Semen of HIV-1-infected individuals: local shedding of herpesviruses and reprogrammed cytokine network

Correlation between viral infections in male semen and infertility: a literature review

Infertility affects approximately one-sixth of couples globally, with the incidence of male infertility steadily increasing. However, our understanding of the impact of viral infections on fertility remains limited. This review consolidates findings from previous studies, outlining 40 viruses identified in human semen and summarizing their key characteristics, modes of transmission, and their effects on both the reproductive and endocrine systems. Furthermore, it elucidates potential pathogenic mechanisms and treatment prospects of viruses strongly associated with male infertility. This synthesis will enhance our comprehension of how viral infections influence male reproductive health, offering valuable insights for future research as well as the diagnosis and treatment of infectious infertility.

Update on known and emergent viruses affecting human male genital tract and fertility

Many viruses infect the male genital tract with harmful consequences at individual and population levels. In fact, viral infections may induce damage to different organs of the male genital tract (MGT), therefore compromising male fertility. The oxidative stress, induced during viral-mediated local and systemic inflammation, is responsible for testicular damage, compromising germinal and endocrine cell functions. A reduction in sperm count, motility, number of normal sperm and an increase in DNA fragmentation are all common findings in the course of viral infections that, however, generally regress after infection clearance. In some cases, however, viral shedding persists for a long time leading to unexpected sexual transmission, even after the disappearance of the viral load from the blood.The recent outbreak of Zika and Ebola Virus evidenced how the MGT could represent a reservoir of dangerous emergent viruses and how new modalities of surveillance of survivors are strongly needed to limit viral transmission among the general population.Here we reviewed the evidence concerning the presence of relevant viruses, including emergent and re-emergent, on the male genital tract, their route of entry, their adverse effects on male fertility and the pattern of viral shedding in the semen.We also described laboratory strategies to reduce the risk of horizontal or vertical cross-infection in serodiscordant couples undergoing assisted reproductive technologies.

Cytomegalovirus Infection Facilitates the Costimulation of CD57+CD28- CD8 T Cells in HIV Infection and Atherosclerosis via the CD2-LFA-3 Axis

CD8 T cells are emerging as important mediators in atherosclerosis and cardiovascular disease (CVD). Immune activation may play a particular role in people with HIV (PWH) who are at an increased risk of CVD, even after controlling for known CVD risk factors. Latent CMV infection is associated with increased CVD risk for both PWH and people without HIV, and human CMV-specific CD4 and CD8 T cells are enriched for an immunosenescent phenotype. We previously showed that CMV coinfection in PWH promotes vascular homing and activation of inflammatory CD4 T cells through the CD2-LFA-3 axis. However, the role of CD2/LFA3 costimulation of CD8 T cells in PWH with CMV has yet to be described. In the present study, we demonstrate that CD2 expression on CX3CR1+CD57+CD28- inflammescent CD8 T cells is increased on cells from CMV-seropositive PWH. In vitro CD2/LFA-3 costimulation enhances TCR-mediated activation of these inflammatory CD8 memory T cells. Finally, we show that LFA-3 is highly expressed in aortas of SIV-infected rhesus macaques and in atherosclerotic plaques of people without HIV. Our findings are consistent with a model in which CMV infection enhances CD2 expression on highly proinflammatory CD8 T cells that can then be stimulated by LFA-3 expressed in the vasculature, even in the absence of CD28 costimulation. This model, in which CMV infection exacerbates toxic cytokine and granzyme production by CD8 T cells within the vasculature, highlights a potential therapeutic target in atherosclerosis development and progression, especially for PWH.

A Narrative Review Discussing Vasectomy-Related Impact upon the Status of Oxidative Stress and Inflammation Biomarkers and Semen Microbiota

Background: Male contraceptive approaches besides tubal sterilization involve vasectomy and represent the method of choice among midlife men in developing countries thanks to many advantages. However, the subsidiary consequences of this intervention are insufficiently explored since the involved mechanisms may offer insight into a much more complex picture. Methods: Thus, in this manuscript, we aimed to reunite all available data by searching three separate academic database(s) (PubMed, Web of Knowledge, and Scopus) published in the past two decades by covering the interval 2000–2023 and using a predefined set of keywords and strings involving “oxidative stress” (OS), “inflammation”, and “semen microbiota” in combination with “humans”, “rats”, and “mice”. Results: By following all evidence that fits in the pre-, post-, and vasectomy reversal (VR) stages, we identified a total of n = 210 studies from which only n = 21 were finally included following two procedures of eligibility evaluation. Conclusions: The topic surrounding this intricate landscape has created debate since the current evidence is contradictory, limited, or does not exist. Starting from this consideration, we argue that further research is mandatory to decipher how a vasectomy might disturb homeostasis.

Human seminal plasma stimulates the migration of CD11c+ mononuclear phagocytes to the apical side of the colonic epithelium without altering the junctional complexes in an ex vivo human intestinal model

Introduction

Human immunodeficiency virus type 1 (HIV) transmission mostly occurs through the genital and intestinal mucosae. Although HIV-1 transmission has been extensively investigated, gaps remain in understanding the initial steps of HIV entry through the colonic mucosa. We previously showed that HIV can selectively trigger mononuclear phagocytes (MNP) to migrate within colonic epithelial cells to sample virions. Mucosal exposure to human seminal plasma (HSP), rich in pro- and anti-inflammatory cytokines, chemokines and growth factors, may as well induce alterations of the colonic mucosa and recruit immune cells, hence, affecting pathogen sampling and transmission.

Methods

Here, we studied the role of HSP on the paracellular intestinal permeability by analyzing the distribution of two proteins known to play a key role in controlling the intestinal barrier integrity, namely the tight junctions-associated junctional adhesion molecule (JAM-A) and the adherents junction associated protein E-cadherin (E-CAD), by immunofluorescence and confocal microscopy. Also, we evaluated if HSP promotes the recruitment of MNP cells, specifically, the CD11c and CD64 positive MNPs, to the apical side of the human colonic mucosa. At this scope, HSP of HIV-infected and uninfected individuals with known fertility status was tested for cytokines, chemokines and growth factors concentration and used in an ex vivo polarized colonic tissue culture system to mimic as closely as possible the physiological process.

Results

HSP showed statistically significant differences in cytokines and chemokines concentrations between the three groups of donors, i.e. HIV infected, or uninfected fertile or randomly identified. Nevertheless, we showed that in the ex vivo tissue culture HSP in general, neither affected the morphological structure of the colonic mucosa nor modulated the paracellular intestinal permeability. Interestingly, CD11c+ MNP cells migrated to the apical surface of the colonic epithelium regardless, if incubated with HIV-infected or -uninfected HSPs, while CD64+ MNP cells, did not change their distribution within the colonic mucosa.

Discussion

In conclusion, even if HSP did not perturb the integrity of the human colonic mucosa, it affected the migration of a specific subset of MNPs that express CD11c towards the apical side of the colonic mucosa, which in turn may be involved in pathogen sampling.

Viral tropism for the testis and sexual transmission

The mammalian testis adopts an immune privileged environment to protect male germ cells from adverse autoimmune reaction. The testicular immune privileged status can be also hijacked by various microbial pathogens as a sanctuary to escape systemic immune surveillance. In particular, several viruses have a tropism for the testis. To overcome the immune privileged status and mount an effective local defense against invading viruses, testicular cells are well equipped with innate antiviral machinery. However, several viruses may persist an elongated duration in the testis and disrupt the local immune homeostasis, thereby impairing testicular functions and male fertility. Moreover, the viruses in the testis, as well as other organs of the male reproductive system, can shed to the semen, thus allowing sexual transmission to partners. Viral infection in the testis, which can impair male fertility and lead to sexual transmission, is a serious concern in research on known and on new emerging viruses. To provide references for our scientific peers, this article reviews research achievements and suggests future research focuses in the field.

