The Peptide A-3302-B Isolated from a Marine Bacterium Micromonospora sp. Inhibits HSV-2 Infection by Preventing the Viral Egress from Host Cells.

Herpesviruses are highly prevalent in the human population, and frequent reactivations occur throughout life. Despite antiviral drugs against herpetic infections, the increasing appearance of drug-resistant viral strains and their adverse effects prompt the research of novel antiherpetic drugs for treating lesions. Peptides obtained from natural sources have recently become of particular interest for antiviral therapy applications. In this work, we investigated the antiviral activity of the peptide A-3302-B, isolated from a marine bacterium, Micromonospora sp., strain MAG 9-7, against herpes simplex virus type 1, type 2, and human cytomegalovirus. Results showed that the peptide exerted a specific inhibitory activity against HSV-2 with an EC50 value of 14 µM. Specific antiviral assays were performed to investigate the mechanism of action of A-3302-B. We demonstrated that the peptide did not affect the expression of viral proteins, but it inhibited the late events of the HSV-2 replicative cycle. In detail, it reduced the cell-to-cell virus spread and the transmission of the extracellular free virus by preventing the egress of HSV-2 progeny from the infected cells. The dual antiviral and previously reported anti-inflammatory activities of A-3302-B, and its effect against an acyclovir-resistant HSV-2 strain are attractive features for developing a therapeutic to reduce the transmission of HSV-2 infections.

Human Cytomegalovirus Replication and Infection-Induced Syncytia Formation in Labial, Foreskin, and Fetal Lung Fibroblasts.

Only a handful of cell types, including fibroblasts, epithelial, and endothelial cells, can support human cytomegalovirus (CMV) replication in vitro, in striking contrast to the situation in vivo. While the susceptibility of epithelial and endothelial cells to CMV infection is strongly modulated by their anatomical site of origin, multiple CMV strains have been successfully isolated and propagated on fibroblasts derived from different organs. As oral mucosal cells are likely involved in CMV acquisition, we sought to evaluate the ability of infant labial fibroblasts to support CMV replication, compared to that of commonly used foreskin and fetal lung fibroblasts. No differences were found in the proportion of cells initiating infection, or in the amounts of viral progeny produced after exposure to the fibroblast-adapted CMV strain AD169 or to the endothelial cell-adapted strain TB40/E. Syncytia formation was, however, significantly enhanced in infected labial and lung fibroblasts compared to foreskin-derived cells, and did not occur after infection with AD169. Together, these data indicate that fibroblast populations derived from different tissues are uniformly permissive to CMV infection but retain phenotypic differences of potential importance for infection-induced cell-cell fusion, and ensuing viral spread and pathogenesis in different organs.

Penile intraepithelial neoplasia, penile cancer precursors and human papillomavirus prevalence in symptomatic preputium: a cross-sectional study of 351 circumcised men in Sweden.

OBJECTIVES: To investigate the prevalence of pathological disease and spectrum of human papillomavirus (HPV) types among symptomatic foreskin tissue. PATIENTS AND METHODS: Consecutively excised symptomatic foreskins from 351 men were sent for histopathological evaluation. During the surgical procedure, a fresh biopsy was taken for HPV analysis by modified general primer polymerase chain reaction. A medical questionnaire regarding medication, smoking habits, number of lifetime sexual partners, former diseases and surgery performed on penis was completed by all participants. RESULTS: The most common clinical diagnosis and cause for circumcision was phimosis, seen in 85.2%. Histopathologically inflammatory dermatological conditions were present in 87% of the men. The most common histopathological diagnosis was lichen sclerosus (LS) observed among 58.7%. Notably, penile intraepithelial neoplasia (PeIN) was present in 2% without former clinical suspicion. Overall, HPV was detected in 17.1% of the men and 28 different HPV types were found. High-risk (HR) HPV types were identified in 9.1% and HPV16 was present in 2.3%. Current smoking increased the risk of HPV (crude odds ratio [OR] 2.8, confidence interval [CI] 1.4-5.6; P = 0.005). Having >15 lifetime sexual partners increased the risk of HPV (crude OR 2.6, 95% CI 1.4-5.1; P = 0.003) and when adjusted for current smoking the OR was substantially increased (OR 6.0, 95% CI CI 2.2-16.8; P < 0001). CONCLUSIONS: Histopathological evaluation of circumcised symptomatic foreskin revealed PeIN in 2% of the men without any clinical suspicion of malignancy and that treatable dermatological conditions were present in 87%, LS being the most common. HR-HPV types were present in 9%. Due to risk of malignant development both in PeIN and in inflammatory skin diseases we recommend sending all excised foreskins from patients with symptoms for histopathological evaluation as guidance for further clinical management.

