Recent observations on HIV type-1 infection in the genital tract of men and women

Effects of Ginger on Disgust, Sexual Arousal, and Sexual Engagement: A Placebo-Controlled Experiment

Sexual problems are common complaints across countries and cultures, and behavioral immune system theory suggests disgust plays an essential role in sexual functioning. The current study investigated 1) if disgust induced by sexual body fluids would reduce sexual arousal, reduce the likelihood of sexual engagement, and enhance disgust toward subsequent erotic stimuli, and 2) if the administration of ginger would affect these reactions. We administered either ginger or placebo pills to a sample of 247 participants (Mage = 21.59, SD = 2.52; 122 women) and asked them to complete either behavioral approach tasks with sexual body fluids or with neutral fluids. Next, participants viewed and responded to questions concerning erotic stimuli (nude and seminude pictures of opposite-sex models). As expected, the sexual body fluids tasks induced disgust. The elevated disgust induced by sexual body fluids tasks resulted in lower sexual arousal in women, whereas ginger consumption counteracted this inhibiting effect of disgust on sexual arousal. Disgust elicited by sexual body fluids also increased disgust toward the subsequent erotic stimuli. Ginger increased sexual arousal toward the erotic stimuli in both men and women who had completed the neutral fluids tasks. Findings provide further evidence of the role of disgust in sexual problems, and, importantly, that ginger may improve the sexual function of individuals via its sexual arousal-enhancing effect.

Acute Infectious Proctitis in Adolescents

The diagnosis of acute proctitis requires understanding who is at risk, being aware of symptoms, and leveraging a thorough sexual history with appropriate risk stratification to make the diagnosis. Cases have been concentrated in adolescents (ages 15-19 years), young adults (ages 20-24 years), men and transgender women who have sex with men, and those with a history of human immunodeficiency virus infection. Black adolescents experience a disproportionately high number of cases of proctitis due to an intersection of concentrated cases in sexual networks and delayed screening/diagnosis due to health care access barriers. Signs and symptoms include purulent discharge, bleeding, pain, tenesmus, pruritus, diarrhea or constipation, weight loss, or fever. Multisite sexually transmitted infection testing should be offered based on risk stratification (eg, history of condomless anal sex, oral intercourse, number of sex partners). Further management includes promotion of barrier protection and preexposure prophylaxis, routine surveillance, partner notification, and routine access to preventive immunizations.

EFdA efficiently suppresses HIV replication in the male genital tract and prevents penile HIV acquisition

Sexually transmitted HIV infections in heterosexual men are acquired through the penis. Low adherence to condom usage and the fact that 40% of circumcised men are not protected indicate the need for additional prevention strategies. Here, we describe a new approach to evaluate the prevention of penile HIV transmission. We demonstrated that the entire male genital tract (MGT) of bone marrow/liver/thymus (BLT) humanized mice is repopulated with human T and myeloid cells. The majority of the human T cells in the MGT express CD4 and CCR5. Direct penile exposure to HIV leads to systemic infection including all tissues of the MGT. HIV replication throughout the MGT was reduced 100-1,000-fold by treatment with 4'-ethynyl-2-fluoro-2'-deoxyadenosine (EFdA), resulting in the restoration of CD4+ T cell levels. Importantly, systemic preexposure prophylaxis with EFdA effectively protects from penile HIV acquisition. IMPORTANCE Over 84.2 million people have been infected by the human immunodeficiency virus type 1 (HIV-1) during the past 40 years, most through sexual transmission. Men comprise approximately half of the HIV-infected population worldwide. Sexually transmitted HIV infections in exclusively heterosexual men are acquired through the penis. However, direct evaluation of HIV infection throughout the human male genital tract (MGT) is not possible. Here, we developed a new in vivo model that permits, for the first time, the detail analysis of HIV infection. Using BLT humanized mice, we showed that productive HIV infection occurs throughout the entire MGT and induces a dramatic reduction in human CD4 T cells compromising immune responses in this organ. Antiretroviral treatment with novel drug EFdA suppresses HIV replication in all tissues of the MGT, restores normal levels of CD4 T cells and is highly efficient at preventing penile transmission.

Bidirectional relationship between sexual arousal and (sex-related) disgust

Sexual stimuli provoke both sexual arousal and disgust, and the coaction between these emotions determines sexually behavioral outcomes. The current research includes two experiments to explore the bidirectional relationship between sexual arousal toward erotic stimuli and disgust induced by sexual body fluids. Study 1 presented 234 participants (117 women) with sexual body (vs. neutral) fluids followed by erotic stimuli, and Study 2 presented 235 participants (117 women) with erotic (vs. neutral) videos followed by sexual body fluids (and a non-sex-related stimulus). Study 1 showed that exposure to sexual body fluids reduced sexual arousal and the likelihood of sexual engagement toward erotic stimuli in participants with high sexual disgust sensitivity but increased sexual arousal and the likelihood of sexual engagement in participants with low sexual disgust sensitivity, while Study 2 suggested that men exposed to erotic (vs. neutral) stimuli reported lower disgust, stronger sexual arousal state, and higher willingness to interact with the sexual body fluids. There was no relationship between subjective feelings of sexual arousal and disgust in these experiments, while the balance of sexual arousal and disgust toward sexual body fluids and erotic stimuli had a positive association. Also, exposure to erotic stimuli had no effect on reactions to generally disgusting stimulus, but feelings of sexual arousal toward erotic stimuli were positively associated with disgust induced by generally disgusting fluid. These findings suggest that Behavior Immune System regulates disgust to establish a balance between benefit and cost related to sex as well as provide insight into the process underlying sexual dysfunctions.

The Neisseria gonorrhoeae type IV pilus promotes resistance to hydrogen peroxide- and LL-37-mediated killing by modulating the availability of intracellular, labile iron

The Neisseria gonorrhoeae Type IV pilus is a multifunctional, dynamic fiber involved in host cell attachment, DNA transformation, and twitching motility. We previously reported that the N. gonorrhoeae pilus is also required for resistance against hydrogen peroxide-, antimicrobial peptide LL-37-, and non-oxidative, neutrophil-mediated killing. We tested whether the hydrogen peroxide, LL-37, and neutrophil hypersensitivity phenotypes in non-piliated N. gonorrhoeae could be due to elevated iron levels. Iron chelation in the growth medium rescued a nonpiliated pilE mutant from both hydrogen peroxide- and antimicrobial peptide LL-37-mediated killing, suggesting these phenotypes are related to iron availability. We used the antibiotic streptonigrin, which depends on free cytoplasmic iron and oxidation to kill bacteria, to determine whether piliation affected intracellular iron levels. Several non-piliated, loss-of-function mutants were more sensitive to streptonigrin killing than the piliated parental strain. Consistent with the idea that higher available iron levels in the under- and non-piliated strains were responsible for the higher streptonigrin sensitivity, iron limitation by desferal chelation restored resistance to streptonigrin in these strains and the addition of iron restored the sensitivity to streptonigrin killing. The antioxidants tiron and dimethylthiourea rescued the pilE mutant from streptonigrin-mediated killing, suggesting that the elevated labile iron pool in non-piliated bacteria leads to streptonigrin-dependent reactive oxygen species production. These antioxidants did not affect LL-37-mediated killing. We confirmed that the pilE mutant is not more sensitive to other antibiotics showing that the streptonigrin phenotypes are not due to general bacterial envelope disruption. The total iron content of the cell was unaltered by piliation when measured using ICP-MS suggesting that only the labile iron pool is affected by piliation. These results support the hypothesis that piliation state affects N. gonorrhoeae iron homeostasis and influences sensitivity to various host-derived antimicrobial agents.

Neisseria gonorrhoeae is a bacterium that causes the sexually transmitted infection, gonorrhea. The bacteria express a fiber on their surface called a pilus that mediates many interactions of the bacterial cell with host cells and tissues. The ability to resist killing by white cells is one important ability that N. gonorrhoeae uses to allow infection of otherwise healthy people. We show here that the pilus help resist white cell killing by modulating the levels of iron within the bacterial cell.

