Association between paired plasma and cervicovaginal lavage fluid HIV-1 RNA levels during 36 months

Detection of cytokines in cervicovaginal lavage in HIV-infected women and its association with high-risk human papillomavirus

Background

Women living with HIV/AIDS (WLHA) have an increased prevalence of high-risk HPV infection (HR-HPV) and cervical intraepithelial neoplasia (CIN) and a greater risk of cervical cancer despite access to a new generation of antiretroviral therapy. The aim of this study is to evaluate the concentrations of different cytokines involved in the local immune response in WLHA, which is fundamental for understanding the pathogenesis of HPV-related cancer in this population.

Methods

IL-1β, IL-2, IL-4, IL-6, IL-10, IFN-γ, TNF-α, IP-10, GM-CSF, and MIP-1α were investigated in the cervicovaginal lavage (CVL) of 106 WLHA attending at Hospital Universitario Professor Edgard Santos in Salvador, Bahia, Brazil, during the period December 2019 to April 2023 by Luminex®. All participants were also tested for Chlamydia trachomatis and Neisseria gonorrhoeae and underwent colposcopy, Pap smear, and Nugent score. HIV plasma viral load (VL) and CD4 cell count were performed for all WLHA.

Results

In this study, 22.6% (24/106) of WLHA were infected with HR-HPV. A higher proportion of patients with HR-HPV (66.7%) had detectable levels of IL-10 than those negative ones (40.2%, p = 0.02). More premenopausal women had either IL-6 (51.4%) or IP-10 (58.3%) than those in menopausal status (26.5% for IL-6 and 32.4% for IP-10, p = 0.013 and p = 0.011, respectively). Vaginosis was negatively associated with detection of IP-10 (24.2% vs. 61.4%, p < 0.001) and INF-γ (39.4% vs. 68.6%, p = 0.005). A positive association was detected for IL-1β (66.7 vs. 37.1%, p = 0.005) and IL-10 (63.6% vs. 37.1%, p = 0.01). VL and CD4 were not associated with the studied cytokines.

Conclusion

We demonstrated a positive association between IL-10 and HPV infection in CVL, suggesting the predominance of the Th2 response in HIV/HPV co-infected patients. However, further studies with longer follow-up will be needed to evaluate the association of IL-10 with HPV infection, CIN, and cervical cancer in WLHA.

The multifaceted nature of HIV tissue reservoirs

PURPOSE OF REVIEW

To underline the complexity and the heterogeneity of the HIV reservoir.

RECENT FINDINGS

While lymphoid tissues (spleen, lymph nodes, gut-associated lymphoid tissue) harbor specific subsets of specialized CD4 +  T cells enriched in HIV-infected cells, non-CD4 +  T cell reservoirs such as tissue-resident macrophages and dendritic cells have also been implicated to contribute to viral persistence. Moreover, studies have applied highly sensitive tools to detect transcriptional activity within HIV-infected cells during prolonged ART and revealed a broader spectrum of transcriptional activity for proviruses than previously thought. Finally, while a combination of factors might be involved in the regulation of HIV persistence within different tissues and remains to be fully elucidated, recent results from autopsy samples of HIV-infected ART suppressed individuals indicate extensive clonality of HIV reservoirs in multiple tissues and suggest that the recirculation of HIV-infected cells and their local expansions in tissues may also contribute to the complexity of the HIV reservoirs in humans.

SUMMARY

HIV persistence in blood and multiple tissues despite long-standing and potent therapy is one of the major barriers to a cure. Given that the HIV reservoir is established early and is highly complex based on its composition, viral diversity, tissue distribution, transcriptional activity, replication competence, migration dynamics and proliferative potential across the human body and possible compartmentalization in specific tissues, combinatorial therapeutic approaches are needed that may synergize to target multiple viral reservoirs to achieve a cure for HIV infection.

Human Immunodeficiency Virus Type 1 RNA Genital Tract Shedding After Cryotherapy for Cervical Intraepithelial Neoplasia in Western Kenya

This prospective study of 39 women living with human immunodeficiency virus (HIV) on antiretroviral therapy in Western Kenya aimed to quantify genital tract HIV-1 RNA (GT-HIV RNA) shedding before and after cryotherapy for cervical intraepithelial neoplasia. Most GT-HIV RNA shedding was detected precryotherapy, suggesting that cryotherapy was not the primary cause of shedding.

Crucial Role of Central Nervous System as a Viral Anatomical Compartment for HIV-1 Infection

The chronic infection established by the human immunodeficiency virus 1 (HIV-1) produces serious CD4+ T cell immunodeficiency despite the decrease in HIV-1 ribonucleic acid (RNA) levels and the raised life expectancy of people living with HIV-1 (PLWH) through treatment with combined antiretroviral therapies (cART). HIV-1 enters the central nervous system (CNS), where perivascular macrophages and microglia are infected. Serious neurodegenerative symptoms related to HIV-associated neurocognitive disorders (HAND) are produced by infection of the CNS. Despite advances in the treatment of this infection, HAND significantly contribute to morbidity and mortality globally. The pathogenesis and the role of inflammation in HAND are still incompletely understood. Principally, growing evidence shows that the CNS is an anatomical reservoir for viral infection and replication, and that its compartmentalization can trigger the evolution of neurological damage and thus make virus eradication more difficult. In this review, important concepts for understanding HAND and neuropathogenesis as well as the viral proteins involved in the CNS as an anatomical reservoir for HIV infection are discussed. In addition, an overview of the recent advancements towards therapeutic strategies for the treatment of HAND is presented. Further neurological research is needed to address neurodegenerative difficulties in people living with HIV, specifically regarding CNS viral reservoirs and their effects on eradication.

Genital Shedding of Human Immunodeficiency Virus Type-1 (HIV) When Antiretroviral Therapy Suppresses HIV Replication in the Plasma

BACKGROUND

During antiretroviral treatment (ART) with plasma HIV RNA below the limit of quantification, HIV RNA can be detected in genital or rectal secretions, termed discordant shedding (DS). We hypothesized that proliferating cells produce virions without HIV replication.

METHODS

ART-naive Peruvians initiating ART were observed for DS over 2 years. HIV env and pol genomes were amplified from DS. Antiretrovirals and cytokines/chemokines concentrations were compared at DS and control time points.

RESULTS

Eighty-two participants had ART suppression. DS was detected in 24/82 (29%) participants: 13/253 (5%) cervicovaginal lavages, 20/322 (6%) seminal plasmas, and 6/85 (7%) rectal secretions. HIV RNA in DS specimens was near the limit of quantification and not reproducible. HIV DNA was detected in 6/13 (46%) DS cervicovaginal lavages at low levels. Following DNase treatment, 5/39 DS specimens yielded HIV sequences, all without increased genetic distances. Women with and without DS had similar plasma antiretroviral levels and DS in 1 woman was associated with inflammation.

CONCLUSIONS

HIV RNA and DNA sequences and therapeutic antiretroviral plasma levels did not support HIV replication as the cause of DS from the genital tract. Rather, our findings infer that HIV RNA is shed due to proliferation of infected cells with virion production.

High discordance in blood and genital tract HIV-1 drug resistance in Indian women failing first-line therapy

Objectives

Examine HIV-1 plasma viral load (PVL) and genital tract (GT) viral load (GVL) and drug resistance in India.

Methods

At the YRG Centre for AIDS Research and Education, Chennai, we tested: PVL in women on first-line ART for ≥6 months; GVL when PVL >2000 copies/mL; and plasma, genital and proviral reverse transcriptase drug resistance when GVL >2000 copies/mL. Wilcoxon rank-sum and Fisher's exact tests were used to identify failure and resistance associations. Pearson correlations were calculated to evaluate PVL-GVL associations. Inter-compartmental resistance discordance was evaluated using generalized estimating equations.