Protocol for a randomized clinical trial exploring the effect of antimicrobial agents on the penile microbiota, immunology and HIV susceptibility of Ugandan men.

BACKGROUND: The foreskin is the main site of HIV acquisition in a heterosexual uncircumcised man, but many men in endemic countries are reluctant to undergo penile circumcision (PC). Observational studies suggest that proinflammatory anaerobic bacteria are enriched on the uncircumcised penis, where they may enhance HIV susceptibility through increased foreskin inflammatory cytokines and the recruitment of HIV-susceptible CD4+ target cells. This trial will examine the impact of systemic and topical antimicrobials on ex vivo foreskin HIV susceptibility. METHODS/DESIGN: This randomized, open-label clinical trial will randomize 125 HIV-negative Ugandan men requesting voluntary PC to one of five arms (n = 25 each). The control group will receive immediate PC, while the four intervention groups will defer PC for 1 month and be provided in the interim with either oral tinidazole, penile topical metronidazole, topical clindamycin, or topical hydrogen peroxide. The impact of these interventions on HIV entry into foreskin-derived CD4+ T cells will be quantified ex vivo at the time of PC using a clade A, R5 tropic HIV pseudovirus assay (primary endpoint); secondary endpoints include the impact of antimicrobials on immune parameters and the microbiota of the participant's penis and of the vagina of their female partner (if applicable), assessed by multiplex enzyme-linked immunosorbent assay and 16S rRNA sequencing. DISCUSSION: There is a critical need to develop acceptable, simple, and effective means of HIV prevention in men unwilling to undergo PC. This trial will provide insight into the causative role of the foreskin microbiota on HIV susceptibility, and the impact of simple microbiota-focused clinical interventions. This may pave the way for future clinical trials using low-cost, nonsurgical intervention(s) to reduce HIV risk in uncircumcised heterosexual men. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03412071 . Retrospectively registered on 26 January 2018.

Tissue-Specific Gene Expression during Productive Human Papillomavirus 16 Infection of Cervical, Foreskin, and Tonsil Epithelium.

Epidemiological data confirm a much higher incidence of high-risk human papillomavirus 16 (HPV16)-mediated carcinogenesis of the cervical epithelium than for other target sites. In order to elucidate tissue-specific responses to virus infection, we compared gene expression changes induced by productive HPV16 infection of cervical, foreskin, and tonsil organotypic rafts. These rafts closely mimic persistent HPV16 infection, long before carcinogenesis sets in. The total number of gene expression changes varied considerably across the tissue types, with only 32 genes being regulated in common. Among them, we confirmed the Kelch-like family protein KLHL35 and the laminin-5 complex to be upregulated and downregulated, respectively, in all the three tissues. HPV16 infection induces upregulation of genes involved in cell cycle control, cell division, mitosis, DNA replication, and DNA damage repair in all the three tissues, indicative of a hyperproliferative environment. In the cervical and tonsil epithelium, we observe significant downregulation of genes involved in epidermis development, keratinocyte differentiation, and extracellular matrix organization. On the other hand, in HPV16-positive foreskin (HPV16 foreskin) tissue, several genes involved in interferon-mediated innate immunity, cytokine signaling, and cellular defenses were downregulated. Furthermore, pathway analysis and experimental validations identified important cellular pathways like STAT1 and transforming growth factor ß (TGF-ß) to be differentially regulated among the three tissue types. The differential modulation of important cellular pathways like TGF-ß1 and STAT1 can explain the sensitivity of tissues to HPV cancer progression.IMPORTANCE Although the high-risk human papillomavirus 16 infects anogenital and oropharyngeal sites, the cervical epithelium has a unique vulnerability to progression of cancer. Host responses during persistent infection and preneoplastic stages can shape the outcome of cancer progression in a tissue-dependent manner. Our study for the first time reports differential regulation of critical cellular functions and signaling pathways during productive HPV16 infection of cervical, foreskin, and tonsil tissues. While the virus induces hyperproliferation in infected cells, it downregulates epithelial differentiation, epidermal development, and innate immune responses, according to the tissue type. Modulation of these biological functions can determine virus fitness and pathogenesis and illuminate key cellular mechanisms that the virus employs to establish persistence and finally initiate disease progression.