Human seminal virome: a panel based on recent literature

Background

The seminal virome and its implications for fertility remain poorly understood. To date, there are no defined panels for the detection of viruses of clinical interest in seminal samples.

Results

In this study, we characterized the human seminal virome based on more than 1,000 studies published over the last five years.

Conclusions

The number of studies investigating viruses that occur in human semen has increased, and to date, these studies have been mostly prospective or related to specific clinical findings. Through the joint analysis of all these studies, we have listed the viruses related to the worsening of seminal parameters and propose a new panel with the main viruses already described that possibly affect male fertility and health. This panel can assist in evaluating semen quality and serve as a tool for investigation in cases of infertility.

HIV but Not CMV Replication Alters the Blood Cytokine Network during Early HIV Infection in Men

OBJECTIVE

CMV coinfection contributes to sustained immune activation in people with chronic HIV. In particular, asymptomatic CMV shedding in semen has been associated with increased local and systemic immune activation, even during suppressive antiretroviral therapy (ART). However, the effect of seminal CMV shedding in people with HIV in the earliest phase of HIV infection is not known.

METHODS

Using Luminex, we measured the concentration of 34 cytokines in the blood plasma of sixty-nine men who had sex with men with or without HIV and in subgroups of CMV shedders vs. non-shedders. Differences in blood plasma cytokines between groups were investigated using the multivariate supervised partial least squares discriminant analysis method.

RESULTS

Independently of CMV, we found that concentrations of IP-10, MIG, MCP-1, I-TAC 10, IL-16, and MIP-1β were modulated in the earliest phase of HIV infection compared with control individuals without HIV. In people with HIV, there was no difference in blood cytokines among CMV shedders vs. non-shedders.

CONCLUSION

In early/acute HIV infection, asymptomatic CMV shedding in semen does not drive additional cytokine changes in blood. Early ART initiation should remain the priority, while the added benefit of CMV suppression during the various stages of HIV infection needs to be further investigated.

Effect of HIV suppression on the cytokine network in blood and seminal plasma

OBJECTIVE

HIV infection disrupts the cytokine network and this disruption is not completely reversed by antiretroviral therapy (ART). Characterization of cytokine changes in blood and genital secretions is important for understanding HIV pathogenesis and the mechanisms of HIV sexual transmission. Here, we characterized the cytokine network in individuals longitudinally sampled before they began ART and after achieving suppression of HIV RNA.

METHODS

We measured concentrations of 34 cytokine/chemokines using multiplex bead-based assay in blood and seminal plasma of 19 men with HIV-1 prior to and after viral suppression. We used Partial Least Squares Discriminant Analysis (PLS-DA) to visualize the difference in cytokine pattern between the time points. Any cytokines with VIP scores exceeding 1 were deemed important in predicting suppression status and were subsequently tested using Wilcoxon Signed Rank Tests.

RESULTS

PLS-DA projections in blood were fairly similar before and after viral suppression. In contrast, the difference in PLS-DA projection observed in semen emphasizes that the immunological landscape and immunological needs are very different before and after ART in the male genital compartment. When tested individually, four cytokines were significantly different across time points in semen (MIG, IL-15, IL-7, I-TAC), and two in blood (MIG and IP-10).

CONCLUSION

Viral suppression with ART impacts the inflammatory milieu in seminal plasma. In contrast, the overall effect on the network of cytokines in blood was modest but consistent with prior analyses. These results identify specific changes in the cytokine networks in semen and blood as the immune system acclimates to chronic, suppressed HIV infection.

Viral Infections and Male Infertility: A Comprehensive Review of the Role of Oxidative Stress

Viral infections have been a part of human existence to date, though viruses have posed a huge threat with various outbreaks lately. These threats are associated with reproductive health challenges, especially male infertility. The prime focus of this review is to highlight the mechanisms associated with viral infection-induced male infertility/subfertility and identify new treatment strategies with the aim to preserve male fertility. The reviewed data showed that viral infections stimulate inflammatory responses, resulting in the release of proinflammatory cytokines, which induces oxidative stress. This oxido-inflammatory cycle could continue in a vicious cycle and threaten male fertility. Existing data from human and experimental studies show that viral infection-induced oxido-inflammatory response results in testicular damage, atrophy of the seminiferous tubules and Sertoli cells, and reduced Leydig cell mass. This is accompanied by reduced circulatory testosterone, impaired spermatogenesis, reduced sperm motility, lipid peroxidation, DNA fragmentation and apoptosis of the sperm cells. Based on the available pieces of evidence, antioxidant therapy, in vivo and in vitro, may be beneficial and protects against the potential risk of male infertility from viral infection. It is, however recommended that more clinical studies be conducted to demonstrate the possible protective roles of antioxidants used as adjuvant therapy in viral infections, and in the in vitro treatment of semen samples for those utilizing semen washing and artificial reproductive techniques.

Semen: A modulator of female genital tract inflammation and a vector for HIV-1 transmission

In order to establish productive infection in women, HIV must transverse the vaginal epithelium and gain access to local target cells. Genital inflammation contributes to the availability of HIV susceptible cells at the female genital mucosa and is associated with higher HIV transmission rates in women. Factors that contribute to genital inflammation may subsequently increase the risk of HIV infection in women. Semen is a highly immunomodulatory fluid containing several bioactive molecules with the potential to influence inflammation and immune activation at the female genital tract. In addition to its role as a vector for HIV transmission, semen induces profound mucosal changes to prime the female reproductive tract for conception. Still, most studies of mucosal immunity are conducted in the absence of semen or without considering its immune impact on the female genital tract. This review discusses the various mechanisms by which semen exposure may influence female genital inflammation and highlights the importance of routine screening for semen biomarkers in vaginal specimens to account for its impact on genital inflammation.

The Role of Coinfections in the EBV-Host Broken Equilibrium

The Epstein–Barr virus (EBV) is a well-adapted human virus, and its infection is exclusive to our species, generally beginning in the childhood and then persisting throughout the life of most of the affected adults. Although this infection generally remains asymptomatic, EBV can trigger life-threatening conditions under unclear circumstances. The EBV lifecycle is characterized by interactions with other viruses or bacteria, which increases the probability of awakening its pathobiont capacity. For instance, EBV infects B cells with the potential to alter the germinal center reaction (GCR)—an adaptive immune structure wherein mutagenic-driven processes take place. HIV- and Plasmodium falciparum-induced B cell hyperactivation also feeds the GCR. These agents, along with the B cell tropic KSHV, converge in the ontogeny of germinal center (GC) or post-GC lymphomas. EBV oral transmission facilitates interactions with local bacteria and HPV, thereby increasing the risk of periodontal diseases and head and neck carcinomas. It is less clear as to how EBV is localized in the stomach, but together with Helicobacter pylori, they are known to be responsible for gastric cancer. Perhaps this mechanism is reminiscent of the local inflammation that attracts different herpesviruses and enhances graft damage and chances of rejection in transplanted patients. In this review, we discussed the existing evidence suggestive of EBV possessing the potential to synergize or cooperate with these agents to trigger or worsen the disease.