Results

Of 200 women, 37% had detectable (>400 copies/mL) PVL and 31% had PVL >1000 copies/mL. Of women with detectable PVL, 74% had PVL >2000 copies/mL, of which 74% had detectable GVL. Higher PVL was associated with higher GVL. Paired plasma and genital sequences were available for 21 women; mean age of 34 years, median ART duration of 33 months, median CD4 count of 217 cells/mm3, median PVL of 5.4 log10 copies/mL and median GVL of 4.6 log10 copies/mL. Drug resistance was detected in 81%-91% of samples and 67%-76% of samples had dual-class resistance. Complete three-compartment concordance was seen in only 10% of women. GT-proviral discordance was significantly larger than plasma-proviral discordance. GT or proviral mutations discordant from plasma led to clinically relevant resistance in 24% and 30%, respectively.

Conclusions

We identified high resistance and high inter-compartmental resistance discordance in Indian women, which might lead to unrecognized resistance transmission and re-emergence compromising treatment outcomes, particularly relevant to countries like India, where sexual HIV transmission is predominant.

Rilpivirine Plasma and Cervicovaginal Concentrations in Women During Pregnancy and Postpartum

BACKGROUND

Concentrations of antiretrovirals in the genital tract play a key role in preexposure prophylaxis. This study aims to describe rilpivirine (Edurant) concentrations in the genital tract in pregnant and postpartum women.

METHODS

International Maternal Pediatric Adolescent AIDS Clinical Trials Protocol P1026s is an ongoing, prospective study of antiretroviral pharmacokinetics in HIV-infected pregnant women that include a cohort receiving rilpivirine combination regimen. Intensive pharmacokinetics evaluations were performed at steady state during the second and third trimester, and postpartum. Plasma and directly aspirated cervicovaginal fluid (CVF) samples were collected at 4 time points around an observed dose and measured using high-performance liquid chromatography with ultraviolet detection, [plasma; lower limit of quantification (LLQ) = 10 ng/mL] or liquid chromatography-tandem mass spectrometry (CVF; LLQ = 1 ng/mL).

RESULTS

A total of 24 women were included in the analysis. For all time points combined, median (interquartile range) rilpivirine concentrations were 70 ng/mL (23-121) in CVF and 92 ng/mL (49-147) in plasma. The CVF to plasma AUC(0-4) ratios were significantly higher in the second (0.90, 90% CI: 0.61 to 1.46) and third trimesters of pregnancy compared with postpartum (0.40, 90% CI: 0.19 to 0.87). Three of 189 (1.6%) plasma samples in 2 women were below the LLQ and the corresponding CVF concentrations. Seventeen additional CVF concentrations (10.6%) were below LLQ in 13 participants. No major safety concerns were noted.

CONCLUSIONS

Rilpivirine concentrations were higher in the CVF during pregnancy compared with postpartum. CVF Rilpivirine is likely to achieve inhibitory concentrations effective for preventing peripartum HIV transmission.

Genital reservoir: a barrier to functional cure?

PURPOSE OF REVIEW

HIV functional cure requires the elimination or a major reduction of HIV reservoir pool including male and female genital HIV reservoirs. A comprehensive understanding of HIV dynamics in these compartments is mandatory.

RECENT FINDINGS

Data from chronically HIV-infected therapy-naïve individuals or fully suppressed on combined antiretroviral therapy (cART) or undergoing ART interruptions are now available. Using paired blood/genital samples, HIV-RNA/DNA quantification and sequencing provide new insights on HIV dynamics in genital reservoirs.

SUMMARY

In the absence of cART, HIV shedding in semen and cervicovaginal secretions is frequent, resulting most likely from passive transfer of HIV strains that originates from bloodborne virions or infected blood cells. Partial and intermittent HIV compartmentalization in the male and female genital tracts can occur not only in chronically infected ART-naïve individuals but also when cART is used to prevent active blood replication. This transient autonomous HIV replication in the genital reservoir in a few individuals originates from recent transfer of virions or infected blood cells. cART interruption studies showed that blood and genital quasispecies are closely related, in agreement with a passive transfer. Altogether these data suggest that HIV genital reservoirs seem not to be a significant barrier to achieve HIV cure.

A randomized clinical trial on the effects of progestin contraception in the genital tract of HIV-infected and uninfected women in Lilongwe, Malawi: Addressing evolving research priorities

Hormonal contraception is central in the prevention of unintended pregnancy; however there are concerns that certain methods may increase the risk of HIV acquisition and transmission. Hormonal contraceptives may modify the genital mucosa in several ways, however the mechanisms are incompletely understood. Few studies have examined genital HIV shedding prospectively before and after initiation of hormonal contraception. The effects of hormonal contraception on genital HIV shedding in the setting of antiretroviral therapy (ART) are also unknown. We designed a pilot clinical trial in which HIV-infected and uninfected women were randomized to either depot medroxyprogesterone acetate (DMPA) injectable or levonorgestrel (LNG) implant in Lilongwe, Malawi. The objectives were to: 1) assess the effect and compare the impact of type of progestin contraception (injectable versus implant) on HIV genital shedding among HIV-infected women, 2) assess the effect and compare the impact of type of progestin contraception on inflammatory/immune markers in the genital tract of both HIV-infected and uninfected women, and 3) assess the interaction of progestin contraception and ART by examining contraceptive efficacy and ART efficacy. An additional study aim was to determine the feasibility and need for a larger study of determinants of HIV transmissibility and acquisition. As injectable contraception is widely used in many parts of the world with high HIV prevalence, this study will provide important information in determining the need for and feasibility of a larger study to address these questions that can impact the lives of millions of women living with or at risk for HIV.

Compartmentalization, Viral Evolution, and Viral Latency of HIV in the CNS

Human immunodeficiency virus type 1 (HIV-1) infection occurs throughout the body and can have dramatic physical effects, such as neurocognitive impairment in the central nervous system (CNS). Furthermore, examining the virus that resides in the CNS is challenging due to its location and can only be done using samples collected either at autopsy, indirectly form the cerebral spinal fluid (CSF), or through the use of animal models. The unique milieu of the CNS fosters viral compartmentalization as well as evolution of viral sequences, allowing for new cell types, such as macrophages and microglia, to be infected. Treatment must also cross the blood-brain barrier adding additional obstacles in eliminating viral populations in the CNS. These long-lived infected cell types and treatment barriers may affect functional cure strategies in people on highly active antiretroviral therapy (HAART).

Evaluation of Performance Characteristics of the Aptima HIV-1 Quant Dx Assay for Detection and Quantitation of Human Immunodeficiency Virus Type 1 in Plasma and Cervicovaginal Lavage Samples

Quantification of HIV-1 RNA has become the standard of care in the clinical management of HIV-1-infected individuals. The objective of this study was to evaluate performance characteristics and relative workflow of the Aptima HIV-1 Quant Dx assay in comparison with the Abbott RealTime HIV-1 assay using plasma and cervicovaginal lavage (CVL) specimens. Assay performance was evaluated by using an AcroMetrix HIV-1 panel, AcroMetrix positive controls, Qnostics and SeraCare HIV-1 evaluation panels, 208 clinical plasma samples, and 205 matched CVL specimens on the Panther and m2000 platforms. The Aptima assay demonstrated good linearity over the quantification range tested (2 to 5 log10copies/ml), and there was strong linear correlation between the assays (R(2)= 0.99), with a comparable coefficient of variance of <5.5%. For the plasma samples, Deming regression analyses and Bland-Altman plots showed excellent agreement between the assays, with an interassay concordance of 91.35% (kappa = 0.75; 95% confidence interval [CI], 0.65 to 0.85), and on average, the viral loads determined by the Aptima assay were 0.21 log10copies/ml higher than those determined by the RealTime assay. The assays differed in their sensitivity for quantifying HIV-1 RNA loads in CVL samples, with the Aptima and RealTime assays detecting 30% and 20%, respectively. Aptima had fewer invalid results, and on average, the viral loads in CVL samples quantified by the Aptima assay were 0.072 log10copies/ml higher than those of the RealTime assay. Our results demonstrate that the Aptima assay is sensitive and accurate in quantifying viral loads in both plasma and CVL specimens and that the fully automated Panther system has all the necessary features suitable for clinical laboratories demanding high-throughput sample processing.