Dense Bodies of a gH/gL/UL128/UL130/UL131 Pentamer-Repaired Towne Strain of Human Cytomegalovirus Induce an Enhanced Neutralizing Antibody Response.

The development of a vaccine against human cytomegalovirus infection (HCMV) is a high-priority medical goal. The viral pentameric protein complex consisting of glycoprotein H (gH)/gL/UL128-131A (PC) is considered to be an important vaccine component. Its relevance to the induction of a protective antibody response is, however, still a matter of debate. We addressed this issue by using subviral dense bodies (DBs) of HCMV. DBs are exceptionally immunogenic. Laboratory HCMV strain DBs harbor important neutralizing antibody targets, like the glycoproteins B, H, L, M, and N, but they are devoid of the PC. To be able to directly compare the impact of the PC on the levels of neutralizing antibody (NT-abs) responses, a PC-positive variant of the HCMV laboratory strain Towne was established by bacterial artificial chromosome (BAC) mutagenesis (Towne-UL130rep). This strain synthesized PC-positive DBs upon infection of fibroblasts. These DBs were used in side-by-side immunizations with PC-negative Towne DBs. Mouse and rabbit sera were tested to address the impact of the PC on DB immunogenicity. The neutralizing antibody response to PC-positive DBs was superior to that of PC-negative DBs, as tested on fibroblasts, epithelial cells, and endothelial cells and for both animal species used. The experiments revealed the potential of the PC to enhance the antibody response against HCMV. Of particular interest was the finding that PC-positive DBs induced an antibody response that blocked the infection of fibroblasts by a PC-positive viral strain more efficiently than sera following immunizations with PC-negative particles.IMPORTANCE Infections with the human cytomegalovirus (HCMV) may cause severe and even life-threatening disease manifestations in newborns and immunosuppressed individuals. Several strategies for the development of a vaccine against this virus are currently pursued. A critical question in this respect refers to the antigenic composition of a successful vaccine. Using a subviral particle vaccine candidate, we show here that one protein complex of HCMV, termed the pentameric complex (PC), enhances the neutralizing antibody response against viral infection of different cell types. We further show for the first time that this not only relates to the infection of epithelial or endothelial cells; the presence of the PC in the particles also enhanced the neutralizing antibody response against the infection of fibroblasts by HCMV. Together, these findings argue in favor of including the PC in strategies for HCMV vaccine development.

The Susceptibility of Primary Dermis Fibroblasts from the Chinese Tree Shrew to Human Cytomegalovirus Infection.

As a universal pathogen leading to neonatal defects and transplant failure, human cytomegalovirus (HCMV) has strict species specificity and this has prevented the development of a suitable animal model for the pathogenesis study. The mechanism of cross-species barrier remains elusive and there are so far no non-human cell culture models that support HCMV replication. The Chinese tree shrew (Tupaia belangeri chinensis) is a small laboratory animal and evolutionary closely related with primates. We investigated the susceptibility of primary tree shrew dermis fibroblasts (TSDF) to HCMV infection. Infection with a GFP-expressing HCMV virus resulted in green fluorescence in infected cells with the expression of IE1, UL44 and pp28. The titers of cell-free viruses reached 103 PFU/mL at 96 hpi, compared to titers of 104 PFU/mL observed in primary human foreskin fibroblasts. Our results suggested that TSDF was semi-permissive for HCMV infection. The TSDF model could be further used to investigate key factors influencing cross-species multiplication of HCMV.

Treatment with Radix Euphorbiae Ebracteolatae Significantly Decreases the Expression of E6 and L1, and Increases the Expression of p53 and Rb in HPV18-infected Human Foreskin Keratinocytes.

