The majority of the 15.4 million human immunodeficiency virus (HIV)–infected women worldwide are of child-bearing age and need access to contraception. Hormonal methods of contraception are safe, acceptable, and effective in preventing unwanted pregnancies. Many published studies have examined the impact of hormonal contraception on HIV disease acquisition and transmissibility. Far fewer have investigated the relationship between hormonal contraception and HIV disease progression. This review examines available data on this relationship from clinical, animal, and immunological studies. Several clinical studies suggest an overall effect but are not definitive, and the mechanisms behind HIV disease progression are unclear. Animal and immunological data suggest that immunomodulation by hormonal contraceptive methods may affect the immune response to HIV infection. Additional work is needed in this area to elucidate the possible relationship between hormonal methods for birth control and progression to acquired immunodeficiency syndrome in HIV-infected women.
Valproic acid and intensified antiretroviral therapy may deplete resting CD4+ T-cell HIV infection. We tested the ability of valproic acid to deplete resting CD4+ T-cell infection in patients receiving standard antiretroviral therapy.
Resting CD4+ T-cell infection was measured in 11 stably aviremic volunteers twice prior to, and twice after Depakote ER 1000 mg was added to standard antiretroviral therapy. Resting CD4+ T-cell infection frequency was measured by outgrowth assay. Low-level viremia was quantitated by single copy plasma HIV RNA assay.
A decrease in resting CD4+ T-cell infection was observed in only four of the 11 patients. Levels of immune activation and HIV-specific T-cell response were low and stable. Valproic acid levels ranged from 26 to 96 μg/ml when measured near trough. Single copy assay was performed in nine patients. In three patients with depletion of resting CD4+ T-cell infection following valproic acid, single copy assay ranged from less than 1–5 copies/ml. Continuous low-level viremia was observed in three patients with stable resting CD4+ T-cell infection (24–87, 8–87, and 1–7 copies/ml respectively) in whom multiple samples were analyzed.
The prospective addition of valproic acid to stable antiretroviral therapy reduced the frequency of resting CD4+ T-cell infection in a minority of volunteers. In patients in whom resting CD4+ T-cell infection depletion was observed, viremia was rarely detectable by single copy assay.
antiretroviral therapy; HIV; latency; resting CD4+ T cells; valproic acid
Objectives and design
A vaccine capable of providing cross-clade, sterilizing protection has been the holy grail of HIV-1 prevention and control since the beginning of the pandemic. A major component of this effort has been the identification and characterization of broadly neutralizing antibodies (bNAbs). Recent advances in bNAb isolation, structure-based engineering, and vector-mediated gene transfer have led to increased interest in bypassing the immune system by expressing neutralizing antibodies directly in muscle. To assess the neutralization potency and coverage of a panel of second-generation bNAbs, we cloned and phenotypically characterized 227 primary HIV-1 envelopes from 23 mother-to-child transmission (MTCT) pairs.
Viral envelopes were tested for in-vitro neutralization sensitivity using a standard pseudotype assay system. A 50% inhibitory concentration (IC50) at least 10 μg/ml was used to define neutralization resistance.
The combination of antibodies PG16 and NIH45–46G54W had the broadest activity with the highest neutralization potency, achieving full coverage of 87% of transmission pairs (at a median sampling depth of 10 envelopes per pair) and 96% of recently infected infants in a very conservative analysis.
Our data strongly support the inclusion of NIH45–46G54W, or a more extensively modified variant, in future proof-of-principle immunoprophylaxis or gene therapy-based trials. Furthermore, until robust sequence-based resistance detection becomes available, it will be necessary to conduct deeper phenotypic screening of primary isolates in order to determine the prevalence of minor resistant variants to help in selecting the best reagents for clinical trials.
