Negative mucosal synergy between Herpes simplex type 2 and HIV in the female genital tract

A Reappraisal of the Antiviral Properties of and Immune Regulation through Dietary Phytochemicals

In the present era of the COVID-19 pandemic, viral infections remain a major cause of morbidity and mortality worldwide. In this day and age, viral infections are rampant and spreading rapidly. Among the most aggressive viral infections are ebola, AIDS (acquired immunodeficiency syndrome), influenza, and SARS (severe acute respiratory syndrome). Even though there are few treatment options for viral diseases, most of the antiviral therapies are ineffective owing to frequent mutations, the development of more aggressive strains, drug resistance, and possible side effects. Traditionally, herbal remedies have been used by healers, including for dietary and medicinal purposes. Many clinical and scientific studies have demonstrated the therapeutic potential of plant-derived natural compounds. Because of unsafe practices like blood transfusions and organ transplants from infected patients, medical supply contamination. Our antiviral therapies cannot achieve sterile immunity, and we have yet to find a cure for these pernicious infections. Herbs have been shown to improve therapeutic efficacy against a wide variety of viral diseases because of their high concentration of immunomodulatory phytochemicals (both immunoinhibitory and anti-inflammatory). Combined with biotechnology, this folk medicine system can lead to the development of novel antiviral drugs and therapies. In this Review, we will summarize some selected bioactive compounds with probable mechanisms of their antiviral actions, focusing on the immunological axis of these compounds.

Low-Level Anorectal HIV Shedding despite Effective Antiretroviral Therapy Is Not Driven by Mucosal Inflammation

Although antiretroviral treatment (ART) suppresses HIV RNA in blood and prevents transmission, low-level anorectal HIV RNA shedding persists in some ART-treated men who have sex with men. We collected anorectal biopsies and swabs from 55 men who have sex with men on effective ART, hypothesizing that anorectal shedding would be linked to microbiota-driven mucosal T cell activation. Lymphocytes were assessed by flow cytometry, soluble immune factors by multiplex immunoassay, neutrophils and epithelial integrity by immunofluorescence microscopy, and the anorectal microbiome by quantitative PCR and 16S rRNA gene sequencing. Unexpectedly, we found no evidence that anorectal HIV shedding was associated with the parameters of mucosal inflammation, including T cell activation, inflammatory cytokines, the density of neutrophils, or epithelial integrity. Moreover, the anorectal bacterial load was actually lower in the shedding group, with no major differences in bacterial composition. Instead, the strongest mucosal immune correlates of HIV shedding were an increase in central memory cell frequency and Ki67 expression as well as higher concentrations of the cytokine IL-7 in anorectal secretions. Anorectal HIV RNA shedding during effective ART was not driven by local inflammation; the associations seen with local homeostatic T cell proliferation will require further confirmation.

Viral Venereal Diseases of the Skin

Viral venereal diseases remain difficult to treat. Human papilloma virus (HPV) and herpes simplex virus (HSV) are two common viral venereal diseases. HPV infections are characterized by anogenital warts and less commonly by premalignant or malignant lesions. HSV infections classically present as grouped vesicles on an erythematous base with associated burning or pain; however, immunosuppressed patients may have atypical presentations with nodular or ulcerative lesions. This review discusses the epidemiology, diagnosis, and management of anogenital HPV and HSV infections with an emphasis on treatment modalities for the practicing dermatologist. Diagnosis of these diseases typically relies on clinical assessment, although multiple diagnostic techniques can be utilized and are recommended when diagnosis is uncertain or evaluating an individual with increased risk of malignancy. Management of HPV and HSV infections involves appropriate counseling, screening, and multiple treatment techniques. Particularly for HPV infections, a practitioner may need to use a combination of techniques to achieve the desired outcome.

Epidemiological Impact of Novel Preventive and Therapeutic HSV-2 Vaccination in the United States: Mathematical Modeling Analyses

This study aims to inform herpes simplex virus type 2 (HSV-2) vaccine development, licensure, and implementation by delineating the population-level impact of vaccination. Mathematical models were constructed to describe the transmission dynamics in presence of prophylactic or therapeutic vaccines assuming 50% efficacy, with application to the United States. Catch-up prophylactic vaccination will reduce, by 2050, annual number of new infections by 58%, incidence rate by 60%, seroprevalence by 21%, and avert yearly as much as 350,000 infections. Number of vaccinations needed to avert one infection was only 50 by 2050, 34 by prioritizing those aged 15-19 years, 4 by prioritizing the highest sexual risk group, 43 by prioritizing women, and 47 by prioritizing men. Therapeutic vaccination of infected adults with symptomatic disease will reduce, by 2050, annual number of new infections by 12%, incidence rate by 13%, seroprevalence by 4%, and avert yearly as much as 76,000 infections. Number of vaccinations needed to avert one infection was eight by 2050, two by prioritizing those aged 15-19 years, three by prioritizing the highest sexual risk group, seven by prioritizing men, and ten by prioritizing women. HSV-2 vaccination offers an impactful and cost-effective intervention to prevent genital herpes medical and psychosexual disease burden.

Identifying and managing infectious disease syndemics in patients with HIV

PURPOSE OF REVIEW

We will present recent articles focusing on HIV synergistic interactions with other sexually transmitted infections, tuberculosis, and hepatitis, as well as recent advances in the study of social and behavioral determinants that facilitate this clustering of infectious disease. For each synergistic interaction, we highlight evidence-based interventions that clinicians and policymakers should consider to tackle HIV and infectious disease syndemics.

RECENT FINDINGS

Significant advances in understanding the behavioral and structural determinants of HIV and other infectious disease synergisms have been made in the past years. Intervention strategies based on these new models have also been developed. It is now well understood that treating infectious disease syndemics will require a multidisciplinary and multipronged approach.

SUMMARY

HIV is synergistic with multiple other infectious diseases because the risk behaviors that lead to HIV acquisition may be similar to the other infections. The influence of HIV on the other infection may be due to immunosuppression associated with disease progression resulting in increased susceptibility (e.g., HIV and tuberculosis), especially when patients are not virologically suppressed using antiretroviral therapy. In reverse, another infectious disease may, when not treated, influence HIV disease progression. Social/structural determinants like homelessness, mass incarceration, and structural discrimination precipitate psychiatric comorbidity, substance use, and risky sex behavior which lead to the spread and co-occurrence of infectious disease.

Mechanisms of Endogenous HIV-1 Reactivation by Endocervical Epithelial Cells

Pharmacological HIV-1 reactivation to reverse latent infection has been extensively studied. However, HIV-1 reactivation also occurs naturally, as evidenced by occasional low-level viremia ("viral blips") during antiretroviral treatment (ART). Clarifying where blips originate from and how they happen could provide clues to stimulate latency reversal more effectively and safely or to prevent viral rebound following ART cessation. We studied HIV-1 reactivation in the female genital tract, a dynamic anatomical target for HIV-1 infection throughout all disease stages. We found that primary endocervical epithelial cells from several women reactivated HIV-1 from latently infected T cells. The endocervical cells' HIV-1 reactivation capacity further increased upon Toll-like receptor 3 stimulation with poly(I·C) double-stranded RNA or infection with herpes simplex virus 2 (HSV-2). Notably, acyclovir did not eliminate HSV-2-induced HIV-1 reactivation. While endocervical epithelial cells secreted large amounts of several cytokines and chemokines, especially tumor necrosis factor alpha (TNF-α), CCL3, CCL4, and CCL20, their HIV-1 reactivation capacity was almost completely blocked by TNF-α neutralization alone. Thus, immunosurveillance activities by columnar epithelial cells in the endocervix can cause endogenous HIV-1 reactivation, which may contribute to viral blips during ART or rebound following ART interruption.IMPORTANCE A reason that there is no universal cure for HIV-1 is that the virus can hide in the genome of infected cells in the form of latent proviral DNA. This hidden provirus is protected from antiviral drugs until it eventually reactivates to produce new virions. It is not well understood where in the body or how this reactivation occurs. We studied HIV-1 reactivation in the female genital tract, which is often the portal of HIV-1 entry and which remains a site of infection throughout the disease. We found that the columnar epithelial cells lining the endocervix, the lower part of the uterus, are particularly effective in reactivating HIV-1 from infected T cells. This activity was enhanced by certain microbial stimuli, including herpes simplex virus 2, and blocked by antibodies against the inflammatory cytokine TNF-α. Avoiding HIV-1 reactivation could be important for maintaining a functional HIV-1 cure when antiviral therapy is stopped.

