiation, and apoptotic properties. Deregulation of the E2F/RB pathway and subsequent modification of key regulatory proteins may promote the development of hormone-refractory prostate tumors.

Estimating cell death in G2M using bivariate BrdUrd/DNA flow cytometry

BACKGROUND

In an accompanying paper (Asmuth et al.) it was found necessary to include cell death explicitly to estimate parameters of cell proliferation. The use of bivariate flow cytometry to estimate the phase durations and the doubling times of cells labeled with thymidine analogues is well established. However, these methods of analysis do not consider the possibility of cell death. This report demonstrates that estimating cell death in G(2)/M is possible.

METHODS

Mathematical models for the experimental quantities, the fraction of labeled undivided cells, the fraction of labeled divided cells, and the relative movement were developed. These models include the possibility that, of the cells with G(2)/M DNA content, only a certain fraction will divide, with the remainder dying after some time T(R). Simulation studies were conducted to test the possibility of using simple methods to estimate phase durations and cell death rates.

RESULTS

Cell death alters the estimates of phase transit times in a rather complex manner that depends on the lifetime of the doomed cells. However, it is still possible to obtain estimates of the phase durations of cells in S and G(2)/M and the death rates of cells in G(2)/M.

CONCLUSIONS

The methods presented herein provide a new way to characterize cell populations that includes cell death rates and common measurements of cell proliferation.

Hepatitis B and C viral load changes following initiation of highly active antiretroviral therapy (HAART) in patients with advanced HIV infection

Chronic infection with either hepatitis B (HBV) or hepatitis C virus (HCV) is frequently present in patients seropositive for human immunodeficiency virus (HIV) because of shared routes of transmission. With the advent of highly active antiretroviral therapy (HAART) regimens capable of controlling HIV replication and dramatically prolonging the survival of HIV-infected patients, the impact of co-morbid infections such as HBV and HCV has come into focus. Several studies have monitored HBV or HCV viral loads following initiation of HAART, with disparate results. The effects of HAART on hepatitis B and C plasma viral loads (n = 9 and 32, respectively) and on liver enzyme levels were studied in a large cohort of prospectively studied subjects with advanced stage HIV disease. Comparing the mean pre- and post-HAART levels, there was an estimated increase of (a) 1.40 log(10) from 4.83 to 6.24 log(10) for HBV plasma viral load (P = 0.07), (b) 0.74 log(10) from 6.38 to 7.12 log(10) for HCV plasma viral load (P = 0.001), and (c) 19.4 U/L from 37.4 to 56.8 U/L for serum alanine aminotransferase (P < 0.001). While the number of subjects co-infected with HIV and HBV was limited, these data collected in a population of advanced stage HIV-infected patients raises questions regarding the interactions of these viruses with each other and the host immune system and has implications regarding the order in which antiviral therapies are initiated.

A phase II, double-masked, randomized, placebo-controlled evaluation of a human monoclonal anti-Cytomegalovirus antibody (MSL-109) in combination with standard therapy versus standard therapy alone in the treatment of AIDS patients with Cytomegalovirus retinitis

ACTG 266 was designed as a randomized study to evaluate two doses of the human monoclonal antibody directed against CMV gH (MSL-109) versus placebo, each in combination with standard antiviral therapy for the treatment of newly diagnosed Cytomegalovirus (CMV) retinitis in AIDS patients. A total of 82 subjects were enrolled and received either placebo (n = 28), or MSL-109 at 15 mg (n = 26) or 60 mg (n = 28) every 2 weeks until disease progression was diagnosed. The primary endpoint, disease progression, was determined by masked reading of retinal photographs taken every 4 weeks read by a single investigator. The median time to progression was 8.0, 8.3, and 12.1 weeks in the placebo, MSL-109 15mg and MSL-109 60 mg cohorts, respectively (P = 0.087, placebo versus 60 mg cohort). There were 22 deaths during the study period (9, 9, and 4 in the placebo, MSL-109 15 mg and MSL-109 60 mg cohorts, respectively (P = 0.0058, placebo versus 60 mg cohort)). MSL-109 was well tolerated with no significant adverse events attributable to study medication. The unexplained survival advantage in the higher dose cohort was discordant with the findings of the parallel Studies of Ocular Complications of AIDS Research Group (SOCA)-Monoclonal Anti-CMV Retinitis Trial (MACRT), which was prematurely halted because of increased mortality in subjects treated with high-dose MSL-109, recognizing that A266 enrolled subjects with newly diagnosed, whereas the MACRT enrolled subjects with relapsed, CMV retinitis.

Treatments for hepatitis B

New optimism surrounds treatments for chronic hepatitis B (CHB). Interferon- alpha , lamivudine, and adefovir dipivoxil are currently approved by the United States Food and Drug Administration for the treatment of CHB. All 3 treatments possess unique characteristics with respect to their side effect profiles, potencies, and treatment niches within the spectrum of CHB. New agents, which are in various stages of clinical development, represent potential improvements within existing, as well as novel, classes of antiviral therapy, and they offer significant promise of a cure for the many patients with chronic and progressive hepatitis B. However, there remain many challenges in understanding the implications of drug resistance, the role of combination therapy, and how to define the response to therapy within subsets of patients with hepatitis B.