AIDS; antibodies; HIV; neutralization; paediatrics; prevention of mother-to-child transmission; vaccine
To compare the distribution of tenofovir in sheep vaginal lumen, tissue, and plasma following topical delivery of the antiretroviral drug from intravaginal rings, either as tenofovir or the disoproxil fumarate prodrug.
Comparative pharmacokinetic study in sheep.
Intravaginal rings formulated to achieve equivalent release rates of tenofovir and its disoproxil fumarate prodrug were evaluated for 28 days in sheep, with four animals in each group. Drug concentrations were measured by high-performance liquid chromatography–mass spectrometry.
Tenofovir levels in cervicovaginal lavage were indistinguishable (P > 0.30) in both groups, but tissue levels in animals receiving the prodrug were 86-fold higher than those receiving tenofovir, and approximately 50 times higher than the level shown to be protective of HIV infection in the CAPRISA 004 trial.
This is the first study to compare the pharmacokinetics of tenofovir and its disoproxil fumarate prodrug administered topically to the vaginal tract. These in-vivo data show that the prodrug leads to significantly higher drug tissue levels than tenofovir, a finding that may have important implications for the development of preexposure prophylaxis strategies based on topical delivery of antivirals to the female genital tract.
intravaginal ring; preexposure prophylaxis; sheep; tenofovir; tenofovir disoproxil fumarate; topical delivery
Experimental studies suggested that HMG-CoA reductase inhibitors (‘statins’) may have antilymphoma properties. We investigated whether statin use is associated with reduced risk of non-Hodgkin lymphoma (NHL) in HIV-positive persons.
A nested case–control study was conducted among HIV-positive members of Kaiser Permanente California, a large managed care organization.
Cases were incident HIV+NHL diagnosed from 1996 to 2008. Controls were HIV-positive members without NHL matched 5 : 1 to cases by age, sex, race, index year and known duration of HIV infection. Data were collected from Kaiser Permanente’s electronic medical records. Conditional logistic regression was used to examine the effect of statin use on HIV+NHL risk, adjusting for potential confounders (matching factors, prior clinical AIDS diagnosis, antiretroviral use, baseline CD4 cell count, and history of selected co-morbidity) and use of nonstatin lipid-lowering therapy (LLT).
A total of 259 cases and 1295 controls were included. Eight percent of the cases and 14% of the controls had a history of statin use. Statin use was associated with lower risk of HIV+NHL; hazard ratio and 95% confidence intervals for ever use, less than 12, and at least 12 months cumulative use was 0.55 (0.31–0.95), 0.64 (0.31–1.28), and 0.50 (0.23–1.10), respectively. P value for trend for duration of statin use was 0.08. No association between nonstatin LLT use and risk of NHL was observed.
Our results suggested an inverse association between statin use and risk of NHL in HIV-positive persons. Potential limitations include the likelihood of residual confounding by indication and limited study power for some statin use subgroups.
AIDS; HIV; HMG-CoA reductase; inhibitors; lymphoma; non-Hodgkin lymphoma; statins
The apolipoprotein E (APOE) ε4 allele enhances cerebral accumulation of β-amyloid (Aβ) and is a major risk factor for sporadic Alzheimer’s disease (AD). We hypothesized that HIV-associated neurocognitive disorders (HAND) would be associated with the APOE ε4 genotype and cerebral Aβ deposition.
Clinico-pathological study of HIV-infected adults from four prospective cohorts in the U.S. National NeuroAIDS Tissue Consortium.
We used multivariable logistic regressions to model outcomes (Aβ plaques [immunohistochemistry] and HAND [standard criteria]) on predictors (APOE ε4 [allelic discrimination assay], older age [≥ 50 years], Aβ plaques, and their two-way interactions) and co-morbid factors.