HSV-2 Cellular Programming Enables Productive HIV Infection in Dendritic Cells

Genital herpes is a common sexually transmitted infection caused by herpes simplex virus type 2 (HSV-2). Genital herpes significantly enhances the acquisition and transmission of HIV-1 by creating a microenvironment that supports HIV infection in the host. Dendritic cells (DCs) represent one of the first innate cell types that encounter HIV-1 and HSV-2 in the genital mucosa. HSV-2 infection has been shown to modulate DCs, rendering them more receptive to HIV infection. Here, we investigated the potential mechanisms underlying HSV-2-mediated augmentation of HIV-1 infection. We demonstrated that the presence of HSV-2 enhanced productive HIV-1 infection of DCs and boosted inflammatory and antiviral responses. The HSV-2 augmented HIV-1 infection required intact HSV-2 DNA, but not active HSV-2 DNA replication. Furthermore, the augmented HIV infection of DCs involved the cGAS-STING pathway. Interestingly, we could not see any involvement of TLR2 or TLR3 nor suppression of infection by IFN-β production. The conditioning by HSV-2 in dual exposed DCs decreased protein expression of IFI16, cGAS, STING, and TBK1, which is associated with signaling through the STING pathway. Dual exposure to HSV-2 and HIV-1 gave decreased levels of several HIV-1 restriction factors, especially SAMHD1, TREX1, and APOBEC3G. Activation of the STING pathway in DCs by exposure to both HSV-2 and HIV-1 most likely led to the proteolytic degradation of the HIV-1 restriction factors SAMHD1, TREX1, and APOBEC3G, which should release their normal restriction of HIV infection in DCs. This released their normal restriction of HIV infection in DCs. We showed that HSV-2 reprogramming of cellular signaling pathways and protein expression levels in the DCs provided a setting where HIV-1 can establish a higher productive infection in the DCs. In conclusion, HSV-2 reprogramming opens up DCs for HIV-1 infection and creates a microenvironment favoring HIV-1 transmission.

Intranasal nanoemulsion-adjuvanted HSV-2 subunit vaccine is effective as a prophylactic and therapeutic vaccine using the guinea pig model of genital herpes

Genital herpes is a sexually transmitted disease representing a major global health concern. Currently, there is no approved vaccine and existing antiviral therapies exhibit limited efficacy. Herein, we describe an intranasal (IN) vaccine comprised of HSV-2 surface glycoproteins gD2 and gB2 formulated in a nanoemulsion adjuvant (NE01-gD2/gB2). Using the HSV-2 genital herpes guinea pig model, we demonstrate that IN NE01-gD2/gB2 induces higher levels of neutralizing antibody compared to a monovalent IN NE01-gD2 vaccine, but less than an intramuscular (IM) Alum/MPL-gD2 vaccine. Following intravaginal (IVag) challenge with HSV-2, the group immunized with IN NE01-gD2/gB2 exhibited significantly reduced acute and recurrent disease scores compared to placebo recipients. Significantly, latent virus was only detected in the dorsal root ganglia of 1 of 12 IN NE01-gD2/gB2-vaccinated animals compared to 11 of 12 placebo recipient. In the therapeutic model, IN NE01-gD2/gB2 immunized guinea pigs exhibited a significant reduction in the recurrent lesions scores (64%, p < 0.01), number of animal days with disease (64%, p < 0.01), number of animals with viral shedding (50%, p < 0.04) and reduction in virus positive vaginal swabs (56%, p < 0.04), These data suggests that the treatment may be effective in treating chronic disease and minimizing virus transmission. These results warrant advancing the development of IN NE01-gD2/gB2 as both a prophylactic and therapeutic vaccine against HSV-2.

A pro-inflammatory CD8+ T-cell subset patrols the cervicovaginal tract

The immune system of the cervicovaginal tract (CVT) must balance immunosurveillance and active immunity against pathogens with maintenance of tolerance to resident microbiota and to fetal and partner antigens for reproductive purposes. Thus, we predicted that CVT immunity is characterized by distinctive features compared to blood and other tissue compartments. Indeed, we found that CVT CD8+ T-cells had unique transcriptional profiles, particularly in their cytokine signature, compared to that reported for CD8+ T-cells in other tissue sites. Among these CVT CD8+ T-cells, we identified a CD69- CD103- subset that was characterized by reduced migration in response to tissue-exit signals and higher pro-inflammatory potential as compared to their blood counterpart. These inflammatory mucosal CD8+ T-cells (Tim) were increased in frequency in the CVT of individuals with chronic infection, pointing to a potential role in perpetuating inflammation. Our findings highlight the specialized nature of immunity within the CVT and identify Tim cells as potential therapeutic targets to tame tissue inflammation upon chronic infection.

Microbiota and Its Role on Viral Evasion: Is It With Us or Against Us?

Viruses are obligate intracellular pathogens that require the protein synthesis machinery of the host cells to replicate. These microorganisms have evolved mechanisms to avoid detection from the host immune innate and adaptive response, which are known as viral evasion mechanisms. Viruses enter the host through skin and mucosal surfaces that happen to be colonized by communities of thousands of microorganisms collectively known as the commensal microbiota, where bacteria have a role in the modulation of the immune system and maintaining homeostasis. These bacteria are necessary for the development of the immune system and to prevent the adhesion and colonization of bacterial pathogens and parasites. However, the interactions between the commensal microbiota and viruses are not clear. The microbiota could confer protection against viral infection by priming the immune response to avoid infection, with some bacterial species being required to increase the antiviral response. On the other hand, it could also help to promote viral evasion of certain viruses by direct and indirect mechanisms, with the presence of the microbiota increasing infection and viruses using LPS and surface polysaccharides from bacteria to trigger immunosuppressive pathways. In this work, we reviewed the interaction between the microbiota and viruses to prevent their entry into host cells or to help them to evade the host antiviral immunity. This review is focused on the influence of the commensal microbiota in the viruses' success or failure of the host cells infection.

Herpes Simplex Virus Evasion of Early Host Antiviral Responses

Herpes simplex viruses type 1 (HSV-1) and type 2 (HSV-2) have co-evolved with humans for thousands of years and are present at a high prevalence in the population worldwide. HSV infections are responsible for several illnesses including skin and mucosal lesions, blindness and even life-threatening encephalitis in both, immunocompetent and immunocompromised individuals of all ages. Therefore, diseases caused by HSVs represent significant public health burdens. Similar to other herpesviruses, HSV-1 and HSV-2 produce lifelong infections in the host by establishing latency in neurons and sporadically reactivating from these cells, eliciting recurrences that are accompanied by viral shedding in both, symptomatic and asymptomatic individuals. The ability of HSVs to persist and recur in otherwise healthy individuals is likely given by the numerous virulence factors that these viruses have evolved to evade host antiviral responses. Here, we review and discuss molecular mechanisms used by HSVs to evade early innate antiviral responses, which are the first lines of defense against these viruses. A comprehensive understanding of how HSVs evade host early antiviral responses could contribute to the development of novel therapies and vaccines to counteract these viruses.

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.

Tenofovir 1% vaginal gel for prevention of HIV-1 infection in women in South Africa (FACTS-001): a phase 3, randomised, double-blind, placebo-controlled trial

BACKGROUND

Young women in southern Africa have substantial risk of HIV acquisition. Female-controlled biomedical interventions are needed to mitigate this risk. We aimed to assess the safety and efficacy of a pericoitally applied tenofovir 1% gel.

METHODS

We did a phase 3, double-blind, randomised, placebo-controlled trial at nine community-based clinical trial sites in South Africa to evaluate the safety and efficacy of tenofovir 1% gel. Sexually active women who were HIV negative and aged 18-30 years were enrolled. Participants were randomly assigned (1:1) using sequential participant numbers to either tenofovir 1% gel or a placebo gel (one dose within 12 h before sex and one dose within 12 h after sex [BAT-24 regimen]), using dynamic permuted block sizes of 8 and 16 within each site. Women received monthly HIV-1 testing, risk reduction support, physical examinations, and product dispensing for up to 27 months. The primary efficacy outcome was incident HIV infection and the primary safety outcome was occurrence of grade 2-4 adverse events, both analysed in the modified intention-to-treat population. To assess the efficacy of tenofovir gel, the cumulative probability of HIV infection was calculated for each treatment using the Kaplan-Meier method. This trial is registered with ClinicalTrials.gov, number NCT01386294.