Sexually transmitted infection associated syndromes among pregnant women attending antenatal care clinics in southwest Ethiopia

Background

Sexually transmitted infections (STIs) are widely reported in pregnant women in Africa and can cause significant maternal and perinatal morbidity. The availability of epidemiologic data on STIs and their associated factors in pregnant women is critical to developing effective prevention strategies. Therefore, this study aimed to assess the prevalence and factors associated with sexually transmitted infection-associated syndromes among pregnant women attending antenatal care clinics at selected public health facilities in southwest Ethiopia.

Methods

A cross-sectional study was carried out with 303 pregnant women who attended ANC between November 1 and 30, 2018. The consecutive sampling technique was employed until the required sample size was reached. The data were collected using a structured and pre-tested questionnaire. Bi-variable and multivariate logistic regressions were used to identify independent variables associated with the outcome of interest. The level of significance was declared at a p-value < 0.05.

Results

Of the 303 respondents surveyed, STI-associated syndromes had a prevalence of 19.1% (95% CI: 14.7%–23.5%). Nearly one-tenth (8.9%) of the respondents had vaginal discharge syndrome followed by lower abdominal or pelvic pain (7.6%). The study also found that being unmarried (AOR = 5.61, 95% CI [2.34–9.36]), not formally educated (AOR = 2.24, 95% CI [1.58–3.86]), having multiple sexual partners in the past 3 months (AOR = 3.93, 95% CI [1.44–5.23]), history of spontaneous abortion (AOR = 4.48, 95% CI [2.21–7.72]), and history of STI (AOR = 3.76, 95% CI [2.24–6.46]) were the factors associated with STI-associated syndromes.

Conclusion

The prevalence of STI-associated syndromes among respondents was 19.1%. The study found that being unmarried, not formally educated, having multiple sexual partners, history of spontaneous abortion, and history of STI were largely accountable for the occurrence of STI-associated syndromes in the study sample. Therefore, in addition to the one-time assessment of HIV and syphilis at the first ANC visit, there is a need to emphasize the syndromic approach diagnosis of STIs among pregnant women during each ANC visit to reduce and ultimately prevent both vertical and horizontal transmissions of STIs.

How do biases in sex ratio and disease characteristics affect the spread of sexually transmitted infections?

The epidemiology of sexually transmitted infections (STIs) is inherently linked to host mating dynamics. Studies across many taxa show that adult sex ratio, a major determinant of host mating dynamics, is often skewed - sometimes strongly - toward males or females. However, few predictions exist for the effects of skewed sex ratio on STI epidemiology, and none when coupled with sex biased disease characteristics. Here we use mathematical modelling to examine how interactions between sex ratio and disease characteristics affect STI prevalence in males and females. Notably, we find that while overall disease prevalence peaks at equal sex ratios, prevalence per sex peaks at skewed sex ratios. Furthermore, disease characteristics, sex-biased or not, drive predictable differences in male and female STI prevalence as sex ratio varies, with higher transmission and lower virulence generally increasing differences between the sexes for a given sex ratio. Our work reveals new insights into how STI prevalence in males and females depends on a complex interaction between host population sex ratio and disease characteristics.

Microbial mismanagement: how inadequate treatments for vaginal dysbiosis drive the HIV epidemic in women

Women and girls represent a key population driving new HIV infections and persistence of the HIV pandemic. A key determinant of HIV susceptibility is the composition of the vaginal microbiome, which can influence the local immune cell population, inflammation status, and HIV prevention drug levels. While a low-diversity composition dominated by Lactobacillus crispatus is associated with a decreased risk of HIV acquisition, high diversity environments associated with bacterial vaginosis increase risk of HIV. Given the important role of the vaginal microbiome in determining HIV susceptibility, altering the microbiome towards a Lactobacillus-dominated state is an attractive complementary strategy to reduce HIV incidence rates. Here, we provide an overview of the mechanisms by which the vaginal microbiome may contribute to HIV acquisition risk. Furthermore, we address the advantages and limitations of historical treatments and emerging technologies under investigation to modify the vaginal microbiome, including: antibiotics, bacteriophages, probiotics, topicals, and engineered bacteria. By addressing the current state of vaginal microbiome knowledge and strategies for manipulation, we hope to amplify the growing calls for increased resources and research into vaginal microbial health, which will be essential to accelerating preventative efforts amongst the world's most vulnerable populations.

Human immunodeficiency virus prevalence and high-risk behavior of home-based and nonhome-based female sex workers in three high-prevalent North-Eastern States of India

Background

Female sex workers (FSWs) have been identified as an important target group for human immunodeficiency virus (HIV)/sexually transmitted infections prevention.

Objectives

This study aimed to describe sociodemographic and sex work characteristics and to identify the risk factors for HIV infection with special focus on the variations between home-based (HB) and non-HB (NHB) FSWs in three high-prevalent North-Eastern states of India: Manipur, Mizoram, and Nagaland.

Methods

Data from the National Integrated Bio-Behavioural Surveillance (IBBS) conducted in India during 2014-2015 were utilized in the study. IBBS is a quantitative survey conducted among identified high risk sub within India. Logistic regression analyses were performed using SAS 9.3.2 to determine the distribution and associations of sociodemographics and risk behaviors with HIV seropositivity of HB and NHB FSWs.

Results

HIV prevalence was found higher among NHB FSWs compared to HB FSW (7.3% vs. 4.6%). The proportions of FSW among HB (66.7%) were in sex work for longer duration are significantly higher than for NHB (60.2%) while risk of HIV infection due to injecting drug use was higher in NHB FSW (11.7% vs. 8.7%). Reference to FSW who were currently married, those who were widowed/divorced/separated had 2.73-fold risk of HIV. FSW who did not have any other income source were associated with 1.73 times more risk of HIV infection. Injecting drugs user among FSW respondents had four times higher likelihood to be HIV positive.

Conclusion

A substantial proportion of NHB FSWs is mobile in nature. Targeted interventions are required urgently to minimize HIV risk among those FSWs especially the widowed/divorced/separated, sex work is only income source and who used injecting drugs for nonmedical purpose.

Individual and community-level factors associated with lifetime number of sexual partners among women aged 15-49 in Eswatini

INTRODUCTION

Understanding the risk factors for behavioral patterns in sexual relationships play a significant role in the reduction of the transmission of HIV/AIDS and other sexually transmitted infections.

OBJECTIVE

To investigate individual and community level factors on the lifetime number of sexual partners of women in Eswatini.

MATERIAL AND METHODS

The study was a secondary cross-sectional analysis of the 2014 Eswatini Multiple Indicator Cluster Survey (MICS). A total of 2,832 women aged 15-49 years were asked in total, how many different people have you had sexual intercourse in your lifetime. The multilevel negative binomial regression model was used to analyze the data.

RESULTS

The overall mean number of lifetime sexual partners was 2.78 (95% CI: 2.66, 2.91) in 2014. Compared to women aged 15-19, those aged 20 years and older, formerly married or never married reported more lifetime sexual partners compared to currently married women. Those that were aged 15 years and older at sexual debut reported fewer lifetime sexual partners compared to those that were aged less than 15 years. Compared to women that used a condom at last sexual intercourse, those that did not use a condom at last sexual encounter reported fewer lifetime sexual partners. Relative to women that lived with their sons and daughters, those that did not live with their sons and daughters reported more lifetime sexual partners. Women that lived in the Shiselweni and Lubombo regions reported fewer lifetime sexual partners compared to those residents in the Hhohho region.

CONCLUSION

Overall, lifetime sexual partners in Eswatini was significantly associated with individual characteristics and is unique across regions. Programs that aim to elucidate the factors associated with incident HIV infections among women in Eswatini should focus on individual and community-level factors that are associated with multiple sexual partnerships, which in turn might increase the risk of HIV exposure.

Viruses in the reproductive tract: On their way to the germ line?