Isocortical Aβ deposits generally occurred as diffuse plaques and mild to moderate amyloid angiopathy. Isocortical phospho-Tau-immunoreactive neurofibrillary lesions were sparse. The APOE ε4 and older age were independently associated with the presence of Aβ plaques (adjusted odds ratio [OR] 10.16 and 5.77 [95% confidence interval (CI) 2.89–35.76 and 1.91–17.48], P=0.0003 and 0.0019, respectively, n=96). The probability of HAND was increased in the presence of Aβ plaques among APOE ε4 carriers (adjusted OR 30.00 [95% CI 1.41–638.63], P=0.029, n=15), but not in non-ε4 carriers (n=57).
The APOE ε4 and older age increased the likelihood of cerebral Aβ plaque deposition in HIV-infected adults. Generally Aβ plaques in HIV brains were immunohistologically different from those in symptomatic AD brains. Nonetheless, Aβ plaques were associated with HAND among APOE ε4 carriers. The detection of APOE ε4 genotype and cerebral Aβ deposition biomarkers may be useful in identifying living HAND subjects who could benefit from Aβ-targeted therapies.
Apolipoprotein E; β-amyloid; HIV dementia; neurofibrillary pathology; phospho-Tau
Measurement of adherence to antiretroviral therapy (ART) by patient self-report is common in resource-limited settings but widely believed to overstate actual adherence. The extent to which these measures overstate adherence has not been examined among a large patient population.
HIV-infected adult patients in Kenya who initiated ART within the past 3 months were followed for 6 months. Adherence was measured by participants’ self-reports of doses missed in the past 7 days during monthly clinic visits and by continuous Medication Event Monitoring System (MEMS) in participants’ pill bottles. Seven-day self-reported adherence was compared to 7-day MEMS adherence, 30-day MEMS adherence, and adherence more than 90% during each of the first 6 months.
Self-reported and MEMS adherence measures were linked for 669 participants. Mean 7-day self-reported adherence was 98.7% and mean 7-day MEMS adherence was 86.0%, a difference of 12.7% (P <0.01). The difference between the two adherence measures increased over time due to a decline in 7-day MEMS adherence. However, patients with lower MEMS adherence were in fact more likely to self-report missed doses and the difference between self-reported and MEMS adherence was similar for each number of self-reported missed doses. When analysis was limited to patients who reported rarely or never removing multiple doses at the same time, mean difference was 10.5% (P <0.01).
There is a sizable and significant difference between self-reported and MEMS adherence. However, a strong relationship between the measures suggests that self-reported adherence is informative for clinical monitoring and program evaluation.
adherence; adherence measurement; antiretroviral therapy; electronic monitoring
HIV-1 elite controllers (EC) spontaneously maintain suppressed levels of viremia, but exhibit significant immune activation. We investigated coronary atherosclerosis by coronary CT angiography (CTA) in: 1) EC, 2) non EC, chronically HIV-1 infected, ART-treated patients with undetectable viral load (“chronic HIV”), and 3) HIV-negative controls. Prevalence of atherosclerosis (78% vs. 42%, P<0.05) and markers of immune activation were increased in EC compared to HIV-negative controls. sCD163, a monocyte activation marker, was increased in EC compared to chronic HIV-1 (P<0.05) and compared to HIV-negative controls (P< 0.05). These data suggest a significant degree of coronary atherosclerosis and monocyte activation among EC.
Recent studies have raised concerns about a change in rates of pregnancy among HIV-negative women exposed to tenofovir. Here, our objective was to determine among HIV-positive women whether use of tenofovir at HAART initiation or thereafter is associated with subsequent changes in incidence of pregnancy.
Analysis of prospectively collected clinical data.
We used Cox proportional hazards models and logistic regression to estimate hazard ratios and odds-ratios for the association of baseline tenofovir use and time to first incident pregnancy. We used marginal structural Cox models to estimate hazard ratios for the association of current tenofovir use and time to first incident pregnancy.
We studied 7,275 women, of whom 1,199 were initiated on tenofovir-based HAART regimens, and who experienced a total of 894 pregnancies in 17,200 person-years of follow-up. Analyses showed slight reductions in hazards of pregnancy among women who used tenofovir, but without sufficient precision to draw strong conclusions. Sensitivity analyses confirmed main results.