FINDINGS

From Oct 11, 2011, to Aug 29, 2014, 3844 women were screened, 2059 enrolled, and 2029 included in the primary analysis (1032 in the tenofovir group and 1027 in the placebo group); 39 (4%) in the tenofovir group and 36 (4%) in the placebo group were lost to follow-up. 123 HIV-1 infections occurred over 3036 woman-years of observation; 61 in the tenofovir group (HIV incidence 4·0 per 100 woman-years, 95% CI 3·1-5·2) and 62 in the placebo group (4·0 per 100 woman-years, 3·1-5·2; incidence rate ratio [IRR] 0·98, 95% CI 0·7-1·4). A higher incidence of grade 2 adverse events was observed in the tenofovir group than in the placebo group (IRR 1·09, 95% CI 1·0-1·2; p=0·02). The most common grade 2 or higher product-related adverse events were hypophosphataemia (n=22 for tenofovir vs n=22 for placebo), genital symptoms (n=6 for tenofovir vs n=2 for placebo), or elevated transaminases (n=2 for tenofovir vs n=2 for placebo). No product-related serious adverse events were reported, and no differences in product-related adverse events (p=0·78), grade 3 events (p=0·64), or grade 4 events (p=0·74) were observed between treatment groups.

INTERPRETATION

Overall, pericoital tenofovir gel did not prevent HIV-1 acquisition in this population of young women at risk of HIV infection in South Africa. Alternate safe and effective products that are less user dependent than this product or do not require high adherence are needed.

FUNDING

The US Agency for International Development (USAID), the Bill & Melinda Gates Foundation, and the South African Department of Science and Technology and Department of Health.

Antiviral Activity of Tannic Acid Modified Silver Nanoparticles: Potential to Activate Immune Response in Herpes Genitalis

(1) Background: Tannic acid is a plant-derived polyphenol showing antiviral activity mainly because of an interference with the viral adsorption. In this work, we tested whether the modification of silver nanoparticles with tannic acid (TA-AgNPs) can provide a microbicide with additional adjuvant properties to treat genital herpes infection. (2) Methods: The mouse model of the vaginal herpes simplex virus 2 (HSV-2) infection was used to test immune responses after treatment of the primary infection with TA-AgNPs, and later, after a re-challenge with the virus. (3) Results: The mice treated intravaginally with TA-AgNPs showed better clinical scores and lower virus titers in the vaginal tissues soon after treatment. Following a re-challenge, the vaginal tissues treated with TA-AgNPs showed a significant increase in the percentages of IFN-gamma+ CD8+ T-cells, activated B cells, and plasma cells, while the spleens contained significantly higher percentages of IFN-gamma+ NK cells and effector-memory CD8+ T cells in comparison to NaCl-treated group. TA-AgNPs-treated animals also showed significantly better titers of anti-HSV-2 neutralization antibodies in sera; and (4) Conclusions: Our findings suggest that TA-AgNPs sized 33 nm can be an effective anti-viral microbicide to be applied upon the mucosal tissues with additional adjuvant properties enhancing an anti-HSV-2 immune response following secondary challenge.

Herpes Simplex Virus Suppressive Therapy in Herpes Simplex Virus-2/Human Immunodeficiency Virus-1 Coinfected Women Is Associated With Reduced Systemic CXCL10 But Not Genital Cytokines

BACKGROUND

Herpes simplex virus type-2 (HSV-2) may heighten immune activation and increase human immunodeficiency virus 1 (HIV-1) replication, resulting in greater infectivity and faster HIV-1 disease progression. An 18-week randomized, placebo-controlled crossover trial of 500 mg valacyclovir twice daily in 20 antiretroviral-naive women coinfected with HSV-2 and HIV-1 was conducted and HSV-2 suppression was found to significantly reduce both HSV-2 and HIV-1 viral loads both systemically and the endocervical compartment.

METHODS

To determine the effect of HSV-2 suppression on systemic and genital mucosal inflammation, plasma specimens, and endocervical swabs were collected weekly from volunteers in the trial and cryopreserved. Plasma was assessed for concentrations of 31 cytokines and chemokines; endocervical fluid was eluted from swabs and assayed for 14 cytokines and chemokines.

RESULTS

Valacyclovir significantly reduced plasma CXCL10 but did not significantly alter other cytokine concentrations in either compartment.

CONCLUSIONS

These data suggest genital tract inflammation in women persists despite HSV-2 suppression, supporting the lack of effect on transmission seen in large scale efficacy trials. Alternative therapies are needed to reduce persistent mucosal inflammation that may enhance transmission of HSV-2 and HIV-1.

Factors Driving the HIV Epidemic in Southern Africa

The HIV pandemic has disproportionately impacted sub-Saharan Africa and Southern Africa in particular. The concurrent presence of overlapping epidemic drivers likely underpins how and why the HIV epidemic is so explosive in this region, with implications for understanding approaches to reduce transmission. In this review, we discuss the relative contribution and interaction between epidemic drivers in the Southern African context, including factors both distally and proximally associated with the likelihood and degree of exposure to HIV and factors that increase the probability of transmission when exposure occurs. In particular, we focus on young women as a key population in need of HIV prevention and highlight factors that increase their risk on several levels.

Meeting report: Initial World Health Organization consultation on herpes simplex virus (HSV) vaccine preferred product characteristics, March 2017

The development of vaccines against herpes simplex virus (HSV) is an important global goal for sexual and reproductive health. A key priority to advance development of HSV vaccines is the definition of preferred product characteristics (PPCs), which provide strategic guidance on World Health Organization (WHO) preferences for new vaccines, specifically from a low- and middle-income country (LMIC) perspective. To start the PPC process for HSV vaccines, the WHO convened a global stakeholder consultation in March 2017, to define the priority public health needs that should be addressed by HSV vaccines and discuss the key considerations for HSV vaccine PPCs, particularly for LMICs. Meeting participants outlined an initial set of overarching public health goals for HSV vaccines in LMICs, which are: to reduce the acquisition of HIV associated with HSV-2 infection in high HIV-prevalence populations and to reduce the burden of HSV-associated disease, including mortality and morbidity due to neonatal herpes and impacts on sexual and reproductive health. Participants also considered the role of prophylactic versus therapeutic vaccines, whether both HSV-2 and HSV-1 should be targeted, important target populations, and infection and disease endpoints for clinical trials. This article summarizes the main discussions from the consultation.

Preventing HIV infection without targeting the virus: how reducing HIV target cells at the genital tract is a new approach to HIV prevention

For over three decades, HIV infection has had a tremendous impact on the lives of individuals and public health. Microbicides and vaccines studies have shown that immune activation at the genital tract is a risk factor for HIV infection. Furthermore, lower level of immune activation, or what we call immune quiescence, has been associated with a lower risk of HIV acquisition. This unique phenotype is observed in highly-exposed seronegative individuals from different populations including female sex workers from the Pumwani cohort in Nairobi, Kenya. Here, we review the link between immune activation and susceptibility to HIV infection. We also describe a new concept in prevention where, instead of targeting the virus, we modulate the host immune system to resist HIV infection. Mimicking the immune quiescence phenotype might become a new strategy in the toolbox of biomedical methods to prevent HIV infection. Clinical trial registration on clinicaltrial.gov: #NCT02079077.