Studies of vertebrate genomes have indicated that all species contain in their chromosomes stretches of DNA with sequence similarity to viral genomes. How such 'endogenous' viral elements (EVEs) ended up in host genomes is usually explained in general terms such as 'they entered the germ line at some point during evolution'. This seems a correct statement, but is also rather imprecise. The vast number of endogenous viral sequences suggest that common routes to the 'germ line' may exist, as relying on chance alone may not easily explain the abundance of EVEs in modern mammalian genomes. An increasing number of virus types have been detected in human semen and a growing number of studies have reported on viral infections that cause male infertility or subfertility and on viral infections that threaten in vitro fertilisation practices. Thus, it is timely to survey the pathway(s) that viruses can use to gain access to the human germ line. Embryo transfer and semen quality studies in livestock form another source of relevant information because virus infection during reproduction is clearly unwanted, as is the case for the human situation. In this review, studies on viruses in the male and female reproductive tract and in the early embryo will be discussed to propose a plausible viral route to the mammalian germ line.

Partner HIV Serostatus Impacts Viral Load, Genital HIV Shedding, and Immune Activation in HIV-Infected Individuals

Studies of seronegative individuals in HIV discordant relationships provide important insights into the effects of HIV exposure on the seronegative partner, but few have examined the impact of partner serostatus on disease progression in seropositive individuals. We investigated the impact of HIV serostatus on clinical and biological factors influencing HIV disease progression in 337 HIV-infected heterosexual individuals in stable long-term HIV-seroconcordant or HIV-serodiscordant relationships. Seroconcordant individuals had significantly higher plasma viral loads (pVLs) than HIV-infected partners in serodiscordant partnerships [4.4 log10 copies RNA/mL (interquartile range 3.7-5.0) versus 3.9 (3.3-4.5), P < 0.0001], irrespective of gender. pVLs correlated inversely with CD4 T-cell counts, although CD4 counts did not differ significantly between seroconcordant and serodiscordant individuals. HIV+ seroconcordant individuals had higher frequencies of CCR5 CD4 and CD8 T cells (P = 0.03 and P = 0.02, respectively) than HIV+ individuals in serodiscordant relationships and higher concentrations of plasma IL-1β (P = 0.04), TNF-α (P = 0.02), and IL-10 (P = 0.02). Activated CD4 T-cell frequencies and TNF-α were the most influential in determining variation in pVLs, independently of CD4 counts. In addition, HIV+ seroconcordant women had significantly higher genital VLs (gVLs) than HIV+ women in serodiscordant relationships (P < 0.001), with pVLs correlating significantly with gVLs (Rho = 0.65, P < 0.0001). Cervical and blood T-cell activation tended to correlate positively, although partner seroconcordance did not influence genital T-cell activation. We conclude that HIV+ seroconcordant individuals have higher frequencies of activated, CCR5-expressing T cells in blood and higher pVLs and gVLs than their HIV+ counterparts in discordant relationships, which could translate to faster disease progression or larger viral reservoir.

Current Status of Latency Reversing Agents Facing the Heterogeneity of HIV-1 Cellular and Tissue Reservoirs

One of the most explored therapeutic approaches aimed at eradicating HIV-1 reservoirs is the "shock and kill" strategy which is based on HIV-1 reactivation in latently-infected cells ("shock" phase) while maintaining antiretroviral therapy (ART) in order to prevent spreading of the infection by the neosynthesized virus. This kind of strategy allows for the "kill" phase, during which latently-infected cells die from viral cytopathic effects or from host cytolytic effector mechanisms following viral reactivation. Several latency reversing agents (LRAs) with distinct mechanistic classes have been characterized to reactivate HIV-1 viral gene expression. Some LRAs have been tested in terms of their potential to purge latent HIV-1 in vivo in clinical trials, showing that reversing HIV-1 latency is possible. However, LRAs alone have failed to reduce the size of the viral reservoirs. Together with the inability of the immune system to clear the LRA-activated reservoirs and the lack of specificity of these LRAs, the heterogeneity of the reservoirs largely contributes to the limited success of clinical trials using LRAs. Indeed, HIV-1 latency is established in numerous cell types that are characterized by distinct phenotypes and metabolic properties, and these are influenced by patient history. Hence, the silencing mechanisms of HIV-1 gene expression in these cellular and tissue reservoirs need to be better understood to rationally improve this cure strategy and hopefully reach clinical success.

Barriers of Mucosal Entry of HIV/SIV

Most new HIV infections, over 80%, occur through sexual transmission. During sexual transmission, the virus must bypass specific female and male reproductive tract anatomical barriers to encounter viable target cells. Understanding the generally efficient ability of these barrier to exclude HIV and the precise mechanisms of HIV translocation beyond these genital barriers is essential for vaccine and novel therapeutic development. In this review, we explore the mucosal, barriers of cervico-vaginal and penile tissues that comprise the female and male reproductive tracts. The unique cellular assemblies f the squamous and columnar epithelium are illustrate highlighting their structure and function. Each anatomical tissue offers a unique barrier to virus entry in healthy individuals. Unfortunately barrier dysfunction can lead to HIV transmission. How these diverse mucosal barriers have the potential to fail is considered, highlighting those anatomical areas that are postulated to offer a weaker barrier and are; therefore, more susceptible to viral ingress. Risk factors, such as sexually transmitted infections, microbiome dysbiosis, and high progestin environments are also associated with increased acquisition of HIV. How these states may affect the integrity of mucosal barriers leading to HIV acquisition are discussed suggesting mechanisms of transmission and revealing potential targets for intervention.

HIV and SIV in Body Fluids: From Breast Milk to the Genitourinary Tract

HIV-1 is present in many secretions including oral, intestinal, genital, and breast milk. However, most people exposed to HIV-1 within these mucosal compartments do not become infected despite often frequent and repetitive exposure over prolonged periods of time. In this review, we discuss what is known about the levels of cell-free HIV RNA, cell-associated HIV DNA and cell-associated HIV RNA in external secretions. Levels of virus are usually lower than contemporaneously obtained blood, increased in settings of inflammation and infection, and decreased in response to antiretroviral therapy. Additionally, each mucosal compartment has unique innate and adaptive immune responses that affect the composition and presence of HIV-1 within each external secretion. We discuss the current state of knowledge about the types and amounts of virus present in the various excretions, touch on innate and adaptive immune responses as they affect viral levels, and highlight important areas for further study.

Seminal Simian Immunodeficiency Virus in Chronically Infected Cynomolgus Macaques Is Dominated by Virus Originating from Multiple Genital Organs

The sexual transmission of viruses is responsible for the spread of multiple infectious diseases. Although the human immunodeficiency virus (HIV)/AIDS pandemic remains fueled by sexual contacts with infected semen, the origin of virus in semen is still unknown. In a substantial number of HIV-infected men, viral strains present in semen differ from the ones in blood, suggesting that HIV is locally produced within the genital tract. Such local production may be responsible for the persistence of HIV in semen despite effective antiretroviral therapy. In this study, we used single-genome amplification, amplicon sequencing (env gene), and phylogenetic analyses to compare the genetic structures of simian immunodeficiency virus (SIV) populations across all the male genital organs and blood in intravenously inoculated cynomolgus macaques in the chronic stage of infection. Examination of the virus populations present in the male genital tissues of the macaques revealed compartmentalized SIV populations in testis, epididymis, vas deferens, seminal vesicles, and urethra. We found genetic similarities between the viral strains present in semen and those in epididymis, vas deferens, and seminal vesicles. The contribution of male genital organs to virus shedding in semen varied among individuals and could not be predicted based on their infection or proinflammatory cytokine mRNA levels. These data indicate that rather than a single source, multiple genital organs are involved in the release of free virus and infected cells into semen. These findings have important implications for our understanding of systemic virus shedding and persistence in semen and for the design of eradication strategies to access viral reservoirs.

IMPORTANCE Semen is instrumental for the dissemination of viruses through sexual contacts. Worryingly, a number of systemic viruses, such as HIV, can persist in this body fluid in the absence of viremia. The local source(s) of virus in semen, however, remains unknown. To elucidate the anatomic origin(s) of the virus released in semen, we compared viral populations present in semen with those in the male genital organs and blood of the Asian macaque model, using single-genome amplification, amplicon sequencing (env gene), and phylogenetic analysis. Our results show that multiple genital tissues harbor compartmentalized strains, some of them (i.e., from epididymis, vas deferens, and seminal vesicles) displaying genetic similarities with the viral populations present in semen. This study is the first to uncover local genital sources of viral populations in semen, providing a new basis for innovative targeted strategies to prevent and eradicate HIV in the male genital tract.