Dual-targeted anti-CMV/anti-HIV-1 heterodimers

Despite the development of efficient anti-human immunodeficiency virus-1 (HIV-1) therapy, HIV-1 associated pathogens remain a major clinical problem. Human cytomegalovirus (CMV) is among the most common HIV-1 copathogens and one of the main causes of persistent immune activation associated with dysregulation of the immune system, cerebrovascular and cardiovascular pathologies, and premature aging. Here, we report on the development of dual-targeted drugs with activity against both HIV-1 and CMV. We synthesized seven compounds that constitute conjugates of molecules that suppress both pathogens. We showed that all seven compounds exhibit low cytotoxicity and efficiently inhibited both viruses in cell lines. Furthermore, we chose a representative compound and demonstrated that it efficiently suppressed replication of HIV-1 and CMV in human lymphoid tissue ex vivo coinfected with both viruses. Further development of such compounds may lead to the development of dual-targeted anti-CMV/HIV-1 drugs.

Probing the Interface of HIV and Inflammaging

PURPOSE OF REVIEW

Systemic inflammation increases as a consequence of aging (inflammaging) and contributes to age-related morbidities. Inflammation in people living with HIV is elevated compared with the general population even after prolonged suppression of viremia with anti-retroviral therapy. Mechanisms that contribute to inflammation during aging and in treated HIV disease are potentially interactive, leading to an exaggerated inflammatory phenotype in people with HIV.

RECENT FINDINGS

Recent studies highlight roles for anti-retroviral therapy, co-infections, immune system alterations, and microbiome perturbations as important contributors to HIV-associated inflammation. These factors likely contribute to increased risk of age-related morbidities in people living with HIV. Understanding mechanisms that exaggerate the inflammaging process in people with HIV may lead to improved intervention strategies, ultimately, extending both lifespan and healthspan.

Viral infections and implications for male reproductive health

Viral infections have haunted humankind since times immemorial. Overpopulation, globalization, and extensive deforestation have created an ideal environment for a viral spread with unknown and multiple shedding routes. Many viruses can infect the male reproductive tract, with potential adverse consequences to male reproductive health, including infertility and cancer. Moreover, some genital tract viral infections can be sexually transmitted, potentially impacting the resulting offspring's health. We have summarized the evidence concerning the presence and adverse effects of the relevant viruses on the reproductive tract (mumps virus, human immunodeficiency virus, herpes virus, human papillomavirus, hepatitis B and C viruses, Ebola virus, Zika virus, influenza virus, and coronaviruses), their routes of infection, target organs and cells, prevalence and pattern of virus shedding in semen, as well as diagnosis/testing and treatment strategies. The pathophysiological understanding in the male genital tract is essential to assess its clinical impact on male reproductive health and guide future research.

Cytokine Network and Sexual Human Immunodeficiency Virus Transmission in Men Who Have Sex With Men

BACKGROUND

Seminal human immunodeficiency virus (HIV) transmission from men to their partners remains the main driver of HIV epidemics worldwide. Semen is not merely a carrier of the virus, but also provides an immunological milieu that affects HIV transmission.

METHODS

We collected blood and semen from people with HIV whose epidemiologically linked sexual partners either did or did not acquire HIV. Viral transmission was confirmed by phylogenetic linkage (HIV pol). We measured the concentration of 34 cytokines/chemokines by Luminex in the blood and semen of 21 source partners who transmitted HIV (transmitters) and 22 who did not transmit HIV (nontransmitters) to their sexual partners. Differences between cytokine profiles in transmitters versus nontransmitters were analyzed using the multivariate statistical technique of partial least square discriminant analysis.

RESULTS

The cytokine profile in seminal fluid, but not in peripheral blood, was significantly different between men who have sex with men (MSM) who transmitted HIV and those who did not transmit HIV to their sexual partners (E = 19.77; P < .01). This difference persisted after excluding people with undetectable HIV RNA levels in nontransmitters.

CONCLUSIONS

Seminal cytokine profiles correlated with transmission or nontransmission of HIV from the infected MSM to their partners, independently from seminal viral load. Seminal cytokine spectra might be a contributing determinant of sexual HIV transmission, thus providing new directions for the development of strategies aimed at preventing HIV transmission.

High abundance of human herpesvirus 8 in wastewater from a large urban area

AIMS

This study assesses the diversity and abundance of Human Herpesviruses (HHVs) in the influent of an urban wastewater treatment plant using shotgun sequencing, metagenomic analysis and qPCR.

METHODS AND RESULTS

Influent wastewater samples were collected from the three interceptors that serve the City of Detroit and Wayne, Macomb and Oakland counties between November 2017 to February 2018. The samples were subjected to a series of processes to concentrate viruses which were further sequenced and amplified using qPCR. All nine types of HHV were detected in wastewater. Human Herpesvirus 8 (HHV-8), known as Kaposi's sarcoma herpesvirus, which is only prevalent in 5-10% of USA population, was found to be the most abundant followed by HHV-3 or Varicella-zoster virus.

CONCLUSIONS

The high abundance of HHV-8 in the Detroit metropolitan area may be attributed to the HIV-AIDS outbreak that was ongoing in Detroit during the sampling period.

SIGNIFICANCE AND IMPACT OF THE STUDY

The approach described in this paper can be used to establish a baseline of viruses secreted by the community as a whole. Sudden changes in the baseline would identify changes in community health and immunity.

Seminal Plasma-Derived Extracellular-Vesicle Fractions from HIV-Infected Men Exhibit Unique MicroRNA Signatures and Induce a Proinflammatory Response in Cells Isolated from the Female Reproductive Tract

The continuing spread of HIV/AIDS is predominantly fueled by sexual exposure to HIV-contaminated semen. Seminal plasma (SP), the liquid portion of semen, harbors a variety of factors that may favor HIV transmission by facilitating viral entry into host cells, eliciting the production of proinflammatory cytokines, and enhancing the translocation of HIV across the genital epithelium. One important and abundant class of factors in SP is extracellular vesicles (EVs), which, in general, are important intercellular signal transducers. Although numerous studies have characterized blood plasma-derived EVs from both uninfected and HIV-infected individuals, little is known about the properties of EVs from the semen of HIV-infected individuals. We report here that fractionated SP enriched for EVs from HIV-infected men induces potent transcriptional responses in epithelial and stromal cells that interface with the luminal contents of the female reproductive tract. Semen EV fractions from acutely infected individuals induced a more proinflammatory signature than those from uninfected individuals. This was not associated with any observable differences in the surface phenotypes of the vesicles. However, microRNA (miRNA) expression profiling analysis revealed that EV fractions from infected individuals exhibit a broader and more diverse profile than those from uninfected individuals. Taken together, our data suggest that SP EVs from HIV-infected individuals exhibit unique miRNA signatures and exert potent proinflammatory transcriptional changes in cells of the female reproductive tract, which may facilitate HIV transmission.IMPORTANCE Seminal plasma (SP), the major vehicle for HIV, can modulate HIV transmission risk through a variety of mechanisms. Extracellular vesicles (EVs) are extremely abundant in semen, and because they play a key role in intercellular communication pathways and immune regulation, they may impact the likelihood of HIV transmission. However, little is known about the properties and signaling effects of SP-derived EVs in the context of HIV transmission. Here, we conduct a phenotypic, transcriptomic, and functional characterization of SP and SP-derived EVs from uninfected and HIV-infected men. We find that both SP and its associated EVs elicit potent proinflammatory transcriptional responses in cells that line the genital tract. EVs from HIV-infected men exhibit a more diverse repertoire of miRNAs than EVs from uninfected men. Our findings suggest that EVs from the semen of HIV-infected men may significantly impact the likelihood of HIV transmission through multiple mechanisms.