Relationship Between Genital Drug Concentrations and Cervical Cellular Immune Activation and Reconstitution in HIV-1-Infected Women on a Raltegravir Versus a Boosted Atazanavir Regimen

Determinants of HIV-infected women's genital tract mucosal immune health are not well understood. Because raltegravir (RAL) achieves relatively higher genital tract concentrations than ritonavir-boosted atazanavir (ATV), we examined whether an RAL-based regimen is associated with improved cervical immune reconstitution and less activation in HIV(+) women compared to an ATV-based regimen. Peripheral blood, cervical brushings, cervical-vaginal lavage (CVL), and cervical biopsies were collected from HIV(+) women on tenofovir disoproxil fumarate and emtricitabine (TDF/FTC) and either RAL (n=14) or ATV (n=19) with CD4(+) T cells>300 cells/mm(3) and HIV RNA<48 copies/ml. HLA-DR(+)CD38(+) T cells were measured in blood and cervical cells using flow cytometry, CD4(+) and CD8(+) T cells were quantified in cervical biopsies by immunofluorescent analysis, and HIV RNA (VL), ATV, and RAL concentrations were measured in CVL. In a linear regression model of log(CVL concentration) versus both log(plasma concentration) and treatment group, the RAL CVL level was 519% (95% CI: 133, 1,525%) higher than for ATV (p<0.001). Genital tract VL was undetectable in 90% of subjects and did not differ by regimen. There were no significant differences between groups in terms of cervical %HLA-DR(+)CD38(+)CD4(+) or CD8(+) T cells, CD4(+) or CD8(+) T cells/mm(2), or CD4:CD8 ratio. After adjusting for treatment time and group, the CVL:plasma drug ratio was not associated with the cervical CD4:CD8 ratio or immune activation (p>0.6). Despite significantly higher genital tract penetration of RAL compared to ATV, there were no significant differences in cervical immune activation or reconstitution between women on these regimens, suggesting both drug regimens achieve adequate genital tract levels to suppress virus replication.

Twelve-Month Antiretroviral Therapy Suppresses Plasma and Genital Viral Loads but Fails to Alter Genital Levels of Cytokines, in a Cohort of HIV-Infected Rwandan Women

Background

Genital viral load (GVL) is the main determinant of sexual transmission of human immune-deficiency virus (HIV). The effect of antiretroviral therapy (ART) on local cervico-vaginal immunological factors associated with GVL is poorly described. We aimed to identify the risk factors of detectable GVL, and the impact of ART on HIV genital shedding and its correlates in a cohort of HIV-infected women, attending HIV care in Kigali, Rwanda.

Materials and Methods

All participants were evaluated for GVL, plasma viral load (PVL), CD4 count, various sexually-transmitted infections (STIs) at baseline and at month 12. Genital concentration of 19 cytokines and mRNA expression of APOBEC3G and BST2, two host HIV restriction factors, were evaluated at baseline in all participants. Cytokine levels were re-assessed at month 12 only in participants eligible for ART at baseline. Risk factors of GVL ≥40copies/mL at baseline and month 12 were assessed using logistic regression. Effect of 12-month ART on various local and systemic immunological parameters was examined using a paired t-test and McNemar as appropriate.

Results

96 of the 247 women enrolled in the study were eligible for ART. After 12 months of ART, PVL and GVL decreased to undetectable level in respectively 74 and 88% of treated participants. ART did not affect cytokine levels. HIV genital shedding occurred only when PVL was detectable. At baseline, GVL was independently associated with IL-1β after controlling for PVL, age and N. gonorrhea infection (95% CI 1.32-2.15) and at month 12 with MIP-1β (95% CI 0.96-21.32) after controlling for baseline GVL, PVL and month 12 IL-8.

Conclusion

Suppressive ART does not necessarily reduce genital level of immune activation. Minimizing all conditions favoring genital inflammation, including active detection and treatment of STIs, might reduce the risk of HIV transmission as supplement to the provision of potent ART.

HIV-1 genital shedding is suppressed in the setting of high genital antiretroviral drug concentrations throughout the menstrual cycle

BACKGROUND

It is not known if fluctuations in genital tract antiretroviral drug concentrations correlate with genital virus shedding in human immunodeficiency virus (HIV)-infected women on antiretroviral therapy (ART).

METHODS

Among 20 HIV-infected women on ART (tenofovir [TFV], emtricitabine [FTC], and ritonavir-boosted atazanavir [ATV]) with suppressed plasma virus loads, blood and cervicovaginal samples collected twice weekly for 3 weeks were tested for antiretroviral concentrations, HIV-1 RNA, and proviral DNA.

RESULTS

Cervicovaginal:plasma antiretroviral concentration ratios were highest for FTC (11.9, 95% confidence interval [CI], 8.66-16.3), then TFV (3.52, 95% CI, 2.27-5.48), and ATV (2.39, 95% CI, 1.69-3.38). Within- and between-person variations in plasma and genital antiretroviral concentrations were observed. Low amounts of genital HIV-1 RNA (<50 copies/mL) were detected in 45% of women at 16% of visits. Genital HIV-1 DNA was detected in 70% of women at 35% of visits. Genital virus detection was associated with higher concentrations of mucosal leukocytes but not with genital antiretroviral concentrations, menstrual cycle phase, bacterial vaginosis, genital bleeding, or plasma virus detection.

CONCLUSIONS

Standard doses of ART achieved higher genital than plasma concentrations across the menstrual cycle. Therapeutic ART suppresses genital virus shedding throughout the menstrual cycle, even in the presence of factors reported to increase virus shedding.

HIV-1 RNA levels and antiretroviral drug resistance in blood and non-blood compartments from HIV-1-infected men and women enrolled in AIDS clinical trials group study A5077

BACKGROUND

Detectable HIV-1 in body compartments can lead to transmission and antiretroviral resistance. Although sex differences in viral shedding have been demonstrated, mechanisms and magnitude are unclear. We compared RNA levels in blood, genital-secretions and saliva; and drug resistance in plasma and genital-secretions of men and women starting/changing antiretroviral therapy (ART) in the AIDS Clinical Trials Group (ACTG) 5077 study.

METHODS

Blood, saliva and genital-secretions (compartment fluids) were collected from HIV-infected adults (≥ 13 years) at 14 United-States sites, who were initiating or changing ART with plasma viral load (VL) ≥ 2,000 copies/mL. VL testing was performed on all compartment fluids and HIV resistance genotyping on plasma and genital-secretions. Spearman rank correlations were used to evaluate concordance and Fisher's and McNemar's exact tests to compare VL between sexes and among compartments.

RESULTS

Samples were available for 143 subjects; 36% treated (23 men, 29 women) and 64% 'untreated' (40 men, 51 women). RNA detection was significantly more frequent in plasma (100%) than genital-secretions (57%) and saliva (64%) (P<0.001). A higher proportion of men had genital shedding versus women (78% versus 41%), and RNA detection was more frequent in saliva versus genital-secretions in women when adjusted for censoring at the limit of assay detection. Inter-compartment fluid VL concordance was low in both sexes. In 22 (13 men, 9 women) paired plasma-genital-secretion genotypes from treated subjects, most had detectable resistance in both plasma (77%) and genital-secretions (68%). Resistance discordance was observed between compartments in 14% of subjects.