Enhanced Sexually Transmitted Infection Screening for Mycoplasma genitalium in Human Immunodeficiency Virus -Infected US Air Force Personnel

Three-site genital and extragenital screening for Mycoplasma genitalium in 102 asymptomatic Air Force members with human immunodeficiency virus (HIV) infection revealed 19 (18.6%) cases of M. genitalium, commonly (58%) in rectal samples. Because M. genitalium is associated with both HIV acquisition and transmission, these findings suggest that it should be included in routine screening of HIV-infected individuals for sexually transmitted infections.

Genital-Systemic Chemokine Gradients and the Risk of HIV Acquisition in Women

Supplemental Digital Content is Available in the Text.

Background:

Mucosal and systemic immune mediators have been independently associated with HIV acquisition risk, but the relationship between compartments remains unclear.

Methods:

To address this, the concentrations of 12 cytokines were compared in matched plasma and cervicovaginal lavages (CVLs) from 57 HIV-positive women before their acquisition of HIV (cases) and 50 women who remained uninfected (controls) during the CAPRISA 004 trial.

Results:

Although genital IP-10 concentrations were significantly higher in cases, plasma IP-10 concentrations were inversely associated with HIV risk. Comparing differences in mucosal and systemic cytokine concentrations between cases and controls, mucosa-biased gradients indicating higher cervicovaginal lavage relative to plasma concentrations were observed for all 5 chemokines in the panel. Four were significantly associated with HIV acquisition, including IP-10 (odds ratio [OR] 1.73, 95% confidence interval [CI]: 1.27 to 2.36), macrophage inflammatory protein–1β (OR 1.72, 95% CI: 1.23 to 2.40), interleukin (IL)-8 (OR 1.50, 95% CI: 1.09 to 2.05), and monocyte chemotactic protein-1 (OR 1.36, 95% CI: 1.01 to 1.83). None of the other 7 cytokines tested predicted HIV risk. Decision tree analyses confirmed this association, with gradients of IP-10, IL-8, and granulocyte-macrophage colony-stimulating factor concentrations correctly classifying 77% of HIV outcomes.

Conclusions:

Our findings suggest that mucosa-biased gradients of IP-10, macrophage inflammatory protein–1β, IL-8, and monocyte chemotactic protein-1 are associated with an increased risk of HIV infection.

Long-term consequences of early sexual initiation on young adult health: A causal inference approach

Although early sexual initiation has been linked to negative outcomes, it is unknown whether these effects are causal. In this study, we use propensity score methods to estimate the causal effect of early sexual initiation on young adult sexual risk behaviors and health outcomes using data from the National Longitudinal Study of Adolescent to Adult Health. We found that early sexual initiation predicted having 2 or more partners (for both males and females) and having a sexually transmitted infection in the past year (females only) but did not predict depressive symptoms in the past week (for either gender). These results underscore the importance of continued programmatic efforts to delay age of sexual initiation, particularly for females.

Mechanisms of HIV persistence in HIV reservoirs

The establishment and maintenance of HIV reservoirs that lead to persistent viremia in patients on antiretroviral drugs remains the greatest challenge of the highly active antiretroviral therapy era. Cellular reservoirs include resting memory CD4+ T lymphocytes, implicated as the major HIV reservoir, having a half-life of approximately 44 months while this is less than 6 hours for HIV in plasma. In some individuals, persistent viremia consists of invariant HIV clones not detected in circulating resting CD4+ T lymphocytes suggesting other possible sources of residual viremia. Some anatomical reservoirs that may harbor such cells include the brain and the central nervous system, the gastrointestinal tract and the gut-associated lymphoid tissue and other lymphoid organs, and the genital tract. The presence of immune cells and other HIV susceptible cells, occurring in differing compositions in anatomical reservoirs, coupled with variable and poor drug penetration that results in suboptimal drug concentrations in some sites, are all likely factors that fuel the continued low-level replication and persistent viremia during treatment. Latently, HIV-infected CD4+ T cells harboring replication-competent virus, HIV cell-to-cell spread, and HIV-infected T cell homeostatic proliferation due to chronic immune activation represent further drivers of this persistent HIV viremia during highly active antiretroviral therapy.

Timing of First Sexual Intercourse and Young Adult Health Outcomes

PURPOSE

To examine how age of onset of sexual intercourse is associated with past-year and lifetime sexually transmitted infections (STIs) and depression in young adulthood.

METHODS

We examined how occurrence of a lifetime and past-year STI, lifetime diagnosis of depression, and past-week depressive symptoms differed as a function of age of onset of sexual intercourse using data from the National Longitudinal Study of Adolescent to Adult Health (Add Health; N = 8,938 individuals). Time-varying effect models were used to examine how age of onset, measured as continuous age, was associated with these outcomes in young adulthood, with all analyses stratified to examine gender differences.

RESULTS

Individuals who engaged in first intercourse before age 16 reported higher than average rates of all outcomes studied; for example, an estimated 35% of women and 12% of men who initiated at age 14 years reported a lifetime STI, compared with about 5% of those who initiated at age 24 years. Timing of first intercourse past the mid-twenties was associated with lower than average rates of STIs and lifetime depression diagnoses but was associated with a somewhat higher level of past-year depressive symptoms. Patterns were similar by gender, although there was little difference in men's depression diagnoses by age of onset.

CONCLUSIONS

Results suggest that sexual intercourse before age 16 years may be associated with higher rates of STIs and depression. Findings provide support for comprehensive programs that both promote delay of first intercourse and provide safe sex and psychological support for those who initiate early.

Progress and Perspectives on HIV-1 microbicide development

The majority of HIV-1 infections occur via sexual intercourse. Women are the most affected by the epidemic, particularly in developing countries, due to their socio-economic dependence on men and the fact that they are often victims of gender based sexual violence. Despite significant efforts that resulted in the reduction of infection rates in some countries, there is still need for effective prevention methods against the virus. One of these methods for preventing sexual transmission in women is the use of microbicides. In this review we provide a summary of the progress made toward the discovery of affordable and effective HIV-1 microbicides and suggest future directions. We show that there is a wide range of compounds that have been proposed as potential microbicides. Although most of them have so far failed to show protection in humans, there are many promising ones currently in pre-clinical studies and in clinical trials.

In Vitro Pre- and Post-Exposure Prophylaxis Using HIV Inhibitors as Microbicides Against Cell-Free or Cell-Associated HIV-1 Infection

Several classes of microbicides are being evaluated for the prevention of sexual HIV transmission. In vivo, the infectious dose and viral source involved in transmission remain uncertain and it is likely that women will use microbicides both before and after high-risk HIV exposure. Therefore, we evaluated HIV entry inhibitors (EIs) and reverse transcriptase inhibitors (RTIs) for their ability to block cell-free and cell-associated HIV-1 infection in co-cultures of monocyte-derived dendritic cells (MO-DC) and CD4+T-cells using settings of pre- and post-exposure prophylaxis. In the pre-exposure assay, where compound was present before, during and 24 h after infection, all tested EIs (BMS806, TAK779 and T20) and RTIs (PMPA, TMC120 and UC781) blocked infection with 10−4multiplicity of infection (MOI) of cell-free virus at a dose between 100 and 10,000 nM, dependent on the compound used. At 10−3MOI, however, only T20 and the RTIs completely blocked infection. Furthermore, in experiments with cell-associated virus, EIs were ineffective, whereas RTIs actively blocked infection with similar potency as in the experiments with cell-free virus. In the post-exposure assay, where compound was added 2 h after infection and remained present for 24 h, EIs were inactive whereas RTIs blocked cell-free and cell-associated viral infections equally efficiently. Moreover, post-exposure prophylaxis initiated 24 h after infection with cell-free or cell-associated HIV-1 was still effective with 1,000 nM of TMC120. Both EIs and RTIs were non-cytotoxic at any tested concentration for MO-DC and CD4+T-cells in co-culture. Our study shows that RTIs are potent inhibitors of cell-free and cell-associated virus used either in pre- or post-exposure settings. It highlights that parameters such as viral input, viral source, the time of compound addition and the target cells should be considered in microbicides evaluation.