Tenofovir may be associated with a lower hazard or rate of pregnancy in women receiving HAART. However, conclusions are limited by low precision, the observational nature of the data, and possible uncontrolled confounding by temporal trends in contraception use and other factors.
To determine magnitude and reasons of loss to programme and poor antiretroviral prophylaxis coverage in prevention of mother-to-child transmission (PMTCT) programmes in sub-Saharan Africa.
Systematic review and meta-analysis.
We searched PubMed and Embase databases for PMTCT studies in sub-Saharan Africa published between January 2002 and March 2012. Outcomes were the percentage of pregnant women (i) tested for HIV, (ii) initiating antiretroviral prophylaxis, (iii) having a CD4 cell count measured, and (iv) initiating antiretroviral combination therapy (cART) if eligible. In children outcomes were (v) early infant diagnosis for HIV, and (vi) cART initiation. We combined data using random-effects meta-analysis and identified predictors of uptake of interventions.
Forty-four studies from 15 countries including 75,172 HIV-infected pregnant women were analyzed. HIV-testing uptake at antenatal care services was 94% (95% confidence intervals [CI] 92-95%) for opt-out and 58% (95% CI 40-75%) for opt-in testing. Coverage with any antiretroviral prophylaxis was 70% (95% CI 64-76%) and 62% (95% CI 50-73%) of pregnant women eligible for cART received treatment. Sixty-four percent (95% CI 48-81%) of HIV exposed infants had early diagnosis performed and 55% (95% CI 36-74%) were tested between 12 and 18 months. Uptake of PMTCT interventions was improved if cART was provided at the antenatal clinic and if the male partner was involved.
In sub-Saharan Africa, uptake of PMTCT interventions and early infant diagnosis is unsatisfactory. An integrated family-centered approach seems to improve retention.
pre-ART; linkage to care; mortality; loss to follow-up; PMTCT; early infant diagnosis; prophylaxis
To evaluate the effectiveness of maternal combination antiretroviral prophylaxis for prevention of mother-to-child transmission of HIV (PMTCT) in a program setting
Prospective cohort study
Nine primary care clinics in rural Zambia
284 HIV-infected pregnant women at ≥28 weeks gestation initiating PMTCT services between April 2009 and January 2011 and their newborn infants
In four “intervention” sites, PMTCT comprised universal combination antiretroviral prophylaxis (i.e., irrespective of CD4 count) from pregnancy until the cessation of breastfeeding. In five “control” sites, women received antenatal zidovudine and peripartum nevirapine, the standard of care at the time. Prophylaxis during breastfeeding was not available in control sites.
Main outcome measure
Cumulative infant HIV infection and death at 12 months postpartum
At 12 month postpartum, 1 of 104 (1.0%) infants born to mothers at the intervention sites were HIV-infected, compared to 14 of 116 (12.1%) receiving care in the control sites (relative risk [RR]: 12.6, 95%CI: 2.2-73.1; P=0.005). When we considered the composite outcome of HIV infection or death, similar trends were observed in the overall study population (RR: 3.4, 95%CI: 1.6-7.6; P=0.002) and in a sub-analysis of women with CD4 >350 cells/μL (RR: 3.2; 95%CI: 1.1-9.6; P=0.04).
When compared to PMTCT services based on antenatal zidovudine and peripartum nevirapine, the provision of maternal combination prophylaxis imparted measurable health benefits to HIV-exposed infants. Implementation research is needed to further tailor and optimize these strategies for similar field settings.
HIV; prevention of mother to child transmission; antiretroviral therapy; breastfeeding; Zambia
Our aim was to project the outcomes of using either efavirenz or nevirapine as part of initial antiretroviral therapy (ART) in women of childbearing age in Côte d’Ivoire.