CONCLUSIONS

HIV shedding and drug resistance detection prior to initiation/change of ART in ACTG 5077 subjects differed among tissues and between sexes, making the gold standard blood-plasma compartment assessment not fully representative of HIV at other tissue sites. Mechanisms of potential sex-dependent tissue compartmentalization should be further characterized to aid in optimizing treatment and prevention of HIV transmission.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00007488.

Cervicovaginal HIV-1 shedding in women taking antiretroviral therapy in Burkina Faso: a longitudinal study

BACKGROUND

Antiretroviral therapy (ART) reduces transmission of HIV-1. However, genital HIV-1 can be detected in patients on ART. We analyzed factors associated with genital HIV-1 shedding among high-risk women on ART in Burkina Faso.

METHODS

Plasma viral load (PVL) and enriched cervicovaginal lavage HIV-1 RNA were measured every 3-6 months for up to 8 years. Random-effects logistic and linear regression models were used to analyze associations of frequency and quantity of genital HIV-1 RNA with behavioral and biological factors, adjusting for within-woman correlation. The lower limit of detection of HIV-1 RNA in plasma and eCVL samples was 300 copies per milliliter.

RESULTS

One hundred and eighty-eight participants initiated ART from 2004 to 2011. PVL was detectable in 16% (171/1050) of visits, in 52% (90/174) of women. Cervicovaginal HIV-1 RNA was detectable in 16% (128/798) of visits with undetectable plasma HIV-1 RNA in 45% (77/170) of women. After adjusting for PVL, detectable cervicovaginal HIV-1 RNA was independently associated with abnormal vaginal discharge and use of nevirapine or zidovudine vs. efavirenz and stavudine, respectively; longer time on ART and hormonal contraception were not associated with increased shedding. The presence of bacterial vaginosis, herpes simplex virus-2 DNA, and the use of nevirapine vs efavirenz were independently associated with an increased quantity of cervicovaginal HIV-1 RNA.

CONCLUSIONS

Certain ART regimens, abnormal vaginal discharge, bacterial vaginosis, and genital herpes simplex virus-2 are associated with HIV-1 cervicovaginal shedding or quantity in women on ART after adjusting for PVL. This may reduce the effectiveness of ART as prevention in high-risk populations.

Presence of CD8+ T cells in the ectocervical mucosa correlates with genital viral shedding in HIV-infected women despite a low prevalence of HIV RNA-expressing cells in the tissue

The female genital tract is a portal of entry for sexual HIV transmission and a possible viral reservoir. In this study, the ectocervical CD8+ T cell distribution was explored in situ and was related to expression of CD3 and HLA-DR and presence of HIV RNA. For this purpose, ectocervical tissue samples and genital secretions were collected from HIV-seropositive (HIV+) Kenyan female sex workers (FSWs) (n = 20), HIV-seronegative (HIV-) FSWs (n = 17), and HIV(-) lower-risk women (n = 21). Cell markers were assessed by in situ staining and by quantitative PCR. HIV RNA expression in tissue was analyzed by in situ hybridization, and viral shedding was assessed by quantitative PCR. The HIV+ FSW group had a higher amount of total cells and CD8+, CD3+, and HLA-DR+ cells compared with the HIV(-)FSW group and HIV- lower-risk women. The majority of CD8+ cells were CD3+ T cells, and the numbers of CD8+ cells correlated significantly with plasma and cervical viral load. HIV RNA expression in situ was found in 4 of the 20 HIV+FSW women but did not correlate with cervical or plasma viral load. Thus, the HIV+ women displayed high numbers of CD8+, CD3+, and HLA-DR+ cells, as well as a limited number of HIV RNA+ cells, in their ectocervical mucosa; hence, this localization cannot be neglected as a potential viral reservoir. The elevated levels of CD8+ T cells may play a role in the immunopathogenesis of HIV in the female genital tract.

Association of plasma viremia with HIV-1 RNA levels in cervicovaginal lavage secretions in HIV-1 seropositive ART naïve women from Pune, India

BACKGROUND

Coherent drug/microbicide/vaccine development research would benefit through a precise knowledge of HIV dissemination and its persistence in the female genital tract. Understanding relationship between plasma viremia and cervicovaginal HIV shedding may help to unveil mechanisms underlying transmission, compartmentalization and pathogenesis.

OBJECTIVES

To study the association between HIV-1 RNA levels in the plasma and CVL specimens.

STUDY DESIGN

Whole blood, plasma and CVL specimens were collected from 36 ART naïve HIV-1 seropositive women qualifying the study inclusion criteria. Absolute CD4 counts, plasma and CVL HIV-1 RNA levels were estimated using commercially available kits (BD MultiSET™ Kit, Becton Dickinson, US and Abbott RT, Abbott Molecular, Germany). Correlation between plasma and CVL viral load was estimated by the Spearman's rank correlation coefficient. Additionally, the correlation between CVL viral load and absolute CD4 counts was studied.

RESULTS

HIV-1 viral load in the CVL specimens was successfully quantified using the Abbott RT. Twenty-seven of 36 women (75%) had detectable HIV-1 RNA levels in plasma and CVL specimens. The CVL viral load did not show any correlation with plasma viral load (ρ=0.281, p=0.096) and showed a 'moderate correlation' (ρ=-0.563, p=0.0004) with absolute CD4 counts.

CONCLUSIONS

Albeit, the Abbott RT is designed for estimating plasma HIV-1 RNA levels, the study reports its use for estimating HIV-1 RNA levels in the CVL specimens as well. In accordance with the previous studies, our results suggest that plasma and CVL viral load are not correlated and plasma viremia might not solely predict cervico vaginal HIV shedding.

Trichomoniasis and HIV interactions: a review

OBJECTIVE

To discuss the epidemiology of Trichomonas vaginalis (TV) and HIV co-infections, the role of TV in acquisition and transmission of HIV, special treatment considerations for TV among women with HIV and the prevention of TV among HIV-infected persons.

DESIGN

Systematic review.

DATA SOURCE

Review of literature of EMBASE and PubMed databases from January 1990 to February 2013. Search keywords included TV, HIV co-infections, HIV acquisition, HIV transmission, HIV shedding, TV treatment, HIV and couples studies.

REVIEW METHOD

We included studies of any design that contained the selected search words and were published during the specified time frame. We then searched the reference lists of included papers for additional papers and included these when relevant.

RESULTS

There is strong evidence that TV increases both transmission and acquisition of HIV among women, and that successful treatment for TV can reduce HIV genital shedding. Single dose metronidazole (MTZ) should no longer be used for HIV+ women with TV given the high rates of asymptomatic bacterial vaginosis co-infections and other factors that may render MTZ less effective in HIV+ women. Prevention of TV among HIV+ persons is similar to among HIV, including promotion of condoms as well as regular screening and prompt treatment. There may be a role for expedited partner treatment for the prevention of repeat infections, but most repeat infections are clinical treatment failures. Diligence in screening and treating TV among both HIV- susceptible and HIV+ persons is an important public health strategy.

Persistent genital tract HIV-1 RNA shedding after change in treatment regimens in antiretroviral-experienced women with detectable plasma viral load

OBJECTIVE

To longitudinally assess the association between plasma viral load (PVL) and genital tract human immunodeficiency virus (GT HIV) RNA among HIV-1 infected women changing highly active antiretroviral therapy (HAART) because of detectable PVL on current treatment.

METHODS

Women were eligible for the study if they had detectable PVL (defined as two consecutive samples with PVL>1000 copies/mL) and intended to change their current HAART regimen at the time of enrollment. Paired plasma and GT HIV-1 RNA were measured prospectively over 3 years. Longitudinal analyses examined rates of GT HIV-1 RNA shedding and the association with PVL.