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).

Chlamydia trachomatis Infection of Endocervical Epithelial Cells Enhances Early HIV Transmission Events

Chlamydia trachomatis causes a predominantly asymptomatic, but generally inflammatory, genital infection that is associated with an increased risk for HIV acquisition. Endocervical epithelial cells provide the major niche for this obligate intracellular bacterium in women, and the endocervix is also a tissue in which HIV transmission can occur. The mechanism by which CT infection enhances HIV susceptibility at this site, however, is not well understood. Utilizing the A2EN immortalized endocervical epithelial cell line grown on cell culture inserts, we evaluated the direct role that CT-infected epithelial cells play in facilitating HIV transmission events. We determined that CT infection significantly enhanced the apical-to-basolateral migration of cell-associated, but not cell-free, HIVBaL, a CCR5-tropic strain of virus, across the endocervical epithelial barrier. We also established that basolateral supernatants from CT-infected A2EN cells significantly enhanced HIV replication in peripheral mononuclear cells and a CCR5+ T cell line. These results suggest that CT infection of endocervical epithelial cells could facilitate both HIV crossing the mucosal barrier and subsequent infection or replication in underlying target cells. Our studies provide a mechanism by which this common STI could potentially promote the establishment of founder virus populations and the maintenance of local HIV reservoirs in the endocervix. Development of an HIV/STI co-infection model also provides a tool to further explore the role of other sexually transmitted infections in enhancing HIV acquisition.

Multiple imputation for non-response when estimating HIV prevalence using survey data

BACKGROUND

Missing data are a common feature in many areas of research especially those involving survey data in biological, health and social sciences research. Most of the analyses of the survey data are done taking a complete-case approach, that is taking a list-wise deletion of all cases with missing values assuming that missing values are missing completely at random (MCAR). Methods that are based on substituting the missing values with single values such as the last value carried forward, the mean and regression predictions (single imputations) are also used. These methods often result in potential bias in estimates, in loss of statistical information and in loss of distributional relationships between variables. In addition, the strong MCAR assumption is not tenable in most practical instances.

METHODS

Since missing data are a major problem in HIV research, the current research seeks to illustrate and highlight the strength of multiple imputation procedure, as a method of handling missing data, which comes from its ability to draw multiple values for the missing observations from plausible predictive distributions for them. This is particularly important in HIV research in sub-Saharan Africa where accurate collection of (complete) data is still a challenge. Furthermore the multiple imputation accounts for the uncertainty introduced by the very process of imputing values for the missing observations. In particular national and subgroup estimates of HIV prevalence in Zimbabwe were computed using multiply imputed data sets from the 2010-11 Zimbabwe Demographic and Health Surveys (2010-11 ZDHS) data. A survey logistic regression model for HIV prevalence and demographic and socio-economic variables was used as the substantive analysis model. The results for both the complete-case analysis and the multiple imputation analysis are presented and discussed.

RESULTS

Across different subgroups of the population, the crude estimates of HIV prevalence are generally not identical but their variations are consistent between the two approaches (complete-case analysis and multiple imputation analysis). The estimates of standard errors under the multiple imputation are predominantly smaller, hence leading to narrower confidence intervals, than under the complete case analysis. Under the logistic regression adjusted odds ratios vary greatly between the two approaches. The model based confidence intervals for the adjusted odds ratios are wider under the multiple imputation which is indicative of the inclusion of a combined measure of the within and between imputation variability.

CONCLUSIONS

There is considerable variation between estimates obtained between the two approaches. The use of multiple imputations allows the uncertainty brought about by the imputation process to be measured. This consequently yields more reliable estimates of the parameters of interest and reduce the chances of declaring significant effects unnecessarily (type I error). In addition, the utilization of the powerful and flexible statistical computing packages in R enhances the computations.

Sexual transmission of Lyme disease: challenging the tickborne disease paradigm

Lyme disease caused by the spirochete Borrelia burgdorferi has become a major worldwide epidemic. In this article, we explore the clinical, epidemiological and experimental evidence for sexual transmission of Lyme disease in animal models and humans. Although the likelihood of sexual transmission of the Lyme spirochete remains speculative, the possibility of Lyme disease transmission via intimate human contact merits further study.

Gene Expression Profiling of Human Vaginal Cells In Vitro Discriminates Compounds with Pro-Inflammatory and Mucosa-Altering Properties: Novel Biomarkers for Preclinical Testing of HIV Microbicide Candidates

BACKGROUND

Inflammation and immune activation of the cervicovaginal mucosa are considered factors that increase susceptibility to HIV infection. Therefore, it is essential to screen candidate anti-HIV microbicides for potential mucosal immunomodulatory/inflammatory effects prior to further clinical development. The goal of this study was to develop an in vitro method for preclinical evaluation of the inflammatory potential of new candidate microbicides using a microarray gene expression profiling strategy.

METHODS

To this end, we compared transcriptomes of human vaginal cells (Vk2/E6E7) treated with well-characterized pro-inflammatory (PIC) and non-inflammatory (NIC) compounds. PICs included compounds with different mechanisms of action. Gene expression was analyzed using Affymetrix U133 Plus 2 arrays. Data processing was performed using GeneSpring 11.5 (Agilent Technologies, Santa Clara, CA).

RESULTS

Microarraray comparative analysis allowed us to generate a panel of 20 genes that were consistently deregulated by PICs compared to NICs, thus distinguishing between these two groups. Functional analysis mapped 14 of these genes to immune and inflammatory responses. This was confirmed by the fact that PICs induced NFkB pathway activation in Vk2 cells. By testing microbicide candidates previously characterized in clinical trials we demonstrated that the selected PIC-associated genes properly identified compounds with mucosa-altering effects. The discriminatory power of these genes was further demonstrated after culturing vaginal cells with vaginal bacteria. Prevotella bivia, prevalent bacteria in the disturbed microbiota of bacterial vaginosis, induced strong upregulation of seven selected PIC-associated genes, while a commensal Lactobacillus gasseri associated to vaginal health did not cause any changes.

CONCLUSIONS

In vitro evaluation of the immunoinflammatory potential of microbicides using the PIC-associated genes defined in this study could help in the initial screening of candidates prior to entering clinical trials. Additional characterization of these genes can provide further insight into the cervicovaginal immunoinflammatory and mucosal-altering processes that facilitate or limit HIV transmission with implications for the design of prevention strategies.

Variability of human immunodeficiency virus-1 in the female genital reservoir during genital reactivation of herpes simplex virus type 2

Clinical and subclinical genital herpes simplex virus type 2 (HSV-2) reactivations have been associated with increases in human immunodeficiency virus (HIV)-1 genital shedding. Whether HSV-2 shedding contributes to the selection of specific genital HIV-1 variants remains unknown. We evaluated the genetic diversity of genital and blood HIV-1 RNA and DNA in 14 HIV-1/HSV-2-co-infected women, including seven with HSV-2 genital reactivation, and seven without as controls. HIV-1 DNA and HIV-1 RNA env V1-V3 sequences in paired blood and genital samples were compared. The HSV-2 selection pressure on HIV was estimated according to the number of synonymous substitutions (dS), the number of non-synonymous substitutions (dN) and the dS/dN ratio within HIV quasi-species. HIV-1 RNA levels in cervicovaginal secretions were higher in women with HSV-2 replication than in controls (p0.02). Plasma HIV-1 RNA and genital HIV-1 RNA and DNA were genetically compartmentalized. No differences in dS, dN and the dS/dN ratio were observed between the study groups for either genital HIV-1 RNA or plasma HIV-1 RNA. In contrast, dS and dN in genital HIV-1 DNA were significantly higher in patients with HSV-2 genital reactivation (p <0.01 and p <0.05, respectively). The mean of the dS/dN ratio in genital HIV-1 DNA was slightly higher in patients with HSV-2 genital replication, indicating a trend for purifying selection (p 0.056). HSV-2 increased the genetic diversity of genital HIV-1 DNA. These observations confirm molecular interactions between HSV-2 and HIV-1 at the genital tract level.