Hydroxyurea in combination with didanosine and stavudine in antiretroviral-experienced HIV-infected subjects with a review of the literature

The safety and efficacy of hydroxyurea with didanosine in combination with stavudine in nucleoside reverse-transcriptase inhibitor (NRTI)-experienced patients was investigated. Entry criteria included HIV-1 infected, NRTI-experienced adults, with CD4(+) counts 50-550 cells/mm(3) and viral loads >or=12,500 copies/mL. Subjects were treated with didanosine 200 mg twice a day (BID), stavudine 40 mg BID, and hydroxyurea 1000 mg daily for 16 weeks. Thirty-one HIV-1 subjects with mean bDNA viral load 1x10(5) log(10) copies/mL and mean CD4(+) T-cell counts of 231 cells/mm(3) were enrolled. A 1.3 log(10) decrease in mean viral load was seen at 12 weeks of therapy. Prior didanosine use resulted in a more rapid response to therapy compared with prior zidovudine use. Side effects consisting of neutropenia, pancreatitis, and peripheral neuropathy occurred in four subjects and resolved upon withdrawal of therapy. This non-randomized study in subjects with a mean CD4(+) T-cell count of 230 cells/mm(3) demonstrates the antiviral activity of hydroxyurea+didanosine and stavudine. Toxicities related to therapy need to be followed closely. The results support the need for a randomized, prospective study to determine the safety and efficacy of hydroxyurea plus didanosine in antiretroviral-experienced patients with CD4(+) cell counts below 300 cells/mm(3).

Absence of HBV and HCV, HTLV-I and -II, and human herpes virus-8 activation after allogeneic RBC transfusion in patients with advanced HIV-1 infection

BACKGROUND

The Viral Activation Transfusion Study was a prospective, randomized, double-blind comparison of transfusion with WBC-reduced versus non-WBC-reduced RBCs to HIV+ patients. The primary study characterized the effect of transfusion on HIV and CMV activation by monitoring viral load changes. The present study analyzed HBV, HCV, HTLV-I and -II, and human herpes virus-8 (HHV-8) viral load before and after transfusion to evaluate the further hypothesis that global immune stimulation following allogeneic RBC transfusion results in activation and increased viral proliferation of chronic viral infections other than HIV and CMV.

STUDY DESIGN AND METHODS

Baseline samples from 519 to 523 subjects were screened for HBV, HCV, HTLV-I and -II, and HHV-8 infection, and baseline, serial weekly, and quarterly blood samples from infected subjects in the non-WBC-reduced arm were evaluated for changes from baseline in viral nucleic acid and ALT levels.

RESULTS

Seroprevalence of HBV, HCV, HTLV-I and -II, and HHV-8 was 68, 25, 5, and 30 percent, respectively. No significant induction of HBV, HCV, HHV-8, or HTLV-I and -II viral replication following allogeneic transfusion of non-WBC-reduced blood was observed. A significant, albeit small, association was observed between transfusion and ALT.

CONCLUSIONS

Based on these results and our previous finding that no adverse effect on HIV and CMV viral load and disease progression results from allogeneic transfusion, no evidence is found to support the selective use of WBC-reduced blood components for HIV-infected patients.

Cytomegalovirus glycoprotein B groups in human immunodeficiency virus-infected patients with incident retinitis

Cytomegalovirus (CMV) strains may be categorized into 4 different groups on the basis of glycoprotein B (gB) genotype. gB genotypes in CMV polymerase chain reaction (PCR)-positive samples from case patients who were diagnosed with retinitis during prospective follow-up were compared with genotypes in CMV PCR-positive samples from an equal number of retinitis-free matched control subjects. All patients were infected with human immunodeficiency virus (HIV) and CMV. Control subjects and their plasma samples were matched with case patients according to baseline CD4(+) T cell count, transfusion history, HIV risk factor, and follow-up time. CMV DNA was genotyped by restriction-enzyme digestion. Eighteen patients met our case definition. Approximately one-third of patients had gB genotype 1, and half had gB genotype 2. These rates were similar among case patients and control subjects and were similar by risk group. The CMV gB2 genotype is not a major determinant of retinitis pathogenicity but appears to be highly prevalent among HIV-infected patients.

Leukocyte-reduced red blood cell transfusions in patients with anemia and human immunodeficiency virus infection: the Viral Activation Transfusion Study: a randomized controlled trial

CONTEXT

Allogeneic blood transfusions have immunomodulatory effects and have been associated with activation of human immunodeficiency virus (HIV) and cytomegalovirus (CMV) in vitro and of HIV in small pilot studies. Retrospective studies suggest that transfusions adversely affect the clinical course of HIV. Data in selected non-HIV-infected patients requiring blood transfusion have suggested clinical benefit with leukocyte-reduced red blood cells (RBCs).