RESULTS

Sixteen women were followed for a median of 11 visits contributing a total of 205 study visits. At study enrollment, all had detectable PVL and 69% had detectable GT HIV-1 RNA. Half of the women changed to a new HAART regimen with ≥3 active antiretroviral drugs. The probability of having detectable PVL ≥30 days after changing HAART was 0.56 (95% CI: 0.37 to 0.74). Fourteen women (88%) had detectable PVL on a follow-up visit ≥30 or 60 days after changing HAART; and 12 women (75%) had detectable GT HIV-1 RNA on a follow-up visit ≥30 or 60 days after changing HAART. When PVL was undetectable, GT shedding occurred at 11% of visits, and when PVL was detectable, GT shedding occurred at 47% of visits.

CONCLUSIONS

Some treatment-experienced HIV-infected women continue to have detectable virus in both the plasma and GT following a change in HAART, highlighting the difficulty of viral suppression in this patient population.

Cyclic changes in HIV shedding from the female genital tract during the menstrual cycle

Factors increasing genital human immunodeficiency virus (HIV) shedding may increase female-to-male HIV transmission risk. We examined HIV shedding in 67 women with HIV type 1 and herpes simplex virus type 2 coinfection, during 2 menstrual cycles. Shedding occurred in 60%, 48%, and 54% of samples during the follicular, periovulatory, and luteal phases, respectively (P = .01). Shedding declined after menses until ovulation, with a slope -0.054 log10 copies/swab/day (P < .001), corresponding to a change of approximately 0.74 log10 copies between peak and nadir levels. Shedding increased during the luteal phase only among women with CD4 counts of <350 cells/µL. In reproductive-aged women, shedding frequency and magnitude are greatest immediately following menses and lowest at ovulation.

Effect of trichomoniasis therapy on genital HIV viral burden among African women

BACKGROUND

Our objective was to test the hypothesis that treatment for trichomoniasis among HIV-infected women not taking antiretrovirals in South Africa would be associated with decreased HIV genital shedding.

METHODS

HIV-infected women presenting for routine HIV care were screened for trichomoniasis using self-collected vaginal swabs with a rapid point-of-care immunochromatographic antigen test. Women testing positive were offered enrollment into a prospective cohort study, if they had documented HIV infection, were aged 18 to 50 years, and were not receiving antiretroviral therapy. Recent use of postexposure prophylaxis or antibiotic therapy, active genital ulcers, or systemic illness were exclusion criteria. Cervical swabs were collected for gonococcal and chlamydial testing, and those testing positive were excluded. Women were treated with directly observed oral therapy with 2 g of oral metronidazole. A follow-up visit was scheduled 1 month after therapy, and partner letters were provided. Paired cervical wicks and plasma were collected for viral load measurement.

RESULTS

In all, 557 women were screened. Sixty tested positive for trichomoniasis, 10 subsequently met exclusion criteria, and 4 were lost to follow-up. Of 46 women evaluated at follow-up, 37 (80.4%) were cured. Plasma viral load was not significantly different after therapy (P = 0.93). Genital tract viral load decreased by 0.5 log10 (P < 0.01). The mean genital tract viral load (log10) decreased from 4.66 (<3.52-6.46) to 4.18 (<3.52-6.48) (P < 0.01) after therapy.

CONCLUSIONS

Screening and treatment of vaginal trichomoniasis decrease genital shedding of HIV among South African women not receiving antiretrovirals at 1 month after therapy.

Genital tract viral load in HIV Type 1-positive women correlates with specific cytokine levels in cervical-vaginal secretions but is not a determinant of infectious virus or anti-HIV activity

As the AIDS epidemic continues with women being disproportionately affected, it is crucial to understand factors that predict the risk of heterosexual HIV-1 transmission. We investigated whether genital tract viral load (GTVL) in cervical-vaginal lavages (CVL) from HIV-1-positive women with moderately low CD4 T cell counts correlates with cytokine levels, antimicrobial concentrations, and intrinsic anti-HIV activity. CVL were collected from 19 HIV-1-positive women with moderately low CD4 T cell counts [mean 381 cells/mm(3) (227-536 cells/mm(3))]. None of the women was on antiretroviral therapy. The women were categorized into those with detectable GTVL or those with undetectable GTVL (detectable GTVL RNA levels > 400 copies/ml). Women were also categorized according to bacterial vaginosis (BV) status irrespective of GTVL. The TZM-bl assay was used to determine the presence of infectious virus and anti-HIV activity. Significantly higher levels of RANTES, Eotaxin, Fractalkine, IL-1α, IL-6, MCP-1, MIP1β, MIP1α, TNF-α, and GM-CSF were observed in women with detectable GTVL compared to women with undetectable GTVL. No significant differences were observed in the following cytokines and chemokines: G-CSF, IL-1RA, IL-8, and IP-10. GTVL did not correlate either with antimicrobials known to have anti-HIV activity or with the presence of infectious virus. BV status did not have a significant effect on anti-HIV activity. These findings further our understanding of the role of GTVL in determining the cytokine and chemokine milieu in the female reproductive tract.

Permissive and protective factors associated with presence, level, and longitudinal pattern of cervicovaginal HIV shedding

BACKGROUND

Cervicovaginal HIV level (CV-VL) influences HIV transmission. Plasma viral load (PVL) correlates with CV-VL, but discordance is frequent. We evaluated how PVL, behavioral, immunological, and local factors/conditions individually and collectively correlate with CV-VL.

METHODS

CV-VL was measured in the cervicovaginal lavage fluid (CVL) of 481 HIV-infected women over 976 person-visits in a longitudinal cohort study. We correlated identified factors with CV-VL at individual person-visits and detectable/undetectable PVL strata by univariate and multivariate linear regression and with shedding pattern (never, intermittent, persistent ≥3 shedding visits) in 136 women with ≥3 visits by ordinal logistic regression.

RESULTS

Of 959 person-visits, 450 (46.9%) with available PVL were discordant, 435 (45.3%) had detectable PVL with undetectable CV-VL, and 15 (1.6%) had undetectable PVL with detectable CV-VL. Lower CV-VL correlated with highly active antiretroviral therapy (HAART) usage (P = 0.01). Higher CV-VL correlated with higher PVL (P < 0.001), inflammation-associated cellular changes (P = 0.03), cervical ectopy (P = 0.009), exudate (P = 0.005), and trichomoniasis (P = 0.03). In multivariate analysis of the PVL-detectable stratum, increased CV-VL correlated with the same factors and friability (P = 0.05), while with undetectable PVL, decreased CV-VL correlated with HAART use (P = 0.04). In longitudinal analysis, never (40.4%) and intermittent (44.9%) shedding were most frequent. Higher frequency shedders were more likely to have higher initial PVL [odds ratio (OR) = 2.47/log10 increase], herpes simplex virus type 2 seropositivity (OR = 3.21), and alcohol use (OR = 2.20).

CONCLUSIONS

Although PVL correlates strongly with CV-VL, discordance is frequent. When PVL is detectable, cervicovaginal inflammatory conditions correlate with increased shedding. However, genital shedding is sporadic and not reliably predicted by associated factors. HAART, by reducing PVL, is the most reliable means of reducing cervicovaginal shedding.