BACKGROUND: Radix Euphorbiae Ebracteolatae (REE) was recently reported to be significantly superior to vitamin A acid ointment in treating multiple plantar warts. However, the effects of REE on HPV18 remain unclear. Therefore, the current study aimed to investigate the effects of REE on the proliferation of HPV18, and explore possible molecular mechanisms underlying the effects. METHODS: HFK and HFK-HPV18 were treated with water-extracted single or compound REE, ethanol-extracted single or compound REE, TNF-α and IFN for 3 days, respectively. In addition, the organotypic rafts containing HFK-HPV18 and HFK were treated with REE, IFN and TNF-α for 7 days, respectively. Cell proliferation rates were measured with Brdu. mRNA expression of E6, L1, p53 and Rb was detected by qPCR. Protein expression of p53, Rb and L1 was detected by Western blot. RESULTS: Compared to HFK group, HFK-HPV18 group had significantly higher expression of E6 and L1. Compared to the control group, HFK-HPV18 treated with REE, TNF-α and IFN displayed significantly lower proliferation rates. The mRNA expression of E6 was markedly lower, and mRNA expression of p53 and Rb was significantly higher after treatment of REE in HFK-HPV18 or in organotypic rafts containing HFK-HPV18. Treatment with REE markedly increased the protein expression of p53 and Rb, and decreased the protein expression of L1 in HFK-HPV18 or in organotypic rafts containing HFK-HPV18. Among all formula of REE, the inhibition of proliferation rates and expression of E6 and L1, and the increase in expression of p53 and Rb in HFK-HPV18 was highest in ethanol-extracted compound REE group. CONCLUSIONS: The proliferation rates are significantly lower in HFK-HPV18 treated with REE. The expression of E6 and L1 is markedly lower, and expression of p53 and Rb is significantly higher after REE treatment in HFK-HPV18 or organotypic rafts containing HFK-HPV18. Among all formula of REE, ethanol-extracted compound REE displays the highest protection against HPV18.

Oral-genital human papillomavirus infection in Polish couples: frequent detection of HPV 42.

BACKGROUND: Human papillomavirus (HPV) contributes to the development of cervical and oropharyngeal tumors. The increased incidence of HPV associated oropharyngeal tumors is lately being observed also in Polish population. The worldwide distribution of HPV varies and the studies rarely combine analysis of virus genotypes in both: genital and oropharyngeal locations. Therefore, in our study, we investigated HPV distribution in both anatomical sites of females with previous history of cervical cancer or with pre-cancerous lesion and their partners to establish the dominant types in Polish couples in genital and oropharyngeal areas, as they can be easily sexually transmitted. METHODS: The study group consisted of 197 females and their partners. Each female had current or previous cervical pathology and HPV detected in gynecological swab with the use of Anyplex™ II HPV28 Detection system. This system is based on multiplexed real time PCR and enables detection of 19 high-risk and 9 low-risk HPVs. RESULTS: Beside women, the virus was found in 114/197 of men in their foreskin swabs. Additionally, HPV was detected in oropharyngeal swabs of 39/197 female and 56/197 male participants. HPV 16/31/42/39/54 dominated in female and HPV 66/42/16/31/53 in male genital locations. The incidence of HPV in oropharynx was lower, top five genotypes included: HPV 6/39/42/35/16 in women compared to HPV 39/6/42/40/33 in men. HPV16 was the most frequently detected virus type, found in 70/197 examined cervical swabs. It was significantly more prevalent as single infection in females, previously treated for the cervical cancer (p = 0.035). Moreover, regular presence of low risk type 42 was noticeable in both sexes, in both kind of swabs. There was a trend observed towards its prevalence as single infectious agent in women with previous history of cervical cancer (p = 0.069). CONCLUSIONS: Our results showed the distribution of HPV genotypes in Polish couples, in which each woman is HPV positive, indicating a common infection of HPV 42, regardless of sex and anatomical site. These findings shed new light on HPV 42 significance, however they should be verified on a larger group of Polish participants, followed regularly in 6 months intervals, in oral as well as in genital areas.

Orf virus (ORFV) infection in a three-dimensional human skin model: Characteristic cellular alterations and interference with keratinocyte differentiation.