OBJECTIVE

To compare the effects of leukoreduced and unmodified RBC transfusions on survival, complications of acquired immunodeficiency syndrome, and relevant laboratory markers in HIV-infected patients.

DESIGN AND SETTING

Double-blind randomized controlled trial conducted in 11 US academic medical centers from July 1995 through June 1999, with a median follow-up of 12 months (24 months in survivors).

PATIENTS

A total of 531 persons infected with HIV and CMV, aged 14 years or older, who required transfusions for anemia; 259 received leukoreduced transfusions and 262 received unmodified transfusions (10 did not receive the planned transfusion).

MAIN OUTCOME MEASURES

Survival and change in plasma HIV RNA level 7 days after transfusion, compared by type of transfusion.

RESULTS

At entry, the groups were similar in demographic, clinical, and relevant laboratory characteristics. A total of 3864 RBC units were transfused. Two hundred eighty-nine deaths occurred (151 with leukoreduced transfusion; 138 with unmodified transfusion); median survival was 13.0 and 20.5 months, respectively (relative hazard [RH], 1.20; 95% confidence interval [CI], 0.95-1.51; log-rank P =.12). Analyses adjusted for prognostic factors suggested possible worse survival with leukoreduction (RH, 1.35; 95% CI, 1.06-1.72). There was no difference in time to new opportunistic event/death or frequency of transfusion reactions. No changes in plasma HIV RNA level were seen in either group at days 7, 14, 21, or 28, even in patients not taking antiretroviral drugs. There were no differences in trends between groups in CMV DNA, CD4 cell counts, activated (CD38% or human leukocyte antigen-DR) CD8 cell counts, or plasma cytokine levels.

CONCLUSIONS

We found no evidence of HIV, CMV, or cytokine activation following blood transfusion in patients with advanced HIV infection. Leukoreduction provided no clinical benefit in these patients. These data demonstrate the importance of conducting controlled studies of effects of leukoreduction in different patient populations, since smaller studies in other patient populations have suggested leukoreduction may be beneficial.

Changing patterns of infections in patients with AIDS: a study of 279 autopsies of prison inmates and nonincarcerated patients at a university hospital in eastern Texas, 1984-1993

Reports on autopsies of 279 persons infected with human immunodeficiency virus (HIV) were reviewed retrospectively to determine changes in survival rates and infections and to identify differences between prison inmates and nonincarcerated patients. The 78 cases from 1984 through 1988 were compared with 201 from 1989 through 1993, on the basis of use of antiretroviral therapy and (after 1988) prophylaxis against Pneumocystis carinii pneumonia (PCP). Risk factors for HIV infection were homosexuality/bisexuality (30%), injection drug use (IDU; 22%), transfusion (5%), heterosexual contact (4%), and combinations of the above or unknown factors (38%); 95% of patients were males and 41% were state prison inmates in Texas. IDU was more common and homosexuality/ bisexuality was less common among inmates than among nonincarcerated patients. Mean survival time was 12 months in the first period studied and 23 months in the later period (P < .05). Cytomegalovirus infection was the most common type in both periods. The number of cases of PCP declined and the number of cases of bacterial infections increased significantly in the later period. Tuberculosis was significantly more common in inmates than in nonincarcerated patients. Tuberculosis and disseminated histoplasmosis (noted at autopsy) and deaths due to disseminated Mycobacterium avium complex and histoplasmosis were significantly more common among injection drug users than among homosexuals/bisexuals. Invasive candidiasis was more common in homosexuals/ bisexuals and in those who survived > 3 years. Antiretroviral therapy, prophylaxis for PCP, and risk factors for HIV infection appear to influence the mortality rate and prevalence of certain infections found at autopsy.

Effects of Clostridium perfringens recombinant and crude phospholipase C and theta-toxin on rabbit hemodynamic parameters

Clostridium perfringens exotoxins have been implicated as major virulence factors responsible for shock and organ failure in gas gangrene, yet the mechanism(s) by which they mediate cardiovascular dysfunction remain enigmatic. Recombinant (r) phospholipase C (PLC), r theta-toxin, culture supernatant (crude toxin), or 0.9% NaCl was infused intravenously into awake rabbits. Cardiac index (CI), mean arterial pressure (MAP), heart rate (HR), central venous pressure (CVP), arterial blood gases, and hematocrit were measured 1 h before and for 3 h after toxin infusion. Crude toxin and rPLC decreased CI, MAP, and HR and increased CVP; mortality was 87.5% and 83%, respectively. r theta-toxin did not decrease CI or MAP and mortality was 25%. Further, crude toxin and rPLC but not r theta-toxin inhibited cardiac contractility (dF/dt) in isolated rabbit atrial muscles. These results suggest that PLC-induced myocardial dysfunction contributes to shock in C. perfringens infection.