Pharmacokinetics of antiretroviral drugs in anatomical sanctuary sites: the male and female genital tract

HIV resides within anatomical 'sanctuary sites', where local drug exposure and viral dynamics may differ significantly from the systemic compartment. Suboptimal antiretroviral concentrations in the genital tract may result in compartmentalized viral replication, selection of resistant mutations and possible re-entry of wild-type/resistant virus into the systemic circulation. Therefore, achieving adequate antiretroviral exposure in the genital tract has implications for the prevention of sexual and vertical transmission of HIV. Penetration of antiretrovirals in the genital tract is expressed by accumulation ratios derived from the measurement of drug concentrations in time-matched seminal plasma/cervicovaginal fluid and plasma samples. Penetration varies by gender and may be drug (as opposed to class) specific with high interindividual variability. Concentrations in seminal plasma are highest for nucleoside analogues and lowest for protease inhibitors and efavirenz. Seminal accumulation of newer agents, raltegravir and maraviroc, is moderate (rank order of accumulation is nucleoside/nucleotide reverse transcriptase inhibitors [lamivudine/zidovudine/tenofovir/didanosine > stavudine/abacavir] > raltegravir > indinavir/maraviroc/nevirapine >> efavirenz/protease inhibitors [amprenavir/atazanavir/darunavir > lopinavir/ritonavir > saquinavir] > enfuvirtide). In the female genital tract, the nucleoside analogues exhibit high accumulation ratios, whereas protease inhibitors have limited penetration; however, substantial variability exists between individuals and study centres. Second generation non-nucleoside reverse transcriptase inhibitor etravirine, and maraviroc and raltegravir, demonstrate effective accumulation in cervicovaginal secretions (rank order of accumulation is nucleoside/nucleotide reverse transcriptase inhibitor [zidovudine/lamivudine/didanosine > emtricitabine/tenofovir] > indinavir > maraviroc/raltegravir/darunavir/etravirine > nevirapine/abacavir > protease inhibitors [amprenavir/atazanavir/ritonavir] > lopinavir/stavudine/efavirenz > saquinavir).

Residual HIV-1 RNA and HIV-1 DNA production in the genital tract reservoir of women treated with HAART: the prospective ANRS EP24 GYNODYN study

BACKGROUND

The female genital tract constitutes a reservoir for HIV providing active production of both cell-free HIV RNA and cell-associated DNA within the cervicovaginal secretions. The objective of this study was to prospectively assess residual HIV-1 RNA and HIV-1 DNA production in the genital tract reservoir of women initiating HAART over an 18-month period.

METHODS

Paired blood and cervicovaginal lavage samples were collected at inclusion and 1, 6, 12 and 18 months after HAART initiation, in 23 women in first-line HAART and six women in virological failure, for measurement of HIV-1 RNA and HIV-1 DNA shedding and/or drug concentrations.

RESULTS

A dramatic decrease of HIV-1 RNA and HIV-1 DNA occurred in both blood and cervicovaginal samples over the first 6 months on HAART, followed by a shelf up to 18 months, independently of the drugs' genital pharmacokinetics. While cervicovaginal HIV-1 RNA became undetectable in >90% of women from 6 months on HAART, genital HIV-1 DNA remained frequently detectable (27-50%). Nearly 40% of women with sustained undetectable plasma HIV-1 RNA after 6-18 months on HAART harboured transient HIV-1 RNA (15% of women) or HIV-1 DNA (31% of women) in their genital secretions.

CONCLUSIONS

Low-level cervicovaginal HIV-1 shedding is frequently evidenced in HAART-treated women with transient HIV-1 RNA and persistent HIV-1 DNA despite a systemic control of viral replication, resulting in possible residual genital infectivity.

Parametric variable selection in generalized partially linear models with an application to assess condom use by HIV-infected patients

To study significant predictors of condom use in HIV-infected adults, we propose the use of generalized partially linear models and develop a variable selection procedure incorporating a least squares approximation. Local polynomial regression and spline smoothing techniques are used to estimate the baseline nonparametric function. The asymptotic normality of the resulting estimate is established. We further demonstrate that, with the proper choice of the penalty functions and the regularization parameter, the resulting estimate performs as well as an oracle procedure. Finite sample performance of the proposed inference procedure is assessed by Monte Carlo simulation studies. An application to assess condom use by HIV-infected patients gains some interesting results, which cannot be obtained when an ordinary logistic model is used.

Change in sexual activity 12 months after ART initiation among HIV-positive Mozambicans

We assessed sexual behaviors before and 12-months after ART initiation among 277 Mozambicans attending an HIV clinic. Measured behaviors included the number of sexual partners, condom use, concurrent relationships, disclosure of HIV status, alcohol use, and partners' serostatus. Compared to before ART initiation, increases were seen 12 months after ART in the proportion of participants who were sexually active (48% vs. 64% respondents, P < 0.001) and the proportion of participants with HIV-negative or unknown serostatus partners (45% vs. 80%, P < 0.001). Almost all (96%) concurrent partnerships reported at 12 months formed after ART initiation. Although reported correct and consist condom use increased, the number of unprotected sexual relationships remained the same (n = 45). Non-disclosure of HIV-serostatus to sexual partners was the only significant predictor of practicing unprotected sex with partners of HIV-negative or unknown serostatus. Sexual activity among HIV-positive persons on ART increased 12 months after ART initiation. Ongoing secondary transmission prevention programs addressing sexual activity with multiple partners, disclosure to partners and consistent condom use with serodisconcordant partners must be incorporated throughout HIV care programs.

Clinical parameters essential to methodology and interpretation of mucosal responses

Research aimed at putting an end to the HIV pandemic is dynamic given the marked advances in understanding of pathogenesis since its origin. Attention has shifted from systemic management of disease to a focus on the most common site of acquisition, the female genital tract. Research on the female genital tract of humans requires consideration of a number of specific clinical parameters. If such parameters are not considered when enrolling subjects into studies, it could lead to faulty data ascertainment. This article reviews important clinical characteristics to consider when conducting studies of the human female genital tract in regard to mucosal immunity and HIV disease. Important topics to consider include the method and source of sample collection, the individual patient characteristics, and in the case of recruitment of HIV-infected women, HIV disease characteristics.

Antiretroviral therapy: a promising HIV prevention strategy?

The use of antiretroviral therapy (ART) has been associated with significant improvement in morbidity and survival of persons living with HIV. In addition, recently, there has also been intense interest in the potential impact of ART on HIV transmission and consequently on the trajectory of the HIV epidemic globally. Evidence from mathematical modeling analyses and observational and ecological studies supports the potential for ART as prevention. However, definitive data from clinical trials are awaited. In the United States, the feasibility and potential of using ART as a prevention strategy presents particular challenges: the large number of individuals with undiagnosed HIV; the predominance of disenfranchised individuals affected by the epidemic; evidence of delay in engagement in HIV care after diagnosis with attendant late initiation of ART; and difficulties with consistent long-term adherence to ART and concerns regarding long-term risk-behavior change. Thus, for this novel effort to succeed, a multidimensional approach is necessary that must include policy changes, social mobilization, and improved access to clinical and supportive services for persons living with HIV, with a particular focus on the unique needs of at-risk populations, combined with engagement of all cadres of health care providers and community constituencies.

Genital tract HIV-1 RNA shedding among women with below detectable plasma viral load

OBJECTIVE

Few studies have assessed longitudinal genital tract HIV-1 shedding. We determined patterns of genital tract HIV-1 RNA shedding over time among women with suppressed plasma viral load (PVL) on antiretroviral treatment.

METHODS

Paired plasma and genital tract HIV-1 RNA were measured every 4 weeks. Participants were classified as persistent, intermittent, or nonshedders. Longitudinal analysis examined rates of genital tract shedding and the association with PVL, CD4 cell count, and genital tract infections. Markov transition models were used to describe the dynamics of HIV-1 RNA in plasma and genital tract using visit-to-visit transitions from and to detectable and undetectable PVL or genital tract HIV-1 RNA.