Deep Sequencing Reveals Compartmentalized HIV-1 in the Semen of Men with and without Sexually Transmitted Infection-Associated Urethritis

Concurrent sexually transmitted infections (STI) can increase the probability of HIV-1 transmission primarily by increasing the viral load present in semen. In this study, we explored the relationship of HIV-1 in blood and seminal plasma in the presence and absence of urethritis and after treatment of the concurrent STI. Primer ID deep sequencing of the V1/V3 region of the HIV-1 env gene was done for paired blood and semen samples from antiretroviral therapy (ART)-naive men living in Malawi with (n = 19) and without (n = 5) STI-associated urethritis; for a subset of samples, full-length env genes were generated for sequence analysis and to test entry phenotype. Cytokine concentrations in the blood and semen were also measured, and a reduction in the levels of proinflammatory cytokines was observed following STI treatment. We observed no difference in the prevalence of diverse compartmentalized semen-derived lineages in men with or without STI-associated urethritis, and these viral populations were largely stable during STI treatment. Clonal amplification of one or a few viral sequences accounted for nearly 50% of the viral population, indicating a recent bottleneck followed by limited viral replication. We conclude that the male genital tract is a site where virus can be brought in from the blood, where localized sustained replication can occur, and where specific genotypes can be amplified, perhaps initially by cellular proliferation but further by limited viral replication.IMPORTANCE HIV-1 infection is a sexually transmitted infection that coexists with other STI. Here, we examined the impact of a concurrent STI resulting in urethritis on the HIV-1 population within the male genital tract. We found that viral populations remain largely stable even with treatment of the STI. These results show that viral populations within the male genital tract are defined by factors beyond transient inflammation associated with a concurrent STI.

Shedding Light on the Role of Extracellular Vesicles in HIV Infection and Wound Healing

Extracellular vesicles (EVs) play an important role in intercellular communication. They are naturally released from cells into the extracellular environment. Based on their biogenesis, release pathways, size, content, and function, EVs are classified into exosomes, microvesicles (MVs), and apoptotic bodies (ApoBDs). Previous research has documented that EVs, specifically exosomes and MVs, play an important role in HIV infection, either by promoting HIV infection and pathogenesis or by inhibiting HIV-1 to a certain extent. We have also previously reported that EVs (particularly exosomes) from vaginal fluids inhibit HIV at the post-entry step (i.e., reverse transcription, integration). Besides the role that EVs play in HIV, they are also known to regulate the process of wound healing by regulating both the immune and inflammatory responses. It is noted that during the advanced stages of HIV infection, patients are at greater risk of wound-healing and wound-related complications. Despite ongoing research, the data on the actual effects of EVs in HIV infection and wound healing are still premature. This review aimed to update the current knowledge about the roles of EVs in regulating HIV pathogenesis and wound healing. Additionally, we highlighted several avenues of EV involvement in the process of wound healing, including coagulation, inflammation, proliferation, and extracellular matrix remodeling. Understanding the role of EVs in HIV infection and wound healing could significantly contribute to the development of new and potent antiviral therapeutic strategies and approaches to resolve impaired wounds in HIV patients.

From Ancient to Emerging Infections: The Odyssey of Viruses in the Male Genital Tract

The male genital tract (MGT) is the target of a number of viral infections that can have deleterious consequences at the individual, offspring, and population levels. These consequences include infertility, cancers of male organs, transmission to the embryo/fetal development abnormalities, and sexual dissemination of major viral pathogens such as human immunodeficiency virus (HIV) and hepatitis B virus. Lately, two emerging viruses, Zika and Ebola, have additionally revealed that the human MGT can constitute a reservoir for viruses cleared from peripheral circulation by the immune system, leading to their sexual transmission by cured men. This represents a concern for future epidemics and further underlines the need for a better understanding of the interplay between viruses and the MGT. We review here how viruses, from ancient viruses that integrated the germline during evolution through old viruses (e.g., papillomaviruses originating from Neanderthals) and more modern sexually transmitted infections (e.g., simian zoonotic HIV) to emerging viruses (e.g., Ebola and Zika) take advantage of genital tract colonization for horizontal dissemination, viral persistence, vertical transmission, and endogenization. The MGT immune responses to viruses and the impact of these infections are discussed. We summarize the latest data regarding the sources of viruses in semen and the complex role of this body fluid in sexual transmission. Finally, we introduce key animal findings that are relevant for our understanding of viral infection and persistence in the human MGT and suggest future research directions.

Subclinical Cytomegalovirus DNA Is Associated with CD4 T Cell Activation and Impaired CD8 T Cell CD107a Expression in People Living with HIV despite Early Antiretroviral Therapy

Most people living with HIV (PLWH) are coinfected with cytomegalovirus (CMV). Subclinical CMV replication is associated with immune dysfunction and with increased HIV DNA in antiretroviral therapy (ART)-naive and -suppressed PLWH. To identify immunological mechanisms by which CMV could favor HIV persistence, we analyzed 181 peripheral blood mononuclear cell (PBMC) samples from 64 PLWH starting ART during early HIV infection with subsequent virologic suppression up to 58 months. In each sample, we measured levels of CMV and Epstein-Barr virus (EBV) DNA by droplet digital PCR (ddPCR). We also measured expression of immunological markers for activation (HLA-DR+ CD38+), cycling (Ki-67+), degranulation (CD107a+), and the immune checkpoint protein PD-1 on CD4+ and CD8+ T cell memory subsets. Significant differences in percentages of lymphocyte markers by CMV/EBV shedding were identified using generalized linear mixed-effects models. Overall, CMV DNA was detected at 60/181 time points. At the time of ART initiation, the presence of detectable CMV DNA was associated with increased CD4+ T cell activation and CD107a expression and with increased CD8+ T cellular cycling and reduced CD107a expression on CD8+ T cells. While some effects disappeared during ART, greater CD4+ T cell activation and reduced CD107a expression on CD8+ T cells persisted when CMV was present (P < 0.01). In contrast, EBV was not associated with any immunological differences. Among the covariates, peak HIV RNA and CD4/CD8 ratio had the most significant effect on the immune system. In conclusion, our study identified immune differences in PLWH with detectable CMV starting early ART, which may represent an additional hurdle for HIV cure efforts.IMPORTANCE Chronic viral infections such as with HIV and CMV last a lifetime and can continually antagonize the immune system. Both viruses are associated with higher expression of inflammation markers, and recent evidence suggests that CMV may complicate efforts to deplete HIV reservoirs. Our group and others have shown that CMV shedding is associated with a larger HIV reservoir. Subclinical CMV replication could favor HIV persistence via bystander effects on our immune system. In this study, we collected longitudinal PBMC samples from people starting ART and measured immune changes associated with detectable CMV. We found that when CMV was detectable, CD4+ T cell activation was higher and CD8+ T cell degranulation was lower. Both results may contribute to the slower decay of the size of the reservoir during CMV replication, since activated CD4+ T cells are more vulnerable to HIV infection, while the loss of CD8+ T cell degranulation may impede the proper killing of infected cells.