Association of HPV infection and clearance with cervicovaginal immunology and the vaginal microbiota

Cervical human papillomavirus (HPV) infection may increase HIV risk. Since other genital infections enhance HIV susceptibility by inducing inflammation, we assessed the impact of HPV infection and clearance on genital immunology and the cervico-vaginal microbiome. Genital samples were collected from 65 women for HPV testing, immune studies and microbiota assessment; repeat HPV testing was performed after 6 months. All participants were HIV-uninfected and free of bacterial STIs. Cytobrush-derived T cell and dendritic cell subsets were assessed by multiparameter flow cytometry. Undiluted cervico-vaginal secretions were used to determine cytokine levels by multiplex ELISA, and to assess bacterial community composition and structure by 16S rRNA gene sequence analysis. Neither HPV infection nor clearance were associated with broad differences in cervical T cell subsets or cytokines, although HPV clearance was associated with increased Langerhans cells and HPV infection with elevated IP-10 and MIG. Individuals with HPV more frequently had a high diversity cervico-vaginal microbiome (community state type IV) and were less likely to have an L. gasseri predominant microbiome. In summary, HPV infection and/or subsequent clearance was not associated with inflammation or altered cervical T cell subsets, but associations with increased Langerhans cells and the composition of the vaginal microbiome warrant further exploration.

Ex vivo 2D and 3D HSV-2 infection model using human normal vaginal epithelial cells

Herpes simplex virus type 2 (HSV-2) infects human genital mucosa and establishes life-long latent infection. It is unmet need to establish a human cell-based microphysiological system for virus biology and anti-viral drug discovery. One of barriers is lacking of culture system of normal epithelial cells in vitro over decades. In this study, we established human normal vaginal epithelial cell (HNVEC) culture using co-culture system. HNVEC cells were then propagated rapidly and stably in a defined culture condition. HNVEC cells exhibited a normal diploid karyotype and formed the well-defined and polarized spheres in matrigel three-dimension (3D) culture, while malignant cells (HeLa) formed disorganized and nonpolar solid spheres. HNVEC cells had a normal cellular response to DNA damage and had no transforming property using soft agar assays. HNVEC expressed epithelial marker cytokeratin 14 (CK14) and p63, but not cytokeratin 18 (CK18). Next, we reconstructed HNVEC-derived 3D vaginal epithelium using air-liquid interface (ALI) culture. This 3D vaginal epithelium has the basal and apical layers with expression of epithelial markers as its originated human vaginal tissue. Finally, we established an HSV-2 infection model based on the reconstructed 3D vaginal epithelium. After inoculation of HSV-2 (G strain) at apical layer of the reconstructed 3D vaginal epithelium, we observed obvious pathological effects gradually spreading from the apical layer to basal layer with expression of a viral protein. Thus, we established an ex vivo 2D and 3D HSV-2 infection model that can be used for HSV-2 virology and anti-viral drug discovery.

Distinct Effects of the Cervicovaginal Microbiota and Herpes Simplex Type 2 Infection on Female Genital Tract Immunology

Background

Genital inflammation is a key determinant of human immunodeficiency virus (HIV) transmission, and may increase HIV-susceptible target cells and alter epithelial integrity. Several genital conditions that increase HIV risk are more prevalent in African, Caribbean, and other black (ACB) women, including bacterial vaginosis and herpes simplex virus type-2 (HSV-2) infection. Therefore, we assessed the impact of the genital microbiota on mucosal immunology in ACB women and microbiome-HSV-2 interactions.

Methods

Cervicovaginal secretions and endocervical cells were collected by cytobrush and Instead Softcup, respectively. T cells and dendritic cells were assessed by flow cytometry, cytokines by multiplex enzyme-linked immunosorbent assay (ELISA), and the microbiota by 16S ribosomal ribonucleic acid gene sequencing.

Results

The cervicovaginal microbiota of 51 participants were composed of community state types (CSTs) showing diversity (20/51; 39%) or predominated by Lactobacillus iners (22/51; 42%), L. crispatus (7/51; 14%), or L. gasseri (2/51; 4%). High-diversity CSTs and specific bacterial phyla (Gardnerella vaginalis and Prevotella bivia) were strongly associated with cervicovaginal inflammatory cytokines, but not with altered endocervical immune cells. However, cervical CD4+ T-cell number was associated with HSV-2 infection and a distinct cytokine profile.

Conclusions

This suggests that the genital microbiota and HSV-2 infection may influence HIV susceptibility through independent biological mechanisms.

Epidemiology of high-risk human papillomavirus and cervical lesions in African women living with HIV/AIDS: effect of anti-retroviral therapy

OBJECTIVE

To describe the effect of antiretroviral therapy (ART) and HIV-related factors on high-risk human papillomavirus (HR-HPV) and high-grade cervical intraepithelial neoplasia lesions (CIN2+) among women living with HIV/AIDS (WLHA) in sub-Saharan Africa.

DESIGN

Prospective cohort of WLHA in Ouagadougou, Burkina Faso (BF) and Johannesburg, South Africa (SA). Recruitment was stratified by ART status.

METHODS

At baseline and endline (median 16 months), cervical samples, and biopsies were analyzed for HPV genotyping (InnoLiPA) and by histology. Logistic regression was used to estimate associations of ART and HIV-related factors with HR-HPV and CIN2+ outcomes, and all results presented are adjusted for baseline CD4 cell count.

RESULTS

Among 1238 enrolled WLHA (BF = 615; SA = 623), HR-HPV prevalence was 59.1% in BF and 79.1% in SA. CIN2+ prevalence was 5.8% in BF and 22.5% in SA. Compared with long-duration ART users (>2 years), HR-HPV prevalence was higher among short-duration ART users [≤2 years; adjusted prevalence ratio (aPR) = 1.24, 95% confidence interval (CI) 1.04-1.47] in BF, and CIN2+ prevalence was higher among short-duration ART users [adjusted odds ratio (aOR) = 1.99, 95% CI 1.12-3.54) and ART-naive participants (aOR = 1.87, 95% CI 1.11-3.17) in SA. Among 963 (77.8%) women seen at endline, HR-HPV persistence was 41.1% in BF and 30.2% in SA; CIN2+ incidence over 16-months was 1.2% in BF and 5.8% in SA. HR-HPV persistence was associated with being ART-naive in BF (aPR = 1.89, 95% CI 1.26-2.83), and with short-duration ART use (aPR = 1.78, 95% CI 1.11-2.86) and HIV-1 plasma viral load at least 1000 copies/ml (aPR = 2.87, 95% CI 1.63-5.05) in SA. CIN2+ incidence was reduced among women on ART in SA (aOR = 0.39, 95% CI 0.15-1.01).

CONCLUSION

Prolonged and effective ART is important in controlling HR-HPV and the development of CIN2+.

Genital inflammation, immune activation and risk of sexual HIV acquisition

PURPOSE OF REVIEW

Women who have genital inflammation are at increased risk of sexual HIV infection. The purpose of this review is to evaluate the mechanisms for this relationship, causes of genital inflammation, and strategies to manage this condition.

RECENT FINDINGS

We have recently shown in a cohort of South African women that HIV seroconversion was associated with persistently raised genital inflammatory cytokines (including MIP-1α, MIP-1β, and IP-10). Elevated inflammatory cytokine concentrations may facilitate HIV infection by recruiting and activating HIV target cells and disrupting the mucosal epithelial barrier. Bacterial vaginosis and sexually transmitted infections (STIs), which are predominantly asymptomatic in women, cause lower genital tract inflammation and increased HIV acquisition risk. In Africa, where syndromic management of STIs and bacterial vaginosis is standard-of-care, the substantial burden of asymptomatic infections has likely contributed to high-HIV incidence rates.

SUMMARY

A genital inflammatory profile contributes to the high risk of HIV acquisition in African women. STIs and bacterial vaginosis are poorly managed in Africa and other developing nations and as such remain major drivers of persistent genital inflammation and HIV acquisition among these women.

Seroprevalence and Co-Infection of Human Immunodeficiency Virus (HIV) and Herpes Simplex Virus (HSV) Among Pregnant Women in Lokoja, North-Central Nigeria

Background

Herpes simplex virus 1 (HSV-1) is normally associated with orofacial (orolabial) infections and encephalitis, whereas HSV-2 usually causes genital infections and can be transmitted from infected mothers to neonates. The evidence suggesting that HSV is facilitating the spread of the global human immunodeficiency virus (HIV) epidemic and the risk posed by these synergies to neonates in developing countries informed this study.

Objectives

To determine the seroprevalence and co-infection of HIV and HSV, as well as their associated risk factors, in Lokoja, Nigeria.