ORF virus (ORFV) is the causative agent of contagious ecthyma, a pustular dermatitis of small ruminants and humans. Even though the development of lesions caused by ORFV was extensively studied in animals, only limited knowledge exists about the lesion development in human skin. The aim of the present study was to evaluate a three-dimensional (3D) organotypic culture (OTC) as a human skin model for ORFV infection considering lesion development, replication of the virus, viral gene transcription and modulation of differentiation of human keratinocytes by ORFV. ORFV infection of OTC was performed using the ORFV isolate B029 derived from a human patient. The OTC sections showed a similar structure of stratified epidermal keratinocytes as human foreskin and a similar expression profile of the differentiation markers keratin 1 (K1), K10, and loricrin. Upon ORFV infection, OTCs exhibited histological cytopathic changes including hyperkeratosis and ballooning degeneration of the keratinocytes. ORFV persisted for 10 days and was located in keratinocytes of the outer epidermal layers. ORFV-specific early, intermediate and late genes were transcribed, but limited viral spread and restricted cell infection were noticed. ORFV infection resulted in downregulation of K1, K10, and loricrin at the transcriptional level without affecting proliferation as shown by PCNA or Ki-67 expression. In conclusion, OTC provides a suitable model to study the interaction of virus with human keratinocytes in a similar structural setting as human skin and reveals that ORFV infection downregulates several differentiation markers in the epidermis of the human skin, a hitherto unknown feature of dermal ORFV infection in man.

Development of disease and immunity at the genital epithelium following intrarectal inoculation of male guinea pigs with herpes simplex virus type 2.

Most analyses of genital immunity to herpes simplex virus type 2 (HSV-2) have been performed in females, consequently immune protection of the male genital epithelium is incompletely understood. We developed a model of male genital HSV-2 infection resulting from intrarectal inoculation of guinea pigs. Vesicular lesions developed transiently on the perineum and foreskin concurrent with acute virus shedding. Virus shedding and recurrent genital lesions were also detected after establishment of a latent infection. Analysis of perineum and foreskin RNA detected transcripts for IFNγ, proinflammatory and regulatory cytokines, and for genes involved in migration and regulation of leukocytes. HSV-specific T cells were detected in lymphoid and genital tissues after resolution of the primary infection whereas virus-specific antibody secreting cells were detected only in lymphoid tissue. Taken together, the ability to quantify pathogenesis and local immunity in this guinea pig model represent an important advance towards understanding immunity to HSV-2 in males.

[HPV infection of the external genitalia in men whose female partners have cervical HPV infection].

OBJECTIVE: Human papilloma virus (HPV) is a necessary cause of cervical cancer and is also closely related to penile cancer, oropharyngeal cancer, and anal cancer in males. However, few studies are reported on male HPV. This study aimed to investigate HPV infection of the external genitalia in men whose female partners have cervical HPV infection. METHODS: We collected the relevant data on the male outpatients whose partners had cervical HPV infection in our Department of Urology and Andrology from August to December 2016. We obtained samples with nylon swabs from the glans penis, corona, inner layer of the prepuce and penile body and detected different types of HPV infection using the Hybribio HPV typing kit, PCR and membrane hybridization. RESULTS: Valid data were collected from 140 males, which showed 83.5% of HPV infection of the external genitalia, including 60 cases of HPV6 (43.2%), 27 cases of HPV16 (19.4%), 14 cases of HPV39 (10.1%), 13 cases of HPV18 (9.4%), 13 cases of HPV58 (9.4%), and 13 cases of HPV52 (9.4%). Redundant prepuce was found in 75.5% of the males, but there was no statistically significant difference in the incidence rate of HPV infection between the normal and redundant prepuce groups (P > 0.05). CONCLUSIONS: Men who have the female partners with positive cervical HPV are at high risk of HPV infection and therefore need to be screened and treated so as to reduce HPV infection in both sexes.

Development of a repeat-exposure penile SHIV infection model in macaques to evaluate biomedical preventions against HIV.