Herpes simplex virus type 2 (HSV-2) genital shedding in HSV-2-/HIV-1-co-infected women receiving effective combination antiretroviral therapy

The dynamics of genital shedding of HSV-2 DNA was assessed in HIV-1-infected women taking combination antiretroviral therapy (cART). HIV-1 RNA, HIV-1 DNA and HSV DNA loads were measured during 12-18 months using frozen plasma, PBMC and cervicovaginal lavage samples from 22 HIV-1-infected women, including 17 women naive for antiretroviral therapy initiating cART and 5 women with virological failure switching to a new regimen. Nineteen (86%) women were HSV-2-seropositive. Among HSV-2-/HIV-1-co-infected women, HIV-1 RNA loads showed a rapid fall from baseline after one month of cART, in parallel in paired plasma and cervicovaginal secretions. In contrast, HIV-1 DNA loads did not show significant variations from baseline up to 18 months of treatment in both systemic and genital compartments. HSV DNA was detected at least once in 12 (63%) of 19 women during follow up: HSV-2 shedding in the genital compartment was observed in 11% of cervicovaginal samples at baseline and in 16% after initiating or switching cART. Cervicovaginal HIV-1 RNA loads were strongly associated with plasma HIV-1 RNA loads over time, but not with cervicovaginal HSV DNA loads. Reactivation of genital HSV-2 replication frequently occurred despite effective cART in HSV-2-/HIV-1-co-infected women. Genital HSV-2 replication under cART does not influence cervicovaginal HIV-1 RNA or DNA shedding.

Anti-HIV-1 activity of flavonoid myricetin on HIV-1 infection in a dual-chamber in vitro model

HIV infection by sexual transmission remains an enormous global health concern. More than 1 million new infections among women occur annually. Microbicides represent a promising prevention strategy that women can easily control. Among emerging therapies, natural small molecules such as flavonoids are an important source of new active substances. In this study we report the in vitro cytotoxicity and anti-HIV-1 and microbicide activity of the following flavonoids: Myricetin, Quercetin and Pinocembrin. Cytotoxicity tests were conducted on TZM-bl, HeLa, PBMC, and H9 cell cultures using 0.01-100 µM concentrations. Myricetin presented the lowest toxic effect, with Quercetin and Pinocembrin relatively more toxic. The anti-HIV-1 activity was tested with TZM-bl cell plus HIV-1 BaL (R5 tropic), H9 and PBMC cells plus HIV-1 MN (X4 tropic), and the dual tropic (X4R5) HIV-1 89.6. All flavonoids showed anti-HIV activity, although Myricetin was more effective than Quercetin or Pinocembrin. In TZM-bl cells, Myricetin inhibited ≥90% of HIV-1 BaL infection. The results were confirmed by quantification of HIV-1 p24 antigen in supernatant from H9 and PBMC cells following flavonoid treatment. In H9 and PBMC cells infected by HIV-1 MN and HIV-1 89.6, Myricetin showed more than 80% anti-HIV activity. Quercetin and Pinocembrin presented modest anti-HIV activity in all experiments. Myricetin activity was tested against HIV-RT and inhibited the enzyme by 49%. Microbicide activities were evaluated using a dual-chamber female genital tract model. In the in vitro microbicide activity model, Myricetin showed promising results against different strains of HIV-1 while also showing insignificant cytotoxic effects. Further studies of Myricetin should be performed to identify its molecular targets in order to provide a solid biological foundation for translational research.

Mycoplasma genitalium is associated with increased genital HIV type 1 RNA in Zimbabwean women

BACKGROUND

Mycoplasma genitalium is a common sexually transmitted infection associated with human immunodeficiency virus (HIV) infection. Some studies suggest that M. genitalium may increase the risk of HIV acquisition. However, results have been inconsistent, and this association has never been examined longitudinally.

METHODS

Stored endocervical samples from a longitudinal cohort study of 131 Zimbabwean women in whom HIV-1 seroconversion recently occurred were tested for detection and quantity of M. genitalium using polymerase chain reaction analysis. The associations between M. genitalium and the detection and quantity of genital HIV type 1 (HIV-1) RNA, the detection and quantity of plasma HIV-1 RNA, and the CD4(+) T-cell count was analyzed using mixed-effects regression analysis.

RESULTS

M. genitalium was detected in 10.5% of stored specimens (44 of 420), and infection persisted for up to 300 days. M. genitalium was independently associated with detection of genital HIV-1 RNA (adjusted odds ratio, 2.67; 95% confidence interval, .99-7.20), after adjustment for plasma viral load, viral set point, CD4(+) T-cell count, herpes simplex virus type 2 detection, and gonorrhea. There was no evidence of an association between M. genitalium detection or quantity and either plasma HIV-1 RNA load or CD4(+) T-cell count.

CONCLUSIONS

The growing evidence for an association between M. genitalium and HIV genital shedding and the high prevalence and persistence of M. genitalium in this population suggest that further research into this association is important. Consideration of the cost-effectiveness of M. genitalium screening interventions may be warranted.

Impact of CMV therapy with valganciclovir on immune activation and the HIV viral load in semen and blood: an observational clinical study

BACKGROUND

The HIV RNA viral load (VL) in vaginal secretions and semen is an independent predictor of HIV transmission. Blood VL is associated with semen VL, and local mucosal factors, such as semen cytomegalovirus (CMV) reactivation, may play an important role.

METHODS

Twenty-one HIV-CMV-coinfected, antiretroviral-naive men received 900 mg of oral valganciclovir once daily for 2 weeks in an open-label study. Blood and semen were collected at baseline, after 2 weeks of valganciclovir, and 2 months after therapy completion. The primary end point was change in semen HIV levels at 2 weeks, and the secondary end points were change in semen HIV VL at 2 months and change in semen CMV levels.

RESULTS

The HIV VLs fell significantly at 2 weeks in semen (median 3.44-3.02 log10 copies/mL, P = 0.02) and blood (median 3.61-3.10 log10 copies/mL, P < 0.01) and returned to baseline after therapy completion (median 3.24 and 3.71 log10 copies/mL in semen and blood, respectively). Semen CMV levels also fell on treatment (median 2.13-1.62 log10 copies/mL, P < 0.01) and continued to fall after therapy completion (median 0.91 log10 copies/mL at week 8, P < 0.001 vs. baseline). The reduced semen CMV VL was associated with decreased semen T-cell activation and enhanced CMV-specific T-cell responses in blood; changes in the semen HIV VL were not associated with immune parameters.

CONCLUSIONS

Although valganciclovir therapy was associated with reduced HIV and semen CMV levels, these results suggest that the reduced HIV VL was a direct drug effect rather than a CMV antiviral effect or CMV-associated immune alterations.

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.

Is there an association between HIV-1 genital shedding and cervical intraepithelial neoplasia 2/3 among women on antiretroviral therapy?

OBJECTIVE

Given the high prevalence of cervical intraepithelial neoplasia (CIN) grade 2/3 among HIV-infected women, we sought to examine the relationship between CIN 2/3 and HIV-1 genital shedding among women on highly active antiretroviral therapy (HAART).

MATERIALS AND METHODS

Paired plasma and cervical wick specimens for HIV-1 RNA measurements were obtained from 44 HIV-infected women with biopsy-confirmed CIN 2/3 (cases) and 44 age-matched HIV-infected women with normal cervical findings on colposcopy (controls). All subjects tested negative for sexually transmitted infections and had been stable on HAART for at least 3 months. HIV-1 viral load was measured in both blood and cervical specimens using commercial real-time polymerase chain reaction assays.