We used an HIV computer simulation model to project both the mother’s survival and the birth defects at 10 years for a cohort of women who started ART with either efavirenz or nevirapine. The primary outcome was the ratio at 10 years of the difference in the number of women alive to the difference in the cumulative number of birth defects in women who started ART with efavirenz compared to nevirapine. In the base case analysis, the birth defect rate was 2.9% on efavirenz and 2.7% on nevirapine. In sensitivity analyses we varied all inputs across confidence intervals reported in the literature.
In the base case analysis, for a cohort of 100,000 women, the additional number of women alive initiating ART with efavirenz at 10 years was 15 times the additional number of birth defects (women alive: nevirapine 67,969, efavirenz 68,880, difference = 911; birth defects: nevirapine 1,128, efavirenz 1,187, difference = 59). In sensitivity analysis, the teratogenicity rate with efavirenz had to be 6.3%, or 2.3 times higher than the rate with nevirapine, for the excess number of birth defects to outweigh the additional number of women alive at 10 years.
In Côte d’Ivoire, initiating ART with efavirenz instead of nevirapine is likely to substantially increase the number of women alive at 10 years with a smaller potential number of birth defects.
efavirenz; women; sub-Saharan Africa; teratogenicity; survival; pregnancy; antiretroviral therapy
papillomavirus infections; HIV; meta-analysis; human papillomavirus; risk factors
The prevalence of HPV is higher among HIV+ women, but the prevalence of HPV prior to HIV acquisition has not been carefully evaluated.
This study evaluated whether HPV infection is independently associated with heterosexual HIV acquisition in a cohort of Zimbabwean women.
Case-control study nested within a large multi-center cohort study (HC-HIV).
Cases consisted of Zimbabwean women with incident HIV infection observed during follow-up (n=145). HIV-uninfected controls were selected and matched to cases (n=446). The prevalence of cervical HPV infections was compared at the visit prior to HIV infection in the cases and at the same follow-up visit in the matched controls.
The odds of acquiring HIV were 2.4 times higher in women with prior cervical HPV infection after adjustment for behavioral and biologic risk factors. There was no statistically significant difference in the risk of HIV acquisition between women infected with high versus low risk HPV types. Loss of detection of at least one HPV DNA type was significantly associated with HIV acquisition (OR =5.4 [95%CI, 2.9–9.9] (p<.0001).
Cervical HPV infection is associated with HIV acquisition among women residing in a region with a high prevalence of both infections. Further studies are required to evaluate whether the observed association is causal.
HPV; heterosexual HIV transmission; HIV prevention; cervical HPV; STI
Mortality rates are high in antiretroviral therapy (ART) programmes in sub-Saharan Africa, especially during the first few months of treatment. Tuberculosis (TB) has been identified as a major underlying cause. Under routine programme conditions, between 5% and 40% of adult patients enrolling in ART services have a baseline diagnosis of TB. There is also a high TB incidence during the first few months of ART (much of which is prevalent disease missed by baseline screening) and long-term rates remain several-fold higher than background. We identify three groups of patients entering ART programmes for which different interventions are required to reduce TB-related deaths. First, diagnostic screening is needed in patients who have undiagnosed active TB so that timely anti-tuberculosis treatment can be started. This may be greatly facilitated by new diagnostic assays such as the Xpert MTB/RIF assay. Second, patients with a diagnosis of active TB need optimised case management, which includes early initiation of ART (with timing now defined by randomised controlled trials), trimethoprim-sulphamethoxazole prophylaxis and treatment of co-morbidity. Third, all remaining patients who are TB-free at enrolment have high ongoing risk of developing TB and require optimised immune recovery (with ART ideally started early in the course of HIV infection), isoniazid preventive therapy and infection control to reduce infection risk. Further specific measures are needed to address multi-drug resistant TB (MDR-TB). Finally, scale-up of all these interventions requires nationally and locally tailored models of care that are patient-centred and provide integrated health care delivery for TB, HIV and other co-morbidities.