Penile acquisition of HIV infection contributes substantially to the global epidemic. Our goal was to establish a preclinical macaque model of penile HIV infection for evaluating the efficacy of new HIV prevention modalities. Rhesus macaques were challenged once or twice weekly with consistent doses of SHIVsf162P3 (a chimeric simian-human immunodeficiency virus containing HIV env) ranging from 4-600 TCID50 (50% tissue culture infective dose), via two penile routes, until systemic SHIV infection was confirmed. One route exposed the inner foreskin, glans and urethral os to virus following deposition into the prepuce (foreskin) pouch. The second route introduced the virus non-traumatically into the distal urethra only. Single-route challenges resulted in dose-dependent rates of SHIV acquisition informing selection of optimal SHIV dosing. Concurrent SHIV challenges via the prepuce pouch (200 TCID50) and urethra (16 TCID50) resulted in infection of 100% (10/10) animals following a median of 2.5 virus exposures (range, 1-12). We describe the first rhesus macaque repeat-exposure SHIV challenge model of penile HIV acquisition. Utilization of the model should further our understanding of penile HIV infection and facilitate the development of new HIV prevention strategies for men.

HIV internalization into oral and genital epithelial cells by endocytosis and macropinocytosis leads to viral sequestration in the vesicles.

Recently, we showed that HIV-1 is sequestered, i.e., trapped, in the intracellular vesicles of oral and genital epithelial cells. Here, we investigated the mechanisms of HIV-1 sequestration in vesicles of polarized tonsil, foreskin and cervical epithelial cells. HIV-1 internalization into epithelial cells is initiated by multiple entry pathways, including clathrin-, caveolin/lipid raft-associated endocytosis and macropinocytosis. Inhibition of HIV-1 attachment to galactosylceramide and heparan sulfate proteoglycans, and virus endocytosis and macropinocytosis reduced HIV-1 sequestration by 30-40%. T-cell immunoglobulin and mucin domain 1 (TIM-1) were expressed on the apical surface of polarized tonsil, cervical and foreskin epithelial cells. However, TIM-1-associated HIV-1 macropinocytosis and sequestration were detected mostly in tonsil epithelial cells. Sequestered HIV-1 was resistant to trypsin, pronase, and soluble CD4, indicating that the sequestered virus was intracellular. Inhibition of HIV-1 intraepithelial sequestration and elimination of vesicles containing virus in the mucosal epithelium may help in the prevention of HIV-1 mucosal transmission.

The biology of how circumcision reduces HIV susceptibility: broader implications for the prevention field.

Circumcision reduces heterosexual HIV-1 acquisition in men by at least 60%. However, the biological mechanisms by which circumcision is protective remain incompletely understood. We test the hypothesis that the sub-preputial microenvironment created by the foreskin drives immune activation in adjacent foreskin tissues, facilitating HIV-1 infection through a combination of epithelial barrier disruption, enhanced dendritic cell maturation, and the recruitment/activation of neutrophils and susceptible CD4 T cell subsets such as Th17 cells. Furthermore, we provide evidence that the genital microbiome may be an important driver of this immune activation. This suggests that new modalities to reduce genital immune activation and/or alter the genital microbiome, used alone or in combination with topical microbicides, may be of significant benefit to HIV prevention.

HPV prevalence in the foreskins of asymptomatic healthy infants and children: Systematic review and meta-analysis.

The true HPV prevalence in the foreskins of infants and children has been little documented, but reporting on this prevalence is of great importance given its impact on the rationale for treating asymptomatic boys. We searched multiple databases from 1960 to 2016 for observational or prospective studies that reported on HPV prevalence in foreskins. We conducted a meta-analysis using a random-effects model to pool for HPV prevalence in the foreskins of infants and children. Eight studies, with a total of 556 infants and children with phimosis, were eligible for the meta-analysis. The pooled overall prevalence of general HPV, high-risk HPV, low-risk HPV, HPV 16/18, HPV 16, and HPV 18 were 17.3 (95%CI: 0.8-46.3), 12.1 (95% CI: 0.9-31.5), 2.4 (95% CI: 0.0-11.2), 4.8 (95% CI: 0.0-16.8), 1.7 (95% CI: 0.0-5.1), and 0 (95% CI: 0-0.5), respectively. The estimated HPV prevalence in foreskins was not zero among infants and children, which implies HPV transmission other than by sexual contact. Considering that high-risk HPV is detected in asymptomatic infants and children, future studies are warranted to determine whether preventive treatments in asymptomatic infants and children could be effective in preventing persistence or transmission of high-risk HPV.

Penile Anaerobic Dysbiosis as a Risk Factor for HIV Infection.