Methods

This was a hospital-based cross-sectional, prospective study, which was carried out among pregnant women attending the antenatal clinic at the federal medical centre in Lokoja, Nigeria. sociodemographic characteristics and HIV-HSV status were determined by the use of a structured questionnaire and immunoassay kits, respectively. All data were analyzed using Stata statistical software (version 12), and the level of significance was determined to be P < 0.05 using the chi-square test.

Results

Of the 250 pregnant women screened for HIV and HSV, 154 (61.6%) were in the 2nd trimester of gestation, and all of the co-infected respondents were in their 2nd trimester. Only six (2.4%) of the respondents tested positive for HIV, with all six (100%) showing positivity for HSV so the co-infection rate was six (2.4%). Co-infection was found to occur between the ages of 15 and 35 years, while higher age groups did not show any co-infection. Parity, level of education, and history of painful genital ulcers had no significant association with co-infection.

Conclusions

Advocacy and publicity to raise awareness of the potential public health impact of HSV and HIV co-infection in Nigeria, where anti-HSV testing is not generally performed in all populations, is therefore recommended.

Current Concepts for Genital Herpes Simplex Virus Infection: Diagnostics and Pathogenesis of Genital Tract Shedding

Herpes simplex virus 2 (HSV-2) is a DNA virus that is efficiently transmitted through intimate genital tract contact and causes persistent infection that cannot be eliminated. HSV-2 may cause frequent, symptomatic self-limited genital ulcers, but in most persons infection is subclinical. However, recent studies have demonstrated that the virus is frequently shed from genital surfaces even in the absence of signs or symptoms of clinical disease and that the virus can be transmitted during these periods of shedding. Furthermore, HSV-2 shedding is detected throughout the genital tract and may be associated with genital tract inflammation, which likely contributes to increased risk of HIV acquisition. This review focuses on HSV diagnostics, as well as what we have learned about the importance of frequent genital HSV shedding for (i) HSV transmission and (ii) genital tract inflammation, as well as (iii) the impact of HSV-2 infection on HIV acquisition and transmission. We conclude with discussion of future areas of research to push the field forward.

Status of vaccine research and development of vaccines for herpes simplex virus

Herpes simplex virus type-1 (HSV-1) and -2 (HSV-2) are highly prevalent global pathogens which commonly cause recurrent oral and genital ulcerations. Less common but more serious complications include meningitis, encephalitis, neonatal infection, and keratitis. HSV-2 infection is a significant driver of the HIV epidemic, increasing the risk of HIV acquisition 3 fold. As current control strategies for genital HSV-2 infection, including antiviral therapy and condom use, are only partially effective, vaccines will be required to reduce infection. Both preventive and therapeutic vaccines for HSV-2 are being pursued and are in various stages of development. We will provide an overview of efforts to develop HSV-2 vaccines, including a discussion of the clinical need for an HSV vaccine, and status of research and development with an emphasis on recent insights from trials of vaccine candidates in clinical testing. In addition, we will touch upon aspects of HSV vaccine development relevant to low and middle income countries.

Inflammation and HIV Transmission in Sub-Saharan Africa

While the per-contact risk of sexual HIV transmission is relatively low, it is fourfold higher in sub-Saharan Africa, and this may partly explain the major global disparities that exist in HIV prevalence. Genital immune parameters are key determinants of HIV transmission risk, including epithelial integrity and the presence of highly HIV-susceptible intraepithelial or submucosal CD4+ T cell target cells. Biological parameters that may enhance mucosal HIV susceptibility in highly HIV-affected regions of sub-Saharan Africa include increased levels of mucosal inflammation, which can affect both epithelial integrity and target cell availability, as well as the increased mucosal surface area that is afforded by an intact foreskin, contraceptive choices, and intravaginal practices. There are multifactorial causes for increased mucosal inflammation, with the prevalence and nature of common co-infections being particularly relevant.

Immune Activation in the Female Genital Tract: Expression Profiles of Soluble Proteins in Women at High Risk for HIV Infection

Soluble cervicovaginal biomarkers of inflammation, immune activation and risk of HIV acquisition are needed to reliably assess the safety of new biomedical prevention strategies including vaccines and microbicides. However, a fuller understanding of expression profiles in women at high risk for HIV infection is crucial to the effective use of these potential biomarkers in Phase 3 trial settings. We have measured 45 soluble proteins and peptides in cervicovaginal lavage samples from 100 HIV negative women at high risk for HIV infection. Women were followed over one menstrual cycle to investigate modulation by hormonal contraception, menstrual cycle phase, recent sexual exposure and intravaginal practices. Women using injectable DMPA had increased concentration of several soluble proteins of the innate and adaptive immune system, including IL-1α, IL-1β, IL-2, MIP-1β, IP-10, IL-8, TGF-β, HBD4, IgA, IgG1, and IgG2. Women using combined oral contraceptives had a similar signature. There were differences in concentrations among samples from post-ovulation compared to pre-ovulation, notably increased immunoglobulins. Increased prostate-specific antigen, indicative of recent sexual exposure, was correlated with increased IL-6, MCP-1, and SLPI, and decreased GM-CSF and HBD3. The identified signature profiles may prove critical in evaluating the potential safety and impact on risk of HIV acquisition of different biomedical intervention strategies.

Chlamydial Pre-Infection Protects from Subsequent Herpes Simplex Virus-2 Challenge in a Murine Vaginal Super-Infection Model

Chlamydia trachomatis and Herpes Simplex Virus-2 (HSV-2) genital tract co-infections have been reported in humans and studied in vitro but the clinical consequences are unknown. Limited epidemiologic evidence suggests that these co-infections could be more severe than single infections of either pathogen, but the host-pathogen interactions during co-infection remain uncharacterized. To determine whether disease progression and/or pathogen shedding differs between singly-infected and super-infected animals, we developed an in vivo super-infection model in which female BALB/c mice were vaginally infected with Chlamydia muridarum (Cm) followed later by HSV-2. Pre-infection with Chlamydia 3 or 9 days prior to HSV-2 super-infection conferred significant protection from HSV-2-induced neurologic disease and significantly reduced viral recovery compared to HSV-2 singly-infected controls. Neither protection from mortality nor reduced viral recovery were observed when mice were i) super-infected with HSV-2 on day 27 post Cm; ii) infected with UV-irradiated Cm and super-infected with HSV-2; or iii) azithromycin-treated prior to HSV-2 super-infection. Therefore, protection from HSV-2-induced disease requires active infection with viable chlamydiae and is not observed after chlamydial shedding ceases, either naturally or due to antibiotic treatment. Thus, Chlamydia-induced protection is transient and requires the continued presence of chlamydiae or their components. These data demonstrate that chlamydial pre-infection can alter progression of subsequent HSV-2 infection, with implications for HSV-2 transmission from co-infected humans.

Human Herpesviruses as Copathogens of HIV Infection, Their Role in HIV Transmission, and Disease Progression

Of eight human herpesviruses (HHVs), often, only herpes simplex virus types 1 (HSV-1) and 2 (HSV-2) find mention in medical literature as both of these viruses are commonly associated with genital lesions and oral ulcers, commonly known as cold sores. However, role of human herpesviruses as copathogens and in aggravation and in the transmission of other human diseases, especially the Acquired immunodeficiency syndrome (HIV/AIDS) has only very recently been recognized. Therefore, screening and treating subclinical HHV infections may offer slowing of HIV infection, disease progression, and its transmission. Beside HSV-1 and HSV-2, HHV-3 a causative agent of herpes zoster remained one of the first manifestations of HIV disease before the era of highly active antiretroviral therapy (HAART). HHV-5 also known as human Cytomegalovirus infection remains a significant risk factor for HIV-associated mortality and morbidity even in HAART era. It is proposed that Cytomegalovirus viremia could be a better predictor of HIV disease progression than CD4+ T-lymphocyte count. The role of HHV-4 or Epstein-Burr virus and HHV-6, HHV-7, and HHV-8 is still being investigated in HIV disease progression. This review provides insight into the current understanding about these 8 HHVs, their co-pathogenesis, and role in HIV/AIDS disease progression. The review also covers recent literature in favor and against administering anti-HHV treatment along with HAART for slower AIDS progression and interrupted sexual transmission.