Vehicles of intercellular communication: exosomes and HIV-1

The terms extracellular vesicles, microvesicles, oncosomes, or exosomes are often used interchangeably as descriptors of particles that are released from cells and comprise a lipid membrane that encapsulates nucleic acids and proteins. Although these entities are defined based on a specific size range and/or mechanism of release, the terminology is often ambiguous. Nevertheless, these vesicles are increasingly recognized as important modulators of intercellular communication. The generic characterization of extracellular vesicles could also be used as a descriptor of enveloped viruses, highlighting the fact that extracellular vesicles and enveloped viruses are similar in both composition and function. Their high degree of similarity makes differentiating between vesicles and enveloped viruses in biological specimens particularly difficult. Because viral particles and extracellular vesicles are produced simultaneously in infected cells, it is necessary to separate these populations to understand their independent functions. We summarize current understanding of the similarities and differences of extracellular vesicles, which henceforth we will refer to as exosomes, and the enveloped retrovirus, HIV-1. Here, we focus on the presence of these particles in semen, as these are of particular importance during HIV-1 sexual transmission. While there is overlap in the terminology and physical qualities between HIV-1 virions and exosomes, these two types of intercellular vehicles may differ depending on the bio-fluid source. Recent data have demonstrated that exosomes from human semen serve as regulators of HIV-1 infection that may contribute to the remarkably low risk of infection per sexual exposure.

IP-10 is highly involved in HIV infection

Interferon-γ (IFN-γ)-induced protein 10 (IP-10 or CXCL-10) is a chemokine involved in trafficking immune cells to inflammatory sites. Numerous studies have reported abnormally high plasma IP-10 levels in the context of human immunodeficiency virus (HIV) infection, and IP-10 is considered an important pro-inflammatory factor in the HIV disease process. The data regarding the roles of IP-10 in HIV infection required collation; this review summarizes the biological characteristics of IP-10, the positive association between plasma IP-10 levels and HIV disease progression, the effect of IP-10 on human immune cells, and potential related mechanisms. This review provides important insights into the role of IP-10 in HIV monitoring and treatment.

Persistence and Intra-Host Genetic Evolution of Zika Virus Infection in Symptomatic Adults: A Special View in the Male Reproductive System

We followed the presence of Zika virus (ZIKV) in four healthy adults (two men and two women), for periods ranging from 78 to 298 days post symptom onset. The patients were evaluated regarding the presence of the virus in different body fluids (blood, saliva, urine and semen), development of immune responses (including antibodies, cytokines and chemokines), and virus genetic variation within samples collected from semen and urine during the infection course. The analysis was focused primarily on the two male patients who shed the virus for up to 158 days after the initial symptoms. ZIKV particles were detected in the spermatozoa cytoplasm and flagella, in immature sperm cells and could also be isolated from semen in cell culture, confirming that the virus is able to preserve integrity and infectivity during replication in the male reproductive system (MRS). Despite the damage caused by ZIKV infection within the MRS, our data showed that ZIKV infection did not result in infertility at least in one of the male patients. This patient was able to conceive a child after the infection. We also detected alterations in the male genital cytokine milieu, which could play an important role in the replication and transmission of the virus which could considerably increase the risk of ZIKV sexual spread. In addition, full genome ZIKV sequences were obtained from several samples (mainly semen), which allowed us to monitor the evolution of the virus within a patient during the infection course. We observed genetic changes over time in consensus sequences and lower frequency intra-host single nucleotide variants (iSNV), that suggested independent compartmentalization of ZIKV populations in the reproductive and urinary systems. Altogether, the present observations confirm the risks associated with the long-term replication and shedding of ZIKV in the MRS and help to elucidate patterns of intra-host genetic evolution during long term replication of the virus.

Seroprevalence of HSV-1 and 2 in HIV-infected males with and without GUD: Study from a tertiary care setting of India

BACKGROUND

Herpes simplex virus (HSV) infection is associated with an increased risk of both human immune deficiency virus (HIV) transmission and acquisition. However, in India, literature on HSV infections in in HIV-infected males has been scarce. The present study was carried out to assess the seroprevalence of these viruses in HIV-infected males, so as to provide a baseline data from India and report on HSV associated GUD prevalence in HIV infected males.

OBJECTIVE

The aim of the study was to estimate the seroprevalence of herpes simplex type 1 and 2 viruses in HIV-infected males with and without genital ulcers disease (GUD).

MATERIAL AND METHODS

It was a prospective study. We included a total of 351 male participants in this study. Among these 233 were HIV-infected and 118 HIV-uninfected males who served as controls. The seroprevalence was estimated, using HSV-1 and 2 type specific IgG and IgM antibodies by ELISA.

RESULTS

HIV-infected patients had a median age of 32 ± 6.97 years (interquartile range: 28-36). Of the 351 males, 25.92% (91/351) were infected with HSV-1 and HSV-2 both. The overall seroprevalence of HSV-1 singly infected, HSV-2 singly infected, and dual infection in HIV-infected males was 39.92%, 25.58%, and 37.33% whereas in HIV-uninfected group the corresponding figures were 71.18%, 5.08%, and 3.38%, respectively. Seven of 233 (3%) HIV-infected males were having incident HSV infection. GUD was reported in both HSV-1 and HSV-2 seropositive individuals.

CONCLUSIONS

Both HSV-1 and HSV-2 infections were found to be associated with GUD in HIV-infected patients. The prevalence of HIV-HSV co-infection among GUD patients is high.

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

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

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

Vagal dysfunction and small intestinal bacterial overgrowth: novel pathways to chronic inflammation in HIV

OBJECTIVE

Chronic inflammation in HIV-infected individuals drives disease progression and the development of comorbidities, despite viral suppression with combined antiretroviral therapy. Here, we sought evidence that vagal dysfunction, which occurs commonly as part of HIV-associated autonomic neuropathy, could exacerbate inflammation through gastrointestinal dysmotility, small intestinal bacterial overgrowth (SIBO), and alterations in patterns of soluble immune mediators.

DESIGN

This is a cross-sectional observational study.

METHODS

Forty participants on stable combined antiretroviral therapy with gastrointestinal symptoms, and no causes for vagal or gastrointestinal dysfunction other than HIV, underwent autonomic testing, hydrogen/methane breath testing for SIBO, and gastric emptying scintigraphy. A panel of 41 cytokines, high-mobility group box 1, and markers of bacterial translocation (lipopolysaccharide) and monocyte/macrophage activation (sCD14 and sCD163) were tested in plasma.

RESULTS

We found that participants with vagal dysfunction had delayed gastric emptying and higher prevalence of SIBO. SIBO was associated with IL-6, but not sCD14; lipopolysaccharide could not be detected in any participant. We also found alteration of cytokine networks in participants with vagal dysfunction, with stronger and more numerous positive correlations between cytokines. In the vagal dysfunction group, high mobility group box 1 was the only soluble mediator displaying strong negative correlations with other cytokines, especially those cytokines that had numerous other strong positive correlations.

CONCLUSION

The current study provides evidence that the vagal component of HIV-associated autonomic neuropathy is associated with changes in immune and gastrointestinal function in individuals with well treated HIV. Further study will be needed to understand whether therapies targeted at enhancing vagal function could be of benefit in HIV.

Subclinical herpesvirus shedding among HIV-1-infected men on antiretroviral therapy

OBJECTIVE

We evaluated the subclinical shedding of six different herpesviruses in antiretroviral drug-treated HIV-positive [HIV(+)] MSM, and determined how this is associated with markers of inflammation and immune activation.