RESULTS

Fifty-nine women contributed 582 study visits of whom 95 and 98% had below-detectable PVL and genital tract viral load, respectively, at baseline. Thirty-two of 59 women (54%) had detectable HIV-1 RNA at least once in the genital tract. Twenty-two of 59 (37%) women had detectable genital tract HIV-1 RNA during a study visit when PVL was undetectable; 6.8% of the women were persistent shedders, 31% were intermittent shedders, and 45.8% were nonshedders. Sampling three subcompartments increased detection of HIV-1 genital tract viral load compared to sampling a single subcompartment. Overall, genital tract HIV-1 RNA shedding in any subcompartment occurred at about 13% of visits. Shedding in at least one of the three subcompartments occurred at 9% of visits when PVL was undetectable (95% confidence interval 6-14%).

CONCLUSION

Women with below-detectable PVL may have less risk of HIV sexual transmission on a population level, but may continue to be infectious on an individual level.

Anti-HIV activity in cervical-vaginal secretions from HIV-positive and -negative women correlate with innate antimicrobial levels and IgG antibodies

Background

We investigated the impact of antimicrobials in cervicovaginal lavage (CVL) from HIV(+) and HIV(−) women on target cell infection with HIV. Since female reproductive tract (FRT) secretions contain a spectrum of antimicrobials, we hypothesized that CVL from healthy HIV(+) and (−) women inhibit HIV infection.

Methodology/Principal Findings

CVL from 32 HIV(+) healthy women with high CD4 counts and 15 healthy HIV(−) women were collected by gently washing the cervicovaginal area with 10 ml of sterile normal saline. Following centrifugation, anti-HIV activity in CVL was determined by incubating CVL with HIV prior to addition to TZM-bl cells. Antimicrobials and anti-gp160 HIV IgG antibodies were measured by ELISA. When CXCR4 and CCR5 tropic HIV-1 were incubated with CVL from HIV(+) women prior to addition to TZM-bl cells, anti-HIV activity in CVL ranged from none to 100% inhibition depending on the viral strains used. CVL from HIV(−) controls showed comparable anti-HIV activity. Analysis of CH077.c (clone of an R5-tropic, mucosally-transmitted founder virus) viral inhibition by CVL was comparable to laboratory strains. Measurement of CVL for antimicrobials HBD2, trappin-2/elafin, SLPI and MIP3α indicated that each was present in CVL from HIV(+) and HIV(−) women. HBD2 and MIP3α correlated with anti-HIV activity as did anti-gp160 HIV IgG antibodies in CVL from HIV(+) women.

Conclusions/Significance

These findings indicate that CVL from healthy HIV(+) and HIV(−) women contain innate and adaptive defense mechanisms that inhibit HIV infection. Our data suggest that innate endogenous antimicrobials and HIV-specific IgG in the FRT can act in concert to contribute toward the anti-HIV activity of the CVL and may play a role in inhibition of HIV transmission to women.

Does antiretroviral therapy prevent HIV transmission to sexual partners?

The majority of HIV-1 infections are acquired sexually, and interventions to prevent sexual transmission are urgently needed to curb the growth of the HIV pandemic. The potential role of antiretroviral therapy in preventing sexual transmission of HIV is still emerging. Highly active antiretroviral therapy has been shown to decrease HIV RNA shedding in the genital tract, and its use among serodiscordant couples has been associated with reduced seroconversions in partners who are HIV negative. However, other studies have associated the use of antiretroviral therapy with increased HIV transmission risk behaviors. In this review, we explore the rationale for using highly active antiretroviral therapy to prevent sexual transmission of HIV including its role in prevention strategies at the population level, as well as the cost-effectiveness and potential limitations of this approach.

Antiretrovirals to prevent HIV infection: pre- and postexposure prophylaxis

More than 3 million people are now receiving antiretroviral therapy (ART) worldwide. Currently, the indications for ART depend primarily on CD4 count, blood viral burden, and clinical signs and symptoms suggesting advanced HIV disease. However, interest is increasing in ART's preventive potential. Postexposure prophylaxis following both occupational and nonoccupational exposure to HIV is the standard-of-care in many settings. Observational and ecologic studies suggest that ART administered to HIV-infected people reduces transmission within serodiscordant couples. Pre-exposure prophylaxis to prevent HIV infection is a potentially safe and intermittent intervention for very high-risk people, and clinical trials to evaluate this preventive strategy are underway. The prevention benefits of ART may begin to affect the decision of when to start therapy and add a much-needed strategy to current HIV prevention efforts.

Treatment to prevent transmission of HIV-1

Antiretroviral therapy (ART) has the potential to prevent human immunodeficiency virus (HIV) transmission by reducing the concentration of HIV in blood and genital secretions. Indeed, mathematical models with favorable assumptions suggest the potential of ART to stop the spread of HIV infection. Empirical results from ecological and population-based studies and from several short-term observational studies involving HIV status-discordant heterosexual couples suggest that ART reduces the rate of HIV transmission. A multinational, randomized, controlled trial (National Institutes of Health HPTN052) examining the reliability and durability of ART as prevention of transmission in HIV status-discordant couples is under way. The latter and other studies also consider sexual risk-taking behavior and transmission of HIV-resistant variants when ART is used as prevention. Early HIV detection and treatment (ie, test and treat) are being considered as an important prevention strategy. In this article, we review the data supporting the use of ART to prevent HIV transmission and critically examine the public health implications of this strategy.

Plasma and cervical viral loads among Ugandan and Zimbabwean women during acute and early HIV-1 infection

OBJECTIVES

High levels of HIV-1 viremia exist in peripheral blood during acute and early infection; however, data on HIV-1 viral loads in female genital secretions during this period are sparse.

DESIGN

Prospective cohort of 188 African women with primary HIV-1 infection.

METHODS

HIV-uninfected and infected women were followed quarterly; we tested serial plasma specimens by HIV PCR to estimate infection dates. We used the Loess procedure to estimate the magnitude and timing of viral setpoints in plasma and cervical secretions and generalized estimating equations (GEE) to identify predictors of plasma and cervical viral setpoints.

RESULTS

We estimated the mean HIV-1 plasma setpoint to be 4.20 log10 HIV-1 RNA copies/ml [95% confidence interval (CI) 4.04-4.35] at 121 days (95% CI 91-137) from infection; an analogous mean cervical viral setpoint was 1.64 log10 HIV-1 RNA copies/swab (95% CI 1.46-1.82) at 174 days (95% CI 145-194) from infection. Cervical loads were significantly higher (0.7-1.1 log10 copies/swab) during acute infection than subsequently. Subtype D infection, pregnancy, breastfeeding, and older age at the time of infection were associated with higher plasma viral setpoint. Subtype C infection, nonviral sexually transmitted infections, having a partner spending nights away from home, recent unprotected sex, and shorter time since infection were associated with higher cervical HIV-1 loads. Hormonal contraception was not associated with either the HIV-1 plasma setpoint or cervical loads during early infection.

CONCLUSION

Cervical HIV-1 viral loads were highest during acute infection and then declined up to 6 months following infection, when a 'setpoint' was attained. The prognostic value of a cervical 'setpoint' on future transmission risk remains unclear.

Detection of fastidious vaginal bacteria in women with HIV infection and bacterial vaginosis

BACKGROUND

Fastidious bacteria have been associated with bacterial vaginosis (BV) using PCR methods. We assessed the prevalence of these bacteria in HIV-1 infected women and their relationship with vaginal pH and shedding of HIV-1 RNA.

METHODS

64 cervicovaginal lavage (CVL) samples were collected from 51 women. Vaginal microbiota were characterized using 8 bacterium-specific quantitative PCR assays.