HIV; tuberculosis; antiretroviral; death; mortality; Africa
Regulatory T cells (Tregs) are potent immune modulators, but their precise role in HIV pathogenesis remains incompletely understood. Most studies to date have focused on frequencies or phenotypes of “bulk” Treg populations. However, although antigen-specific Tregs have been reported in other diseases, HIV-1-epitope specific Tregs have not been described to date. We here report the first identification of functional HIV-1-Gag-specific regulatory T cells using human leukocyte antigen class II tetramer staining in HIV-1-infected individuals.
HIV; tuberculosis; screening; diagnosis; mortality; antiretroviral
Two-thirds of the world's HIV-infected people live in sub-Saharan Africa and more than 1.5 million of them die annually. As access to antiretroviral treatment (ART) has expanded within the region, early pessimism concerning the delivery of ART using a large-scale public health approach has, at least in the short term, proved to be broadly unfounded. Immunological and virological responses to ART are similar to responses in patients treated in high-income countries. Despite this, however, early mortality rates in sub-Saharan Africa are very high; between 8% and 26% of patients die in the first year of ART, with most deaths occurring in the first few months. Patients typically access ART with advanced symptomatic disease, and mortality is strongly associated with baseline CD4 cell count <50 cells/μL and WHO stage 4 disease (AIDS). Although data are limited, leading causes of death appear to be tuberculosis, acute sepsis, cryptococcal meningitis, malignancy and wasting syndrome. Mortality rates are likely to depend not only on the care delivered by ART programmes, but more fundamentally on how advanced disease is at programme enrolment and the quality of preceding health-care. In addition to improving delivery of ART and providing this free of charge to the patient, strategies to reduce mortality must include earlier diagnosis of HIV infection, strengthening of longitudinal HIV care and timely initiation of ART. Health systems delays in ART initiation must be minimised, especially in patients who present with advanced immunodeficiency.
HIV; AIDS; antiretroviral treatment; HAART; ART; mortality; death; Africa
To analyse mortality, loss to follow-up (LTFU) and retention on antiretroviral treatment (ART) in the first year of ART across all age-groups in the Malawi national ART programme.
Cohort study including all patients who started ART in Malawi’s public sector clinics between 2004 and 2007.
ART registers were photographed, information entered into a database and merged with data from clinics with electronic records. Rates per 100 patient-years and cumulative incidence of retention were calculated. Subhazard ratios (sHR) of outcomes adjusted for patient and clinic level characteristics were calculated in multivariate analysis, applying competing risk models.
A total of 117,945 patients contributed 85,246 person-years: 1.0% were infants <2 years, 7.4 % children 2–14, 7.5% young people 15–24, and 84.2% adults 25 years and above. Sixty percent of patients were female: women outnumbered men from age 14 to 35 years. Mortality and LTFU were higher in men from age 20 years. Infants and young people had the highest rates per 100 person-years for mortality (23.0 and 19.4) and LTFU (24.7 and 19.3), and the highest adjusted relative risks compared to age group 25–34 years: sHRs were 1.37 (95%CI 1.17–1.60) and 1.17 (95%CI 1.10–1.25) for death and 1.37 (95%CI 1.18–1.59) and 1.27 (95%CI 1.19–1.35) for LTFU, respectively.
In this country-wide study patients aged 0–1 and 15–24 years had the highest risk of death and LTFU, and from age 20 and older men were at higher risk than women. Interventions to improve outcomes in these patient groups are required.
Antiretroviral therapy; Malawi; mortality; loss to follow-up; retention on ART
A family of histone deacetylases (HDACs) mediates chromatin remodeling, and repression of gene expression. Deacetylation of histones within the HIV-1 long terminal repeat (LTR) by HDACs plays a key role in the maintenance of latency, whereas acetylation of histones about the LTR is linked to proviral expression and escape of HIV from latency. Global HDAC inhibition may adversely affect host gene expression, leading to cellular toxicities. Potent inhibitors selective for HDACs that maintain LTR repression could be ideal antilatency therapeutics.