METHODS

We obtained blood, semen, throat washing, urine, and stool from 15 antiretroviral-treated HIV-1-infected MSM with CD4 T-cell reconstitution, and 12 age-matched HIV-negative [HIV (-)] MSM from the Multicenter AIDS Cohort Study at four timepoints over 24 weeks to measure DNA levels of cytomegalovirus (CMV), Epstein-Barr virus (EBV), herpes simplex virus 1 and 2, human herpesvirus 6 (HHV6), and HHV8. T-cell activation and plasma levels of soluble markers of inflammation and activation were also measured at the corresponding timepoints.

RESULTS

HIV(+) participants had a trend for higher total herpesvirus shedding rate. HIV(+) participants also had a significantly higher rate of shedding EBV and CMV compared with the HIV(-) group. Herpesvirus shedding was mostly seen in throat washings. In the HIV(+) group, herpesvirus shedding rate inversely correlated with plasma levels of interferon γ-induced protein 10 and soluble CD163. CMV DNA levels negatively correlated with levels of T-cell activation. There was a trend for a positive correlation between EBV shedding rate and plasma soluble CD14. HHV6 shedding rate negatively correlated with plasma levels of interleukin-6, soluble CD163, and interferon gamma-induced protein 10. Correlations were not observed among HIV(-) individuals.

CONCLUSION

Among treated HIV-infected MSM, there are higher subclinical shedding rates of some herpesviruses that occur in different body compartments and negatively correlate with levels of inflammation and immune activation.

A common anti-cytomegalovirus drug, ganciclovir, inhibits HIV-1 replication in human tissues ex vivo

BACKGROUND

Cytomegalovirus (CMV) is a common HIV-1 copathogen. Since CMV infection is an important contributor to immune activation, the driving force of HIV disease, an anti-CMV strategy might be beneficial to HIV-infected patients. Shin et al. (J Acquir Immune Defic Syndr 2014; 65:251-258) reported that anti-CMV therapy with valganciclovir in coinfected individuals results in a decrease of HIV viral load that is not accompanied by a decrease of immune activation. This suggests an alternative mechanism for HIV inhibition other than suppression of CMV-mediated inflammation.

METHOD

We evaluated the anti-HIV activity of ganciclovir (GCV), the active form of valganciclovir, on HIV replication in human tissues ex vivo.

RESULTS

We show that GCV has a direct suppressive activity on HIV replication in human tissues ex vivo, including laboratory strains, drug-resistant and primate HIV-1 isolates. We deciphered the mechanism of this inhibition and showed that GCV-TP is incorporated in the nascent DNA chain and acts as a delayed chain terminator.

CONCLUSION

Our results suggest that anti-CMV strategy using valganciclovir in HIV-1-infected individuals may reduce HIV-1 viral load not only indirectly by decreasing CMV-mediated immune activation but also directly by inhibiting HIV-1 reverse transcriptase.

Impact of early cART on HIV blood and semen compartments at the time of primary infection

BACKGROUND

HIV-infected cells in semen facilitate viral transmission. We studied the establishment of HIV reservoirs in semen and blood during PHI, along with systemic immune activation and the impact of early cART.

METHODS

Patients in the ANRS-147-OPTIPRIM trial received two years of early cART. Nineteen patients of the trial were analyzed, out of which 8 had acute PHI (WB ≤1 Ab). We quantified total cell-associated (ca) HIV-DNA in blood and semen and HIV-RNA in blood and semen plasma samples, collected during PHI and at 24 months of treatment.

RESULTS

At enrollment, HIV-RNA load was higher in blood than in semen (median 5.66 vs 4.22 log10 cp/mL, p<0.0001). Semen HIV-RNA load correlated strongly with blood HIV-RNA load (r = 0.81, p = 0.02, the CD4 cell count (r = -0.98, p<0.0001), and the CD4/CD8 ratio (r = -0.85, p<0.01) in acute infection but not in later stages of PHI. Median blood and seminal cellular HIV-DNA levels were 3.59 and 0.31 log10cp/106 cells, respectively. HIV-DNA load peaked in semen later than in blood and then correlated with blood IP10 level (r = 0.62, p = 0.04). HIV-RNA was undetectable in blood and semen after two years of effective cART. Semen HIV-DNA load declined similarly, except in one patient who had persistently high IP-10 and IL-6 levels and used recreational drugs.

CONCLUSIONS

HIV reservoir cells are found in semen during PHI, with gradual compartmentalization. Its size was linked to the plasma IP-10 level. Early treatment purges both the virus and infected cells, reducing the high risk of transmission during PHI.

CLINICAL TRIALS REGISTRATION

NCT01033760.

HIV Trafficking Between Blood and Semen During Early Untreated HIV Infection

BACKGROUND

Understanding the dynamics of HIV across anatomic compartments is important to design effective eradication strategies. In this study, we evaluated viral trafficking between blood and semen during primary HIV infection in 6 antiretroviral-naive men who have sex with men.

METHODS

Deep sequencing data of HIV env were generated from longitudinal blood plasma, peripheral blood mononuclear cells, and seminal plasma samples. The presence or absence of viral compartmentalization was assessed using tree-based Slatkin-Maddison and distance-based Fst methods. Phylogeographic analyses were performed using a discrete Bayesian asymmetric approach of diffusion with Markov jump count estimation to evaluate the gene flow between blood and semen during primary HIV infection. Levels of DNA from human herpesviruses and selected inflammatory cytokines were also measured on genital secretions collected at baseline to evaluate potential correlates of increased viral migration between anatomic compartments.

RESULTS

We detected varying degrees of compartmentalization in all 6 individuals evaluated. None of them maintained viral compartmentalization between blood and seminal plasma throughout the analyzed time points. Phylogeographic analyses revealed that the HIV population circulating in blood plasma populated the seminal compartment during the earliest stages of infection. In our limited data set, we found no association between local inflammation or herpesvirus shedding at baseline and viral trafficking between semen and blood.

CONCLUSIONS

The early spread of virus from blood plasma to genital tract and the complex viral interplay between these compartments suggest that viral eradication efforts will require monitoring viral subpopulations in anatomic sites and viral trafficking during the course of infection.

Clinical and Mucosal Immune Correlates of HIV-1 Semen Levels in Antiretroviral-Naive Men

Background

This study was done to characterize parameters associated with semen human immunodeficiency virus (HIV)-1 ribonucleic acid (RNA) viral load (VL) variability in HIV-infected, therapy-naive men.

Methods

Paired blood and semen samples were collected from 30 HIV-infected, therapy-naive men who have sex with men, and 13 participants were observed longitudinally for up to 1 year. Human immunodeficiency virus RNA, bacterial load by 16S RNA, herpesvirus (Epstein-Barr virus and cytomegalovirus [CMV]) shedding, and semen cytokines/chemokines were quantified, and semen T-cell subsets were assessed by multiparameter flow cytometry.

Results

Semen HIV RNA was detected at 93% of visits, with >50% of men shedding high levels of virus (defined as >5000 copies/mL). In the baseline cross-sectional analysis, an increased semen HIV VL correlated with local CMV reactivation, the semen bacterial load, and semen inflammatory cytokines, particularly interleukin (IL)-8. T cells in semen were more activated than blood, and there was an increased frequency of Th17 cells and γδ-T-cells. Subsequent prospective analysis demonstrated striking interindividual variability in HIV and CMV shedding patterns, and only semen IL-8 levels and the blood VL were independently associated with semen HIV levels.