RESULTS

Women with the fastidious bacteria Bacterial Vaginosis Associated Bacterium (BVAB) 1, 2, and 3 showed a trend to increased HIV-1 shedding (OR 2.59-3.07, P = .14-.17). Absence of Lactobacillus crispatus (P < .005) and presence of BVAB2 (P < .001) were associated with elevated vaginal pH. BVAB1, 2, and 3 were highly specific indicators of BV in HIV-infected women, with specificities of 89%-93%.

CONCLUSIONS

Fastidious bacteria (BVAB 1, 2, and 3) remain specific indicators of BV in HIV-infected women, and BVAB2 may contribute to the elevated vaginal pH that is a hallmark of this syndrome.

Potential impact of early antiretroviral therapy on transmission

PURPOSE OF REVIEW

In this review, we will discuss the potential of early highly active antiretroviral therapy (HAART) to reduce the sexual transmission of HIV on an individual and population level. We will focus on the biological plausibility and behavioural factors associated with HAART use and interventions that might influence such a strategy.

RECENT FINDINGS

Empiric and phylogenetic studies support the view that recent HIV infection is a highly infectious disease stage. Evidence increasingly demonstrates that individuals on fully suppressive HAART are significantly less likely to transmit HIV to sexual partners and some even suggest that such individuals cannot transmit HIV. Changes in risk behaviour are associated with the availability of HAART but behavioural studies offer contradictory observations regarding the direction and magnitude of these changes. This in turn makes the intricate assumptions and therefore outcomes of many complex mathematical modelling studies less secure. Furthermore, there is evidence that it is those individuals with undiagnosed HIV infection who contribute significantly to onward sexual transmission.

SUMMARY

At an individual level, HAART will reduce viral load and, therefore, infectiousness, although whether to zero or not remains controversial. At a population level, if recent infection and undiagnosed infections continue to drive onward transmission, earlier treatment will only alter the pandemic if accompanied by an improvement in diagnosing the undiagnosed and recognizing recent infection.

The effect of genital tract infections on HIV-1 shedding in the genital tract: a systematic review and meta-analysis

This article reviews the effect of genital tract infections and associated clinical conditions on the detection and concentration of HIV-1 shedding in the genital tract. A search of the PubMed, Embase, and AIDSearch databases was conducted. Meta-analysis was performed on those studies that reported the effect of genital tract infections on the detection of HIV-1 shedding. Thirty-nine studies met the inclusion criteria. The odds of HIV-1 detection in the genital tract were increased most substantially by urethritis (OR 3.1, 95% CI: 1.1-8.6) and cervicitis (OR 2.7, 95% CI: 1.4-5.2). The odds of HIV-1 detection were also increased significantly in the presence of cervical discharge or mucopus (OR 1.8, 95% CI: 1.2-2.7), gonorrhoea (OR 1.8, 95% CI: 1.2-2.7), chlamydial infection (OR 1.8, 95% CI: 1.1-3.1), and vulvovaginal candidiasis (OR 1.8, 95% CI: 1.3-2.4). Other infections and clinical conditions were found to have no significant effect on the detection of HIV-1, although HSV-2 shedding was found to increase the concentration of HIV-1 shedding, and genital ulcer disease was found to increase the odds of HIV-1 detection significantly after excluding one biased study (OR 2.4, 95% CI: 1.2-4.9). This analysis shows that infections that are associated with significant increases in leukocyte concentrations in the genital tract are also associated with significant increases in HIV-1 shedding. These infections are likely to be particularly important in promoting the sexual transmission and mother-to-child intrapartum transmission of HIV-1, and should therefore be the focus of HIV prevention strategies.

Genital tract leukocytes and shedding of genital HIV type 1 RNA

BACKGROUND

The mechanism of human immunodeficiency virus (HIV) transmission via heterosexual intercourse is unknown. We sought to determine whether the presence of inflammatory cells in the vagina is associated with the presence of genital tract HIV type 1 (HIV-1) RNA.

METHODS

Analysis of a longitudinal prospective cohort was performed. Women with HIV-1 infection were assessed with use of paired plasma and cervicovaginal lavage specimens. Viral load measurements were performed using nucleic acid sequence-based amplification. White blood cells found in the genital tract (GT WBCs) were quantified using a hemacytometer. Common lower genital tract infections assessed for association with viral shedding (i.e., genital tract viral load [GTVL]) included bacterial vaginosis, candidiasis, and trichomoniasis. Generalized estimating equations were used to estimate the prevalence and odds of detectable GTVL by GT WBC. The association was examined both in the presence and in the absence of lower genital tract infections.

RESULTS

A total of 97 women and 642 visits were included in the analysis. Median duration of follow-up was 30.4 months. Thirty women (31%) had detectable GTVL at any visit. The median CD4 cell count at baseline was 525 cells/muL. Most women were antiretroviral therapy naive at baseline. After adjustment for plasma viral load, the odds of detectable GTVL increased as GT WBC increased, with an odds ratio of 1.36 (95% confidence interval, 1.1-1.7) per 1000-cell increase in GT WBC among women without lower genital tract infections. After adjustment for plasma viral load and lower genital tract infections by incorporating them in a regression model, GT WBC remained significantly associated with GTVL, with an adjusted odds ratio of 1.22 (95% confidence interval, 1.08-1.37).

CONCLUSIONS

The presence of GT WBC is associated with an increased risk of detectable GTVL.

Antiretroviral drug concentrations and HIV RNA in the genital tract of HIV-infected women receiving long-term highly active antiretroviral therapy

OBJECTIVE

Our objective was to determine antiretroviral drug concentrations and human immunodeficiency virus (HIV) RNA rebound in cervicovaginal fluid (CVF) in relation to blood plasma (BP) in women receiving suppressive highly active antiretroviral therapy (HAART).

METHODS

Thirty-four HIV-infected women who had plasma HIV RNA levels < or =80 copies/mL for at least 6 months were enrolled. Sixty-eight paired CVF and BP drug concentrations and HIV RNA levels were determined before and 3-4 h after drug administration. For each woman and antiretroviral drug, the CVF:BP drug concentration ratios before and after drug administration were calculated. The nonparametric Wilcoxon rank sum test was used to determine if these ratios were different from 1.0.

RESULTS

Lamivudine (administered to 20 patients) and tenofovir (administered to 16) had significantly higher concentrations in CVF than in BP before drug administration, with mean CVF:BP concentration ratios of 3.19 (95% confidence interval, 1.2-8.5) and 5.2 (95% confidence interval, 1.2-22.6), respectively. Efavirenz (administered to 13 patients) and lopinavir (administered to 6) had significantly lower concentrations in CVF, with mean CVF:BP concentration ratios of 0.01 (95% confidence interval, 0.00-0.03) and 0.03 (0.01-0.11), respectively. During the study visit (median time after enrollment, 6 months), BP and CVF detectable HIV RNA levels were observed 7 patients (20.6%) and 1 patient (2.9%), respectively.

CONCLUSION

Despite lower CVF concentrations of key HAART components, such as efavirenz and lopinavir, virologic rebound was rare. The high concentrations of tenofovir and lamivudine in CVF may have implications for the prevention of sexual transmission during HAART and for pre-exposure or postexposure prophylaxis.

Does antiretroviral therapy prevent HIV transmission to sexual partners?

The majority of HIV-1 infections are acquired sexually, and interventions to prevent sexual transmission are urgently needed to curb the growth of the HIV pandemic. The potential role of antiretroviral therapy in preventing sexual transmission of HIV is still emerging. Highly active antiretroviral therapy has been shown to decrease HIV RNA shedding in the genital tract, and its use among serodiscordant couples has been associated with reduced seroconversions in partners who are HIV negative. However, other studies have associated the use of antiretroviral therapy with increased HIV transmission risk behaviors. In this review, we explore the rationale for using highly active antiretroviral therapy to prevent sexual transmission of HIV including its role in prevention strategies at the population level, as well as the cost-effectiveness and potential limitations of this approach.