Herpes Simplex Virus Type-2 Cervicovaginal Shedding Among Women Living With HIV-1 and Receiving Antiretroviral Therapy in Burkina Faso: An 8-Year Longitudinal Study

Background. The impact of antiretroviral therapy (ART) on herpes simplex virus type-2 (HSV-2) replication is unclear. The aim of this study was to assess factors associated with cervicovaginal HSV-2 DNA shedding and genital ulcer disease (GUD) in a cohort of women living with human immunodeficiency virus type-1 (HIV-1) in Burkina Faso.

Methods. Participants were screened for cervicovaginal HSV-2 DNA, GUD, cervicovaginal and systemic HIV-1 RNA, and reproductive tract infections every 3–6 months over 8 years. Associations with HSV-2 shedding and quantity were examined using random-effects logistic and linear regression, respectively.

Results. Of the 236 women with data on HSV-2 shedding, 151 took ART during the study period. Cervicovaginal HSV-2 DNA was detected in 42% of women (99 of 236) in 8.2% of visits (151 of 1848). ART was associated with a reduction in the odds of HSV-2 shedding, which declined for each year of ART use (odds ratio [OR], 0.74; 95% confidence interval [CI], .59–.92). In the multivariable model, the impact of ART was primarily associated with suppression of systemic HIV-1 RNA (adjusted OR, 0.32; 95% CI, .15–.67). A reduction in the odds of GUD was also observed during ART, mainly in those with HIV-1 suppression (adjusted OR, 0.53; 95% CI, .25–1.11).

Conclusions. ART is strongly associated with a decrease in cervicovaginal HSV-2 shedding, and the impact was sustained over several years.

Schistosoma mansoni Infection in Ugandan Men Is Associated with Increased Abundance and Function of HIV Target Cells in Blood, but Not the Foreskin: A Cross-sectional Study

Background

Schistosoma mansoni infection has been associated with an increased HIV prevalence in humans and SHIV incidence in primate models. We hypothesized that immune activation from this gastrointestinal mucosa infection would increase highly HIV-susceptible CD4 T cell subsets in the blood and the foreskin through common mucosal homing.

Methodology/Principal Findings

Foreskin tissue and blood were obtained from 34 HIV- and malaria-uninfected Ugandan men who volunteered for elective circumcision, 12 of whom were definitively positive for S. mansoni eggs in stool and 12 definitively negative for both S. mansoni eggs and worm antigen. Tissue and blood T cell subsets were characterized by flow cytometry and immunohistochemistry (IHC). Th17 and Th1 cells from both the blood and foreskin expressed higher levels of CCR5 and were more activated than other CD4 T cell subsets. S. mansoni-infected men had a higher frequency of systemic Th1 cells (22.9 vs. 16.5% of blood CD4 T cells, p<0.05), Th17 cells (2.3 vs. 1.5%, p<0.05), and Th22 cells (0.5 vs. 0.3%, p<0.01) than uninfected men. Additionally, Th17 cells in the blood of S. mansoni-infected men demonstrated enhanced function (28.1 vs. 16.3% producing multiple cytokines, p = 0.046). However, these immune alterations were not observed in foreskin tissue.

Conclusions/Significance

S. mansoni infection was associated with an increased frequency of highly HIV-susceptible Th1, Th17 and Th22 cell subsets in the blood, but these T cell immune differences did not extend to the foreskin. S. mansoni induced changes in T cell immunology mediated through the common mucosal immune system are not likely to increase HIV susceptibility in the foreskin.

Fishing communities in East Africa have a very high prevalence of HIV, and also high rates of other endemic infections such as malaria and the fluke Schistosoma mansoni. Genital infections are known to increase HIV susceptibility through the recruitment and activation of mucosal CD4 T cells to the site of HIV sexual exposure. These activated CD4 T cells are necessary for an effective host immune response but are also preferentially infected by HIV. We hypothesized that S. mansoni infection in the gut mucosa might increase recruitment and activation of HIV target cells at other mucosal sites, and thereby contribute to high HIV rates in fishing communities. We enrolled men from a fishing community in Uganda and examined the frequency of highly HIV-susceptible cell types in their blood and foreskin tissue (a main site of HIV acquisition in heterosexual men). We found that men with S. mansoni infection had a greater frequency of HIV target cells in their blood, but not their foreskin tissue, perhaps because foreskin cells did not express mucosal homing markers. It is possible that HIV target cells observed in the blood of S. mansoni-infected individuals may traffic to other mucosae, such as the vagina or gut, and so the possibility that S. mansoni infection increases risk at these sites should be explored.

The Vaginal Acquisition and Dissemination of HIV-1 Infection in a Novel Transgenic Mouse Model Is Facilitated by Coinfection with Herpes Simplex Virus 2 and Is Inhibited by Microbicide Treatment

Epidemiological studies have demonstrated that herpes simplex virus 2 (HSV-2) infection significantly increases the risk of HIV-1 acquisition, thereby contributing to the expanding HIV-1 epidemic. To investigate whether HSV-2 infection directly facilitates mucosal HIV-1 acquisition, we used our transgenic hCD4/R5/cT1 mouse model which circumvents major entry and transcription blocks preventing murine HIV-1 infection by targeting transgenic expression of human CD4, CCR5, and cyclin T1 genes to CD4(+) T cells and myeloid-committed cells. Productive infection of mucosal leukocytes, predominantly CD4(+) T cells, was detected in all hCD4/R5/cT1 mice intravaginally challenged with an HIV-1 infectious molecular clone, HIV-Du151.2env-NLuc, which expresses an env gene (C.Du151.2) cloned from an acute heterosexually infected woman and a NanoLuc luciferase reporter gene. Lower genital tract HIV-1 infection after HIV-Du151.2env-NLuc intravaginal challenge was increased ~4-fold in hCD4/R5/cT1 mice coinfected with HSV-2. Furthermore, HIV-1 dissemination to draining lymph nodes was detected only in HSV-2-coinfected mice. HSV-2 infection stimulated local infiltration and activation of CD4(+) T cells and dendritic cells, likely contributing to the enhanced HIV-1 infection and dissemination in HSV-2-coinfected mice. We then used this model to demonstrate that a novel gel containing tenofovir disoproxil fumarate (TDF), the more potent prodrug of tenofovir (TFV), but not the TFV microbicide gel utilized in the recent CAPRISA 004, VOICE (Vaginal and Oral Interventions to Control the Epidemic), and FACTS 001 clinical trials, was effective as preexposure prophylaxis (PrEP) to completely prevent vaginal HIV-1 infection in almost half of HSV-2-coinfected mice. These results also support utilization of hCD4/R5/cT1 mice as a highly reproducible immunocompetent preclinical model to evaluate HIV-1 acquisition across the female genital tract.

IMPORTANCE

Multiple epidemiological studies have reported that genital herpes simplex virus 2 (HSV-2) infection increases the risk of HIV-1 sexual acquisition by severalfold. Understanding the underlying mechanisms by which HSV-2 facilitates HIV-1 infection and optimizing the efficacy of therapies to inhibit HIV-1 infection during HSV-2 coinfection should contribute to reducing HIV-1 transmission. Using our novel transgenic hCD4/R5/cT1 mouse model infectible with HIV-1, we demonstrated that HSV-2 infection enhances vaginal transmission and dissemination of HIV-1 infection while stimulating recruitment and activation of CD4(+) T cells and dendritic cells in the lower genital tract. HIV acquisition by hCD4/R5/cT1 mice vaginally coinfected with HSV-2 could be completely prevented in almost half the mice by preexposure prophylaxis (PrEP) with a novel gel containing tenofovir disoproxil fumarate (TDF), the tenofovir prodrug, but not with the tenofovir microbicide gel utilized in CAPRISA-004, VOICE, and FACTS-001 clinical trials. The hCD4/R5/cT1 mice represent a new preclinical mouse model to evaluate vaginal HIV-1 acquisition.

The Low-Cost Compound Lignosulfonic Acid (LA) Exhibits Broad-Spectrum Anti-HIV and Anti-HSV Activity and Has Potential for Microbicidal Applications

Objectives

Lignosulfonic acid (LA), a low-cost lignin-derived polyanionic macromolecule, was extensively studied for its anti-HIV and anti-HSV activity in various cellular assays, its mechanism of viral inhibition and safety profile as potential microbicide.