RESULTS

Cervical intraepithelial neoplasia 2/3 was not significantly associated with the detection or magnitude of plasma or cervical HIV-1 RNA shedding. HIV was detected in the plasma in 10 cases (23%) and 10 controls (25%) (odds ratio = 1.0; 95% confidence interval = 0.33-3.1). Cervical HIV-1 was detected in 6 cases (13.6%) and 9 controls (20.4%) (odds ratio = 0.61; 95% confidence interval = 0.20-1.90). Mean HIV-1 concentration in cervical secretions among women with CIN 2/3 who shed was 2.93 log10 copies versus 2.72 among controls (p = .65).

CONCLUSIONS

Among women on HAART, we found no relationship between CIN 2/3 and HIV-1 genital shedding.

HIV-1 subtype C is not associated with higher risk of heterosexual HIV-1 transmission: a multinational study among HIV-1 serodiscordant couples

BACKGROUND

HIV-1 subtype C has emerged as the most prevalent strain of HIV-1 worldwide, leading to speculation that subtype C may be more transmissible than other subtypes. We compared the risk of HIV-1 transmission for subtype C versus non-C subtypes (A, D, G and recombinant forms) among heterosexual African HIV-1 serodiscordant couples.

METHODS

We conducted a nested case-control analysis using data from two prospective cohort studies of heterosexual HIV-1 serodiscordant couples from six countries in eastern and southern Africa. Cases (N = 121) included incident HIV-1 transmissions that were established as linked within the serodiscordant partnership by viral sequencing; controls (N = 501) were nontransmitting HIV-1-infected partners. Subtype was determined for partial env and gag genes. Multiple logistic regression controlled for age and gender of the HIV-1-nfected partner and self-reported unprotected sex. Plasma and genital HIV-1 RNA concentrations were compared between subtype C and non-C subtypes using generalized estimating equations.

RESULTS

HIV-1 subtype C was not associated with increased risk of HIV-1 transmission compared with non-C subtypes: env adjusted odds ratio (adjOR) 1.14 [95% confidence interval (CI) 0.74-1.75, P = 0.6] and gag adjOR 0.98 (95% CI 0.63-1.52, P = 0.9). Plasma and genital HIV-1 RNA levels did not differ significantly for subtype C versus non-C.

CONCLUSION

In a geographically diverse population of heterosexual African HIV-1 serodiscordant couples, subtype C was not associated with greater risk of HIV-1 transmission compared with non-C subtypes, arguing against the hypothesis that subtype C is more transmissible compared with other common subtypes.

Initiation of antiretroviral therapy

With the widespread availability of antiretroviral therapy, there is a dramatic decline in HIV related morbidity and mortality in both developed and developing countries. Further, the current antiretroviral drug combinations are safer and the availability of newer monitoring assays and guidelines has vastly improved the patient management. The clinician needs to evaluate several key issues prior to institution of antiretroviral regimen including the correct stage of starting the treatment and the kind of regimen to initiate. In addition to various disease related factors, it is also critical to assess the patient's general condition including nutritional status, presence of co-morbidities and mental preparedness prior to starting the therapy. The patients need to develop an overall understanding of the treatment and its benefits and the importance of lifelong adherence to the drugs. The presence of special situations like pediatric age, older patients, pregnancy, lactation and presence of opportunistic infections also require modification of the therapy. This review briefly summarizes issues relevant to the clinician prior to the initiation of antiretroviral therapy.

Phenotype and functionality of CD4+ and CD8+ T cells in the upper reproductive tract of healthy premenopausal women

PROBLEM

The goal of this study was to investigate the phenotype and functional responsiveness of CD4(+) and CD8(+) T-cells in the upper reproductive tract of healthy premenopausal women. The lower reproductive tract is frequently studied as a site of sexually transmitted infections; however, the upper reproductive tract may also be a portal of entry and dissemination for pathogens, including HIV-1.

METHOD OF STUDY

Endometrial biopsy, endocervical curettage, cytobrush, and blood were collected during mid-luteal phase from 23 healthy women. T-cells were isolated and analyzed by flow cytometry.

RESULTS

As compared with their counterparts in blood, endometrial and endocervical T-cells had enhanced CCR5 expression, and were enriched for activated, effector memory cells. Endometrial T-cells were more responsive to polyclonal stimuli, producing a broad range of cytokines and chemokines.

CONCLUSION

These findings underscore the responsiveness of endometrial T-cells to stimulation, and reveal their activated phenotype. These findings also suggest susceptibility of the upper reproductive tract to HIV-1 infection.

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.

Modelling the impact of chlamydia screening on the transmission of HIV among men who have sex with men

BACKGROUND

Recent studies have found high prevalences of asymptomatic rectal chlamydia among HIV-infected men who have sex with men (MSM). Chlamydia could increase the infectivity of HIV and the susceptibility to HIV infection. We investigate the role of chlamydia in the spread of HIV among MSM and the possible impact of routine chlamydia screening among HIV-infected MSM at HIV treatment centres on the incidence of chlamydia and HIV in the overall MSM population.

METHODS

A mathematical model was developed to describe the transmission of HIV and chlamydia among MSM. Parameters relating to sexual behaviour were estimated from data from the Amsterdam Cohort Study among MSM. Uncertainty analysis was carried out for model parameters without confident estimates. The effects of different screening strategies for chlamydia were investigated.

RESULTS

Among all new HIV infections in MSM, 15% can be attributed to chlamydia infection. Introduction of routine chlamydia screening every six months among HIV-infected MSM during regular HIV consultations can reduce the incidence of both infections among MSM: after 10 years, the relative percentage reduction in chlamydia incidence would be 15% and in HIV incidence 4%, compared to the current situation. Chlamydia screening is more effective in reducing HIV incidence with more frequent screening and with higher participation of the most risky MSM in the screening program.

CONCLUSIONS

Chlamydia infection could contribute to the transmission of HIV among MSM. Preventive measures reducing chlamydia prevalence, such as routine chlamydia screening of HIV-infected MSM, can result in a decline in the incidence of chlamydia and HIV.

Sexually transmitted infections screening at HIV treatment centers for MSM can be cost-effective

OBJECTIVE

To estimate the cost-effectiveness of anorectal chlamydia screening among men who have sex with men (MSM) in care at HIV treatment centers.

DESIGN

Transmission model combined with economic analysis over a 20-year period.

SETTING AND PARTICIPANTS

MSM in care at HIV treatment centers.

INTERVENTION

Once-yearly or twice-yearly screening for anorectal chlamydia among MSM in care at HIV treatment centers.

MAIN OUTCOME MEASURES

Averted HIV and chlamydia infections; discounted quality-adjusted life-years and costs; incremental cost-effectiveness ratio (ICER).

RESULTS

Costs will be saved by routine chlamydia screening of MSM in care at HIV treatment centers if these patients seek little or no screening elsewhere. Nonroutine screening is considerably more expensive than routine screening offered within a scheduled visit. Adding once-yearly chlamydia screening for MSM in care at HIV treatment centers is cost saving when 30% or fewer of those men seek once-yearly screening elsewhere (1.5 to 8.1 million euro saved). Twice-yearly routine screening at HIV treatment centers is cost-effective only when routine screening takes place without additional nonroutine screening (1.9 million euro saved).

CONCLUSIONS

Adding annual chlamydia screening to the HIV consultation will be cost saving as long as only a limited proportion of men are nonroutinely screened. The ICER was most sensitive to the percentage of MSM that continue to be screened elsewhere.

Defining the interaction of HIV-1 with the mucosal barriers of the female reproductive tract

Worldwide, HIV-1 infects millions of people annually, the majority of whom are women. To establish infection in the female reproductive tract (FRT), HIV-1 in male ejaculate must overcome numerous innate and adaptive immune factors, traverse the genital epithelium, and establish infection in underlying CD4(+) target cells. How the virus achieves this remains poorly defined. By utilizing a new technique, we define how HIV-1 interacts with different tissues of the FRT using human cervical explants and in vivo exposure in the rhesus macaque vaginal transmission model. Despite previous claims of the squamous epithelium being an efficient barrier to virus entry, we reveal that HIV-1 can penetrate both intact columnar and squamous epithelial barriers to depths where the virus can encounter potential target cells. In the squamous epithelium, we identify virus entry occurring through diffusive percolation, penetrating areas where cell junctions are absent. In the columnar epithelium, we illustrate that virus does not transverse barriers as well as previously thought due to mucus impediment. We also show a statistically significant correlation between the viral load of inocula and the ability of HIV-1 to pervade the squamous barrier. Overall, our results suggest a diffusive percolation mechanism for the initial events of HIV-1 entry. With these data, we also mathematically extrapolate the number of HIV-1 particles that penetrate the mucosa per coital act, providing a biological description of the mechanism for HIV-1 transmission during the acute and chronic stages of infection.