Sexual transmission of HIV requires exposure to the virus and infection of activated mucosal immune cells, specifically CD4+ T cells or dendritic cells. The foreskin is a major site of viral entry in heterosexual transmission of HIV. Although the probability of acquiring HIV from a sexual encounter is low, the risk varies even after adjusting for known HIV risk factors. The genital microbiome may account for some of the variability in risk by interacting with the host immune system to trigger inflammatory responses that mediate the infection of mucosal immune cells. We conducted a case-control study of uncircumcised participants nested within a randomized-controlled trial of male circumcision in Rakai, Uganda. Using penile (coronal sulcus) swabs collected by study personnel at trial enrollment, we characterized the penile microbiome by sequencing and real-time PCR and cytokine levels by electrochemiluminescence assays. The absolute abundances of penile anaerobes at enrollment were associated with later risk of HIV seroconversion, with a 10-fold increase in Prevotella, Dialister, Finegoldia, and Peptoniphilus increasing the odds of HIV acquisition by 54 to 63%, after controlling for other known HIV risk factors. Increased abundances of anaerobic bacteria were also correlated with increased cytokines, including interleukin-8, which can trigger an inflammatory response that recruits susceptible immune cells, suggesting a mechanism underlying the increased risk. These same anaerobic genera can be shared between heterosexual partners and are associated with increased HIV acquisition in women, pointing to anaerobic dysbiosis in the genital microbiome and an accompanying inflammatory response as a novel, independent, and transmissible risk factor for HIV infection.IMPORTANCE We found that uncircumcised men who became infected by HIV during a 2-year clinical trial had higher levels of penile anaerobes than uncircumcised men who remained HIV negative. We also found that having higher levels of penile anaerobes was also associated with higher production of immune factors that recruit HIV target cells to the foreskin, suggesting that anaerobes may modify HIV risk by triggering inflammation. These anaerobes are known to be shared by heterosexual partners and are associated with HIV risk in women. Therefore, penile anaerobes may be a sexually transmissible risk factor for HIV, and modifying the penile microbiome could potentially reduce HIV acquisition in both men and women.

Foreskin and the molecular politics of risk.

In this paper, I examine disputes over recent claims that male circumcision reduces HIV risk to suggest a complicated relationship between risk individualization and categorization. Whereas randomized controlled trials (RCTs) conducted in sub-Saharan Africa appear to have provided key evidence for the World Health Organization's endorsement of male circumcision as an HIV prevention strategy, RCTs alone did not provide evidence for the underlying causal mechanism. For that, medical authorities have turned to histo-immunological studies of the foreskin's biomolecular vulnerability to HIV, thus molecularizing risk. Some actors used these studies both as a way of shoring up results of RCTs conducted in sub-Saharan Africa and as an important rationale in arguments for making neonatal circumcision more widely available. Others, however, resisted this move to generalize the RCT results to other parts of the world, citing both contextual differences in HIV transmission patterns and conflicting scientific details regarding the biomolecular basis of the foreskin's susceptibility. Nevertheless, by locating an abstract notion of relative risk in the body itself, I argue that histological studies of foreskin have played a key role in stabilizing male circumcision status as a new risk category, largely independent of a given individual's risk profile.

Mucosal stromal fibroblasts markedly enhance HIV infection of CD4+ T cells.

Understanding early events of HIV transmission within mucosal tissues is vital for developing effective prevention strategies. Here, we report that primary stromal fibroblasts isolated from endometrium, cervix, foreskin, male urethra, and intestines significantly increase HIV infection of CD4+ T cells-by up to 37-fold for R5-tropic HIV and 100-fold for X4-tropic HIV-without themselves becoming infected. Fibroblasts were more efficient than dendritic cells at trans-infection and mediate this response in the absence of the DC-SIGN and Siglec-1 receptors. In comparison, mucosal epithelial cells secrete antivirals and inhibit HIV infection. These data suggest that breaches in the epithelium allow external or luminal HIV to escape an antiviral environment to access the infection-favorable environment of the stromal fibroblasts, and suggest that resident fibroblasts have a central, but previously unrecognized, role in HIV acquisition at mucosal sites. Inhibiting fibroblast-mediated enhancement of HIV infection should be considered as a novel prevention strategy.