Conclusions

Several clinical and immune parameters were associated with increased HIV semen levels in antiretroviral therapy-naive men, with induction of local proinflammatory cytokines potentially acting as a common pathway.

Longitudinal Viral Dynamics in Semen During Early HIV Infection

Background

Multiple viruses coinfect the male genital tract, influencing each other’s replication and perhaps affecting human immunodeficiency virus (HIV) pathogenesis and disease progression.

Methods

This study included 453 longitudinal seminal samples from 195 HIV-infected men from the San Diego Primary Infection Resource Consortium and 67 seminal samples from HIV-negative healthy controls. Seminal HIV RNA and DNA from 7 human herpesviruses (HHVs) were measured by real-time polymerase chain reaction. Longitudinal shedding rates were determined by Kaplan-Meier survival analysis. Predictors of viral shedding were determined using backwards selection in a multivariable generalized estimating equation model.

Results

HIV-infected participants presented significantly increased rates of seminal HHV shedding compared with HIV-uninfected controls. Cytomegalovirus (CMV) and Epstein-Barr virus (EBV) were the most commonly detected HHV in semen of HIV-infected participants. Persistent shedding was more common for CMV and EBV when compared to other HHVs. With exception of HHV-7, HHV shedding was not significantly influenced by HIV RNA levels, CD4+ cell counts, or antiretroviral therapy. Presence of CMV, EBV, and herpes simplex virus (HSV) were independent predictors of genital HIV RNA shedding after adjusting for plasma HIV RNA and longitudinal measurements.

Conclusions

Seminal replication of multiple HHVs is common in our HIV primary infection cohort. Genital replication of CMV and EBV was the most common and was significantly associated with seminal HIV RNA shedding. Prevalence of HSV shedding was lower and mostly intermittent, but its association with seminal HIV RNA was the strongest. Understanding the complex viral milieu in semen is important for HIV transmission but might also play a role in HIV pathogenesis and disease progression.

Partners in Crime: The Role of CMV in Immune Dysregulation and Clinical Outcome During HIV Infection

In the current era of combination antiretroviral therapy (ART), human immunodeficiency virus (HIV)-infected individuals are living longer and healthier lives. Nevertheless, HIV-infected persons are at greater risk for age-related disorders, which have been linked to residual immune dysfunction and inflammation. HIV-infected individuals are almost universally co-infected with cytomegalovirus (CMV) and both viruses are associated with inflammation-related morbidities. Therefore, a detailed investigation of the relationship between CMV and aging-related morbidities emerging during chronic HIV infection is warranted. Here, we review the literature on how CMV co-infection affects HIV infection and host immunity and we discuss the gaps in our knowledge that need elucidation.

Review of cytomegalovirus coinfection in HIV-infected individuals in Africa

BACKGROUND

Cytomegalovirus (CMV) infection among HIV-infected individuals may cause end-organ disease, which is an AIDS-defining condition. Evidence from high-income countries suggests that CMV may alter the outcome of HIV infection, other than causing end-organ diseases. We reviewed literature on HIV and CMV coinfection in Africa.

METHODS

Systematic review of published studies on HIV and CMV coinfection in Africa using the PubMed database.

RESULTS

High CMV seroprevalence was found throughout Africa, exceeding 90% in most populations. Retinitis, pneumonia, and colitis were the most commonly reported CMV manifestations in HIV-infected individuals. Among patients with pulmonary symptoms, the prevalence of CMV pneumonitis varied from 20% to over 60%, whereas CMV was found in 0% to 14% of patients with gastrointestinal manifestations. Cytomegalovirus retinitis was found in 0% to 2.6% of examined HIV-infected individuals. The diagnostics of CMV end-organ diseases were found complex and difficult to interpret in African settings. Cytomegalovirus viremia was correlated with significantly lower CD4 cell count and increase in activated and apoptosis vulnerable T-lymphocytes. Also, CMV coinfection was found to be associated with increased transmission and progression of HIV infection. Moreover, detectable CMV DNA was an independent predictor of HIV transmission and mortality among HIV-infected individuals.

CONCLUSIONS

Cytomegalovirus is highly prevalent in Africa and a common cause of disease manifestations in HIV-infected individuals among all age groups. Cytomegalovirus coinfection in HIV-infected individuals in Africa is associated with increased transmission and mortality of HIV, but it is a neglected area of research.

Comparison of the effect of semen from HIV-infected and uninfected men on CD4+ T-cell infection

Objectives:

Semen composition is influenced by HIV-1 infection, yet the impact of semen components on HIV infection of primary target cells has only been studied in samples from HIV-uninfected donors.

Design:

We compared the effect of seminal plasma (SP) from chronically HIV-infected (SP+) versus uninfected donors (SP–) on HIV-1 infection of peripheral blood mononuclear cells (PBMCs) and CD4⁺ T cells.

Methods:

Primary cells were infected with HIV-1 in the presence of SP+ or SP– and analyzed for infection level, metabolic activity, HIV receptor expression, proliferation and activation. SP+ and SP– were compared for infection-enhancing peptides, cytokines and prostaglandin E2 levels.

Results:

SP– efficiently enhanced HIV-1 R5 infection of CD4⁺ T cells, whereas SP+ enhancing activity was significantly reduced. RANTES (CCL5) concentrations were elevated in SP+ relative to SP–, whereas the concentrations of infectivity-enhancing peptides [semen-derived enhancer of viral infection (SEVI), SEM1, SEM2] were similar. CCR5 membrane expression levels were reduced on CD4⁺ T cells shortly postexposure to SP+ compared with SP– and correlated to R5-tropic HIV-1 infection levels, and CCR5 ligands’ concentrations in semen. SP+ and SP– displayed similar enhancing activity on PBMC infection by X4-tropic HIV-1. Addition/depletion of RANTES (regulated on activation, normal T-cell expressed and secreted) from SPs modulated their effect on PBMC infection by R5-tropic HIV-1.

Conclusion:

Semen from HIV-infected donors exhibits a significantly reduced enhancing potential on CD4⁺ T-cell infection by R5-tropic HIV-1 when compared with semen from uninfected donors. Our data indicate that elevated seminal concentrations of RANTES in HIV-infected men can influence the ability of semen to enhance infection.

Distinct cytokine/chemokine network in semen and blood characterize different stages of HIV infection

OBJECTIVE

The cytokine/chemokine network is used by the innate and adaptive immune system to orchestrate effective immune responses. Here, we describe the cross-sectional association between cytokine levels and stage of HIV infection to gain novel insights into HIV-1 immunopathogenesis and identify novel therapeutic targets.

DESIGN

Concentrations of 31 cytokine/chemokines were retrospectively measured in blood and seminal plasma collected from 252 individuals enrolled in four well characterized cohorts: HIV-uninfected, untreated HIV-infected in early phase of infection, untreated HIV-infected in late phase of infection, and HIV-infected on antiretroviral therapy with undetectable HIV RNA levels in blood (<50 copies/ml).

METHODS

Cytokine/chemokine levels were measured by multiplex-bead array. Comparisons between groups were performed by Mann-Whitney U-test and P values were adjusted for multiple comparisons using the Benjamini-Hochberg method.