We investigated the ability of selective HDAC inhibitors to de-repress the HIV-1 LTR in both a cell line model of latency and in resting CD4+ T cells isolated from patients who were aviremic on antiretroviral therapy (ART).
We found that inhibition of class I HDACs increased acetylation of histones at the LTR, but that LTR chromatin was unaffected by class II HDAC inhibitors. In a latently infected cell line, inhibitors selective for class I HDACs were more efficient activators of the LTR than inhibitors that target class II HDACs. Class I HDAC inhibitors were strikingly efficient inducers of virus outgrowth from resting CD4+ T cells of aviremic patients, whereas HIV was rarely recovered from patient’s cells exposed to class II HDAC inhibitors.
Further development of selective HDAC inhibitors as part of a clinical strategy to target persistent HIV infection is warranted.
histone deacetylase; HIV; latency; long terminal repeat; resting CD4+ T cells
Both protective T cell genotypes and NK cell genotypes have been associated with delayed progression to AIDS and shown to be co-inherited in HIV-1 infected subjects who limit viral replication in absence of antiretroviral therapy (“controllers”). However, a comparative analysis of the genotype and function of the innate and adaptive immune compartments in HIV-1 infected controller subjects has been understudied to date.
Here, we simultaneously tested NK and T cell function in controllers to investigate the mechanism(s) that might account for host-immune control over viral replication.
We measured CD8 T cell responses against HIV-1 utilizing overlapping 15-mer peptides spanning the HIV-1 Consensus Clade B Gag protein and tested NK cell degranulation and cytokine secretion against tumor target cells following IFN-alpha stimulation.
Among a cohort of 37 controllers, the presence of protective MHC-Class I HLA alleles (such as HLA-B*57) was not correlated with HIV-specific CD8 responses. In contrast, the inheritance of a protective KIR3DL1*h/*y receptor genotype along with the corresponding HLA-Bw4*80I ligand was associated with significantly heightened target cell-induced NK degranulation and cytokine secretion following IFN-alpha stimulation (p=0.0201, n=13). Interestingly, we observed a significant inverse association between the IFN-alpha stimulated NK response to K562 cells and the HIV-specific CD8 T cell response to Gag among elite controllers. (rho=−0.8321, p=0.0010, n=12).
Together, these results suggest that heightened NK responses can be evidenced independently of HIV-specific T cell responses in HIV-1 infected elite controllers.
HIV-1; AIDS; T Cells; NK Cells; HLA; KIR; Elite Controllers
To investigate the susceptibilities to and consequences of HIV-1 dual infection (DI).
We compared clinical, virologic, and immunologic factors between participants who were dually infected with HIV-1 subtype B, and monoinfected (MI) controls who were matched by ongoing HIV risk factor.
The viral load and CD4 progressions of dually and singly infected participant groups were compared with linear mixed-effects models, and individual dynamics before and after superinfection were assessed with a structural change test (Chow test). Recombination breakpoint analysis (GARD), HLA frequency analysis, and cytotoxic T-lymphocyte (CTL) epitope mapping were also performed (HIV LANL Database).
The viral loads of DI participants increased more over 3 years of follow-up than the viral loads of MI controls, while CD4 progressions of the two groups did not differ. Viral escape from CTL responses following superinfection was observed in two participants whose superinfecting strain completely replaced the initial strain. This pattern was not seen among participants whose superinfecting virus persisted in a recombinant form with the initial virus or was only detected transiently. Several HLA types were overrepresented in DI participants as compared to MI controls.
These results identify potential factors for DI susceptibility and further define its clinical consequences.
HIV-1 dual infection; viral load; CD4 count; HLA; CTL