Results

LA demonstrated potent inhibitory activity of HIV replication against a wide range of R5 and X4 HIV strains and prevented the uptake of HIV by bystander CD4⁺ T cells from persistently infected T cells in vitro (IC₅₀: 0.07 – 0.34 μM).

LA also inhibited HSV-2 replication in vitro in different cell types (IC₅₀: 0.42 – 1.1 μM) and in rodents in vivo. Furthermore, LA neutralized the HIV-1 and HSV-2 DC-SIGN-mediated viral transfer to CD4⁺ T cells (IC₅₀: ∼1 μM). In addition, dual HIV-1/HSV-2 infection in T cells was potently blocked by LA (IC₅₀: 0.71 μM). No antiviral activity was observed against the non-enveloped viruses Coxsackie type B4 and Reovirus type 1.

LA is defined as a HIV entry inhibitor since it interfered with gp120 binding to the cell surface of T cells. Pretreatment of PBMCs with LA neither increased expression levels of cellular activation markers (CD69, CD25 and HLA-DR), nor enhanced HIV-1 replication. Furthermore, we found that LA had non-antagonistic effects with acyclovir, PRO2000 or LabyA1 (combination index (CI): 0.46 – 1.03) in its anti-HSV-2 activity and synergized with tenofovir (CI: 0.59) in its anti-HIV-1 activity. To identify mechanisms of LA resistance, we generated in vitro a mutant HIV-1 NL4.3^LAresistant virus, which acquired seven mutations in the HIV-1 envelope glycoproteins: S160N, V170N, Q280H and R389T in gp120 and K77Q, N113D and H132Y in gp41. Additionally, HIV-1 NL4.3^LAresistant virus showed cross-resistance with feglymycin, enfuvirtide, PRO2000 and mAb b12, four well-described HIV binding/fusion inhibitors. Importantly, LA did not affect the growth of vaginal Lactobacilli strains.

Conclusion

Overall, these data highlight LA as a potential and unique low-cost microbicide displaying broad anti-HIV and anti-HSV activity.

Herpes simplex virus type 2-infected dendritic cells produce TNF-α, which enhances CCR5 expression and stimulates HIV production from adjacent infected cells

Prior HSV-2 infection enhances the acquisition of HIV-1 >3-fold. In genital herpes lesions, the superficial layers of stratified squamous epithelium are disrupted, allowing easier access of HIV-1 to Langerhans cells (LC) in the epidermis and perhaps even dendritic cells (DCs) in the outer dermis, as well as to lesion infiltrating activated T lymphocytes and macrophages. Therefore, we examined the effects of coinfection with HIV-1 and HSV-2 on monocyte-derived DCs (MDDC). With simultaneous coinfection, HSV-2 significantly stimulated HIV-1 DNA production 5-fold compared with HIV-1 infection alone. Because <1% of cells were dually infected, this was a field effect. Virus-stripped supernatants from HSV-2-infected MDDCs were shown to enhance HIV-1 infection, as measured by HIV-1-DNA and p24 Ag in MDDCs. Furthermore these supernatants markedly stimulated CCR5 expression on both MDDCs and LCs. TNF-α was by far the most prominent cytokine in the supernatant and also within HSV-2-infected MDDCs. HSV-2 infection of isolated immature epidermal LCs, but not keratinocytes, also produced TNF-α (and low levels of IFN-β). Neutralizing Ab to TNF-α and its receptor, TNF-R1, on MDDCs markedly inhibited the CCR5-stimulating effect of the supernatant. Therefore, these results suggest that HSV-2 infection of DCs in the skin during primary or recurrent genital herpes may enhance HIV-1 infection of adjacent DCs, thus contributing to acquisition of HIV-1 through herpetic lesions.

Evasion of early antiviral responses by herpes simplex viruses

Besides overcoming physical constraints, such as extreme temperatures, reduced humidity, elevated pressure, and natural predators, human pathogens further need to overcome an arsenal of antimicrobial components evolved by the host to limit infection, replication and optimally, reinfection. Herpes simplex virus-1 (HSV-1) and herpes simplex virus-2 (HSV-2) infect humans at a high frequency and persist within the host for life by establishing latency in neurons. To gain access to these cells, herpes simplex viruses (HSVs) must replicate and block immediate host antiviral responses elicited by epithelial cells and innate immune components early after infection. During these processes, infected and noninfected neighboring cells, as well as tissue-resident and patrolling immune cells, will sense viral components and cell-associated danger signals and secrete soluble mediators. While type-I interferons aim at limiting virus spread, cytokines and chemokines will modulate resident and incoming immune cells. In this paper, we discuss recent findings relative to the early steps taking place during HSV infection and replication. Further, we discuss how HSVs evade detection by host cells and the molecular mechanisms evolved by these viruses to circumvent early antiviral mechanisms, ultimately leading to neuron infection and the establishment of latency.

Early HIV-1 infection is associated with reduced frequencies of cervical Th17 cells

BACKGROUND

The hallmark of HIV infection is progressive but variable rates of systemic and mucosal CD4 depletion, leading to immunodeficiency. The impact of early HIV infection on cervical CD4 T-cell populations in humans remains poorly described.

METHODS

We analyzed cytobrush-derived immune cells by flow cytometry and cytokines in cervicovaginal lavage from participants in early HIV (<6 months postinfection), chronic HIV, and HIV-uninfected controls.

RESULTS

CD4:CD8 ratios declined rapidly in both the cervix and the blood following HIV infection. In contrast, absolute cervical CD4 T-cell counts in early HIV were comparable to HIV-uninfected participants, declining only in chronic infection. Early HIV infection was associated with increases in RANTES and MIP3a in cervicovaginal fluids. Concurrently, slight increases in activated cells (CD38HLA-DR) and higher levels of CTLA4 expression on Tregs in the cervix were observed. Although study groups did not differ with respect to levels of CCR5, integrin B7, or CD69, the frequencies of Th17 cells (defined as CCR6CCR10) was reduced by >10-fold in early HIV infection and Th1 cells (defined as CCR6CXCR3) were reduced by >2-fold. Although CCR6CCR10 cells did not differ in HIV receptor expression, these cells produced higher levels of interferon gamma and interleukin 17.

CONCLUSIONS

These data support the model of initial CD4 T-cell depletion followed by overall T-cell influx in response to infection and concomitant increases in immune activation, inflammation, and regulatory markers. These data are among the earliest characterization of the cellular milieu in the female genital tract following male-to-female HIV transmission.

Persistence of mucosal T-cell responses to herpes simplex virus type 2 in the female genital tract

Relatively little is known about the human T-cell response to herpes simplex virus type 2 (HSV-2) in the female genital tract, a major site of heterosexual HSV-2 acquisition, transmission, and reactivation. In order to understand the role of local mucosal immunity in HSV-2 infection, T-cell lines were expanded from serial cervical cytobrush samples from 30 HSV-2-infected women and examined for reactivity to HSV-2. Approximately 3% of the CD3+ T cells isolated from the cervix were HSV-2 specific and of these, a median of 91.3% were CD4+, whereas a median of 3.9% were CD8+. HSV-2-specific CD4+ T cells expanded from the cervix were not only more frequent than CD8+ T cells but also exhibited greater breadth in terms of antigenic reactivity. T cells directed at the same HSV-2 protein were often detected in serial cervical cytobrush samples and in blood. Thus, broad and persistent mucosal T-cell responses to HSV-2 were detected in the female genital tract of HSV-2+ women suggesting that these cells are resident at the site of HSV-2 infection. Understanding the role of these T cells at this biologically relevant site will be central to the elucidation of adaptive immune mechanisms involved in controlling HSV-2 disease.

Nanotech-derived topical microbicides for HIV prevention: the road to clinical development

More than three decades since its discovery, HIV infection remains one of the most aggressive epidemics worldwide, with more than 35 million people infected. In sub-Saharan Africa, heterosexual transmissions represent nearly 80% of new infections, with 50% of these occurring in women. In an effort to stop the dramatic spread of the HIV epidemic, new preventive treatments, such as microbicides, have been developed. Nanotechnology has revolutionized this field by designing and engineering novel highly effective nano-sized materials as microbicide candidates. This review illustrates the most recent advances in nanotech-derived HIV prevention strategies, as well as the main steps required to translate promising in vitro results into clinical trials.