Changes in HIV-1 subtypes B and C genital tract RNA in women and men after initiation of antiretroviral therapy

BACKGROUND

Combination antiretroviral therapy (cART) reduces genital tract human immunodeficiency virus type 1 (HIV-1) load and reduces the risk of sexual transmission, but little is known about the efficacy of cART for decreasing genital tract viral load (GTVL) and differences in sex or HIV-1 subtype.

METHODS

HIV-1 RNA from blood plasma, seminal plasma, or cervical wicks was quantified at baseline and at weeks 48 and 96 after entry in a randomized clinical trial of 3 cART regimens.

RESULTS

One hundred fifty-eight men and 170 women from 7 countries were studied (men: 55% subtype B and 45% subtype C; women: 24% subtype B and 76% subtype C). Despite similar baseline CD4(+) cell counts and blood plasma viral loads, women with subtype C had the highest GTVL (median, 5.1 log10 copies/mL) compared to women with subtype B and men with subtype C or B (4.0, 4.0, and 3.8 log10 copies/mL, respectively; P < .001). The proportion of participants with a GTVL below the lower limit of quantification (LLQ) at week 48 (90%) and week 96 (90%) was increased compared to baseline (16%; P < .001 at both times). Women were significantly less likely to have GTVL below the LLQ compared to men (84% vs 94% at week 48, P = .006; 84% vs 97% at week 96, P = .002), despite a more sensitive assay for seminal plasma than for cervical wicks. No difference in GTVL response across the 3 cART regimens was detected.

CONCLUSIONS

The female genital tract may serve as a reservoir of persistent HIV-1 replication during cART and affect the use of cART to prevent sexual and perinatal transmission of HIV-1.

Missed connections: HIV-infected people never in care

OBJECTIVE

Clinical interventions that lengthen life after HIV infection and significantly reduce transmission could have greater impact if more HIV-diagnosed people received HIV care. We tested a surveillance-based approach to investigating reasons for delayed entry to care.

METHODS

Health department staff in three states and two cities contacted eligible adults diagnosed with HIV four to 24 months previously who had no reported CD4+ lymphocyte (CD4) or viral load (VL) tests. The staff conducted interviews, performed CD4 and VL testing, and provided referrals to HIV medical care. Reported CD4 and VL tests were prospectively monitored to determine if respondents had entered care after the interview.

RESULTS

Surveillance-based follow-up uncovered problems with reporting CD4 and VL tests, resulting in surveillance improvements. However, reporting problems led to misspent effort locating people who were already in care. Follow-up proved difficult because contact information in surveillance case records was often outdated or incorrect. Of those reached, 37% were in care and 29% refused participation. Information from 132 people interviewed generated ideas for service improvements, such as emphasizing the benefits of early initiation of HIV care, providing coverage eligibility information soon after diagnosis, and leveraging other medical appointments to provide assistance with linkage to HIV care.

CONCLUSIONS

Surveillance-based follow-up of HIV-diagnosed individuals not linked to care provided information to improve both surveillance and linkage services, but was inefficient because of difficulties identifying, locating, and recruiting eligible people. Inefficiencies attributable to missing, incomplete, or inaccurate surveillance records are likely to diminish as data quality is improved through ongoing use.

Human cervicovaginal mucus contains an activity that hinders HIV-1 movement

Cervical and vaginal epithelia are primary barriers against HIV type I (HIV-1) entry during male-to-female transmission. Cervical mucus (CM) is produced by the endocervix and forms a layer locally as well as in the vaginal compartment in the form of cervicovaginal mucus (CVM). To study the potential barrier function of each mucus type during HIV-1 transmission, we quantified HIV-1 mobility in CM and CVM ex vivo using fluorescent microscopy. Virions and 200-nm PEGylated beads were digitally tracked and mean-squared displacement was calculated. The mobility of beads increased significantly in CVM compared with CM, consistent with the known decreased mucin concentration of CVM. Unexpectedly, HIV-1 diffusion was significantly hindered in the same CVM samples in which bead diffusion was unhindered. Inhibition of virus transport was envelope-independent. Our results reveal a previously unknown activity in CVM that is capable of impeding HIV-1 mobility to enhance mucosal barrier function.

Hormonal contraceptive use and female-to-male HIV transmission: a systematic review of the epidemiologic evidence

OBJECTIVE

To systematically review epidemiologic evidence assessing whether hormonal contraception alters the risk of HIV transmission from an HIV-positive woman to an HIV-negative male partner.

DESIGN

Systematic review.

METHODS

We included articles published or in press through December 15, 2011. We assessed studies with direct evidence on hormonal contraception use and HIV transmission, and summarized studies with indirect evidence related to genital or plasma viral load.

RESULTS

: One study provided direct evidence on oral contraceptive pills (OCPs) or injectable contraception and female-to-male HIV transmission; both injectables [Cox-adjusted hazard ratio (adjHR) 1.95, 95% confidence interval (CI) 1.06-3.58; marginal structural model (MSM) adjusted odds ratio (adjOR) 3.01, 95% CI 1.47-6.16] and OCPs (Cox adjHR 2.09, 95% CI 0.75-5.84; MSM adjOR 2.35, 95% CI 0.79-6.95) generated elevated point estimates, but only estimates for injectables were significant. Findings from 11 indirect studies assessing various hormonal contraception methods and viral genital shedding or setpoint were mixed, and seven of eight studies indicated no adverse effect of various hormonal contraception methods on plasma viral load.

CONCLUSION

The only direct study on OCPs or injectable contraception and female-to-male HIV transmission suggests increased risk with the use of injectables. Given the potential for confounding in observational data, the paucity of direct evidence on this subject, and mixed indirect evidence, additional evidence is needed.

From the laboratory to clinical trials and back again: lessons learned from HIV prevention trials

PROBLEM

Inadequate, irrelevant, or inappropriate timing of biological specimen collection during clinical trials is a cause for delay in understanding and explaining correlates of protection and/or effectiveness, particularly at the portal of entry in the context of sexual HIV transmission and its prevention.

METHODS

We present examples of HIV prevention trials to illustrate the impact of preplanned versus unplanned laboratory science program on the interpretation of trial results and advancement of the field.

RESULTS

Of the five completed pre-exposure prophylaxis trials, only two announced main outcome results simultaneously with data on correlates of drug-related effectiveness. In four of the vaccine trials completed, the only one that showed a protective effect presented data on protection correlates significantly later.

CONCLUSION

Clinical trials must preplan collaborative immunophysiological research and prioritize biological specimen collection and storage for enhancement of research on correlates of protection. Similarly appropriate specimens should be prioritized for pathogenesis research.

Dendritic cells and vaccine design for sexually-transmitted diseases

Dendritic cells (DCs) are major antigen presenting cells (APCs) that can initiate and control host immune responses toward either immunity or tolerance. These features of DCs, as immune orchestrators, are well characterized by their tissue localizations as well as by their subset-dependent functional specialties and plasticity. Thus, the level of protective immunity to invading microbial pathogens can be dependent on the subsets of DCs taking up microbial antigens and their functional plasticity in response to microbial products, host cellular components and the cytokine milieu in the microenvironment. Vaccines are the most efficient and cost-effective preventive medicine against infectious diseases. However, major challenges still remain for the diseases caused by sexually-transmitted pathogens, including HIV, HPV, HSV and Chlamydia. We surmise that the establishment of protective immunity in the female genital mucosa, the major entry and transfer site of these pathogens, will bring significant benefit for the protection against sexually-transmitted diseases. Recent progresses made in DC biology suggest that vaccines designed to target proper DC subsets may permit us to establish protective immunity in the female genital mucosa against sexually-transmitted pathogens.