Herpes simplex virus 2 infection: molecular association with HIV and novel microbicides to prevent disease

Infection with herpes simplex viruses is one of the most ancient diseases described to affect humans. Infection with these viruses produces vexing effects to the host, which frequently recur. Infection with herpes simplex viruses is lifelong, and currently there is no vaccine or drug to prevent or cure infection. Prevalence of herpes simplex virus 2 (HSV-2) infection varies significantly depending on the geographical region and nears 20 % worldwide. Importantly, HSV-2 is the first cause of genital ulcers in the planet. HSV-2 affects approximately 500 million people around the globe and significantly increases the likelihood of acquiring the human immunodeficiency virus (HIV), as well as its shedding. Thus, controlling HSV-2 infection and spread is of public health concern. Here, we review the diseases produced by herpes simplex viruses, the factors that modulate HSV-2 infection, the relationship between HSV-2 and HIV and novel therapeutic and prophylactic microbicides/antivirals under development to prevent infection and pathological outcomes produced by this virus. We also review mutations associated with HSV-2 resistance to common antivirals.

Defining genital tract cytokine signatures of sexually transmitted infections and bacterial vaginosis in women at high risk of HIV infection: a cross-sectional study

OBJECTIVES

Sexually transmitted infections (STI) and bacterial vaginosis (BV) cause female genital tract inflammation. This inflammation, which is often present in the absence of symptoms, is associated with increased susceptibility to HIV infection. We aimed to evaluate genital cytokine profiles and the degree of inflammation associated with common STIs and BV.

METHODS

HIV-uninfected women (n=227) were screened for BV, Chlamydia trachomatis, Neisseria gonorrhoeae, Herpes simplex virus type 2 (HSV-2), and Trichomonas vaginalis. Concentrations of 42 cytokines in cervicovaginal lavages and 13 cytokines in plasma were measured using Luminex. Changes in cytokine profiles were evaluated using Mann-Whitney U test, logistic regression and factor analysis. p Values were adjusted for multiple comparisons using a false discovery rate step-down procedure.

RESULTS

Women with chlamydia or gonorrhoea had the highest genital cytokine concentrations, with 17/42 and 14/42 cytokines upregulated compared with women with no infection, respectively. BV was associated with elevated proinflammatory cytokine concentrations, but lower chemokine and haematopoietic cytokine concentrations. HSV-2 reactivation was associated with lower levels of inflammation, while trichomoniasis did not cause significant differences in genital cytokine concentrations. Genital infections did not influence plasma cytokine concentrations. Although certain STIs, in particular chlamydia and gonorrhoea, were associated with high genital cytokine concentrations, only 19% of women with an STI/BV had clinical signs.

CONCLUSIONS

Chlamydia was associated with the highest genital cytokine levels, followed by gonorrhoea, HSV-2, trichomoniasis, and BV. In regions where HIV is prevalent and STIs are managed syndromically, better STI/BV screening is urgently needed, as certain infections were found to be highly inflammatory.

Effect of female genital schistosomiasis and anti-schistosomal treatment on monocytes, CD4+ T-cells and CCR5 expression in the female genital tract

Background

Schistosoma haematobium is a waterborne parasite that may cause female genital schistosomiasis (FGS), characterized by genital mucosal lesions. There is clinical and epidemiological evidence for a relationship between FGS and HIV. We investigated the impact of FGS on HIV target cell density and expression of the HIV co-receptor CCR5 in blood and cervical cytobrush samples. Furthermore we evaluated the effect of anti-schistosomal treatment on these cell populations.

Design

The study followed a case-control design with post treatment follow-up, nested in an on-going field study on FGS.

Methods

Blood and cervical cytobrush samples were collected from FGS negative and positive women for flow cytometry analyses. Urine samples were investigated for schistosome ova by microscopy and polymerase chain reaction (PCR).

Results

FGS was associated with a higher frequency of CD14⁺ cells (monocytes) in blood (11.5% in FGS+ vs. 2.2% in FGS-, p = 0.042). Frequencies of CD4⁺ cells expressing CCR5 were higher in blood samples from FGS+ than from FGS- women (4.7% vs. 1.5%, p = 0.018). The CD14⁺ cell population decreased significantly in both compartments after anti-schistosomal treatment (p = 0.043). Although the frequency of CD4+ cells did not change after treatment, frequencies of CCR5 expression by CD4+ cells decreased significantly in both compartments (from 3.4% to 0.5% in blood, p = 0.036; and from 42.4% to 5.6% in genital samples, p = 0.025).

Conclusions

The results support the hypothesis that FGS may increase the risk of HIV acquisition, not only through damage of the mucosal epithelial barrier, but also by affecting HIV target cell populations, and that anti-schistosomal treatment can modify this.

Induction of Potent and Long-Lived Antibody and Cellular Immune Responses in the Genitorectal Mucosa Could be the Critical Determinant of HIV Vaccine Efficacy

The field of HIV prevention has indeed progressed in leaps and bounds, but with major limitations of the current prevention and treatment options, the world remains desperate for an HIV vaccine. Sadly, this continues to be elusive, because more than 30 years since its discovery there is no licensed HIV vaccine. Research aiming to define immunological biomarkers to accurately predict vaccine efficacy have focused mainly on systemic immune responses, and as such, studies defining correlates of protection in the genitorectal mucosa, the primary target site for HIV entry and seeding are sparse. Clearly, difficulties in sampling and analysis of mucosal specimens, as well as their limited size have been a major deterrent in characterizing the type (mucosal antibodies, cytokines, chemokines, or CTL), threshold (magnitude, depth, and breadth) and viral inhibitory capacity of HIV-1-specific immune responses in the genitorectal mucosa, where they are needed to immediately block HIV acquisition and arrest subsequent virus dissemination. Nevertheless, a few studies document the existence of HIV-specific immune responses in the genitorectal mucosa of HIV-infected aviremic and viremic controllers, as well as in highly exposed persistently seronegative (HEPS) individuals with natural resistance to HIV-1. Some of these responses strongly correlate with protection from HIV acquisition and/or disease progression, thus providing significant clues of the ideal components of an efficacious HIV vaccine. In this study, we provide an overview of the key features of protective immune responses found in HEPS, elite and viremic controllers, and discuss how these can be achieved through mucosal immunization. Inevitably, HIV vaccine development research will have to consider strategies that elicit potent antibody and cellular immune responses within the genitorectal mucosa or induction of systemic immune cells with an inherent potential to home and persist at mucosal sites of HIV entry.

Impact of asymptomatic herpes simplex virus type 2 infection on mucosal homing and immune cell subsets in the blood and female genital tract

HSV-2 infection is common and generally asymptomatic, but it is associated with increased HIV susceptibility and disease progression. This may relate to herpes-mediated changes in genital and systemic immunology. Cervical cytobrushes and blood were collected from HIV-uninfected African/Caribbean women in Toronto, and immune cell subsets were enumerated blindly by flow cytometry. Immune differences between groups were assessed by univariate analysis and confirmed using a multivariate model. Study participants consisted of 46 women, of whom 54% were infected with HSV-2. T cell activation and expression of the mucosal homing integrin α4β7 (19.60 versus 8.76%; p < 0.001) were increased in the blood of HSV-2-infected women. Furthermore, expression of α4β7 on blood T cells correlated with increased numbers of activated (coexpressing CD38/HLA-DR; p = 0.004) and CCR5(+) (p = 0.005) cervical CD4(+) T cells. HSV-2-infected women exhibited an increase in the number of cervical CD4(+) T cells (715 versus 262 cells/cytobrush; p = 0.016), as well as an increase in the number and proportion of cervical CD4(+) T cells that expressed CCR5(+) (406 versus 131 cells, p = 0.001; and 50.70 versus 34.90%, p = 0.004) and were activated (112 versus 13 cells, p < 0.001; and 9.84 versus 4.86%, p = 0.009). Mannose receptor expression also was increased on cervical dendritic cell subsets. In conclusion, asymptomatic HSV-2 infection was associated with significant systemic and genital immune changes, including increased immune activation and systemic α4β7 expression; correlation of the latter with highly HIV-susceptible CD4(+) T cell subsets in the cervix may provide a mechanism for the increased HIV susceptibility observed in asymptomatic HSV-2-infected women.