RESULTS

Presence of HIV-infection skewed the cytokine/chemokine network towards a pro-inflammatory response in both blood and semen compared to HIV-uninfected controls. Such changes emerged within the first weeks of infection and were maintained thereafter: Among untreated HIV-infected individuals, none of the 31 measured cytokines were significantly different between early and later stages of infection. Suppression of plasma HIV RNA with ART did not result in normalization of the levels of pro-inflammatory cytokines in blood. In semen, several pro-inflammatory cytokines were even further upregulated in ART-treated compared with HIV-uninfected and HIV-untreated individuals.

CONCLUSION

A profound disruption in the cytokine/chemokine network is evident in blood and semen from the earliest stage of HIV infection shortly after the first detection of systemic viremia. These changes are maintained throughout the chronic phase of the infection and do not normalize despite ART and suppression of plasma HIV RNA.

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.

Differentiation-Coupled Induction of Human Cytomegalovirus Replication by Union of the Major Enhancer Retinoic Acid, Cyclic AMP, and NF-κB Response Elements

Triggers and regulatory pathways that effectively link human cytomegalovirus (HCMV) major immediate early (MIE) latent-lytic switch activation with progeny production are incompletely understood. In the quiescently infected human NTera2 cell model of primitive neural stem cells, we found that costimulation with vasoactive intestinal peptide (V) and phorbol ester (P) synergistically activated viral infection, but this effect waned over time. Coupling retinoic acid (R), an inducer of neuronal differentiation, to VP pulse stimulation attenuated the decline in viral activity and promoted the spread of the active infection through concentric layers of neighboring cells as cellular differentiation progressed. R stimulation alone was unable to activate the infection. The MIE enhancer cis-regulatory mechanisms responsible for this result were characterized by a strategy of combinatorial mutagenesis of five cis-acting element types (retinoic acid receptor binding elements [RARE], cyclic AMP [cAMP] response elements [CRE], NF-κB binding sites [kB], serum response element, and ETS/ELK-1 binding site) and multiple methods of assessment. We found that the CRE and kB combination sets the preinduction enhancer tone, is the major initiator and amplifier of RVP-induced MIE gene expression, and cooperates with RARE during cellular differentiation to enhance viral spread. In predifferentiated NTera2, we also found that the CRE-kB combination functions as initiator and amplifier of unstimulated HCMV MIE gene expression and cooperatively interacts with RARE to enhance viral spread. We conclude that RVP-stimulated signaling cascades and cellular differentiation operate through the enhancer CRE-kB-RARE core in strengthening induction of HCMV MIE gene expression in linkage with viral propagation.

IMPORTANCE

Cytomegalovirus-seropositive persons commonly lack detectable levels of cytomegalovirus replication, even when profoundly immunocompromised. In a human NTera2 cell model of primitive neural stem cells carrying resting cytomegalovirus genomes, we show that costimulation of protein kinase A and C-delta signaling cascades in conjunction with retinoic acid-induced neuronal differentiation brings about progeny virus propagation. Iterated DNA binding sites for retinoic acid receptor, CREB, and NF-κB family members in the cytomegalovirus major enhancer are at the crux in the pathway to HCMV activation. The stimulated CREB and NF-κB binding site combination vigorously initiates and amplifies the active cytomegalovirus infection and cooperates with activated retinoic acid receptor binding sites to further promote viral proliferation and spread between differentiated cells. These results support a paradigm in which a specific combination of stimuli coupled with cellular differentiation satisfies a core cis-activating code that unlocks enhancer silence to repower the cycle of cytomegalovirus propagation.

Blocking HIV-1 transmission in the female reproductive tract: from microbicide development to exploring local antiviral responses

The majority of new HIV-1 infections are transmitted sexually by penetrating the mucosal barrier to infect target cells. The development of microbicides to restrain heterosexual HIV-1 transmission in the past two decades has proven to be a challenging endeavor. Therefore, better understanding of the tissue environment in the female reproductive tract may assist in the development of the next generation of microbicides to prevent HIV-1 transmission. In this review, we highlight the important factors involved in the heterosexual transmission of HIV-1, provide an update on microbicides' clinical trials, and discuss how different delivery platforms and local immunity may empower the development of next generation of microbicide to block HIV-1 transmission in the female reproductive tract.

The Sordid Affair Between Human Herpesvirus and HIV

Both human immunodeficiency virus (HIV) and human herpesvirus (HHV) infections persist lifelong, and almost all individuals infected with HIV are also infected with ≥1 HHV. These coinfections are not independent processes or benign. In this review, we discuss how HHVs, and cytomegalovirus in particular, interact with concurrent HIV infection, and we describe the next steps necessary to understand and address these connections.

Critical Review: Immunomodulation by Seminal Factors and Implications for Male-to-Female HIV-1 Transmission

The role of semen in heterosexual transmission of the HIV-1 has been marginally viewed as an inert vehicle for the delivery of virus. However, studies from the field of reproductive biology have made it clear that seminal fluid is a complex and dynamic medium containing high concentrations of factors that play key roles in modulating the local immune response in the female reproductive tract during fertilization and embryogenesis. It is therefore strongly implied that the same seminal factors responsible for guiding the immune response in reproduction also play a role in male-to-female transmission of HIV-1. To begin to understand how these factors affect male-to-female HIV-1 transmission, multiple studies have comparatively profiled the contents of seminal fluid collected from uninfected and HIV-1-infected men. This review provides an overview of these studies, as well as a discussion of the potential impact of semen on HIV-1 transmission.

Genital Cytomegalovirus Replication Predicts Syphilis Acquisition among HIV-1 Infected Men Who Have Sex with Men

Objective

Sexually transmitted infections (STI) are common among HIV-infected men who have sex with men (MSM). While behavioral factors are important in STI acquisition, other biological factors such as immune modulation due to chronic viral infection may further predispose to STI acquisition.

Design

Post Hoc analysis including data collected over 12 months of follow-up from 131 HIV-infected MSM receiving antiretroviral therapy and screened for incident bacterial STI every 3 months.

Methods

Genital secretions collected at baseline were used to measure herpesvirus replication and inflammatory cytokines. Baseline predictors of STI were determined using survival analysis of time to incident STI.

Results

All participants were seropositive for cytomegalovirus (CMV), and 52% had detectable genital CMV at baseline. Thirty-five individuals acquired STI during follow-up, sometimes with multiple pathogen (17 syphilis, 21 gonorrhea, 14 chlamydia). Syphilis acquisition was associated with genital CMV replication at baseline (19.1% CMV-shedders versus 4.8% non-shedders, p=0.03) and younger age (p=0.02). Lower seminal MCP-1 was associated with higher seminal CMV levels and with syphilis acquisition (p<0.01). For syphilis acquisition, in multivariable Cox-Proportional Hazard model adjusted hazard rates were 3.56 (95%CI:1.00–12.73) for baseline CMV replication and 2.50 (0.92–6.77) for younger age.

Conclusions

This post hoc analysis suggest that CMV-associated decrease in seminal MCP-1 levels might predispose HIV-infected MSM to syphilis acquisition, but not other STI. Future studies should determine underlying mechanisms and if a causal association exists.

Seminal plasma HIV-1 RNA concentration is strongly associated with altered levels of seminal plasma interferon-γ, interleukin-17, and interleukin-5

Seminal plasma HIV-1 RNA level is an important determinant of the risk of HIV-1 sexual transmission. We investigated potential associations between seminal plasma cytokine levels and viral concentration in the seminal plasma of HIV-1-infected men. This was a prospective, observational study of paired blood and semen samples from 18 HIV-1 chronically infected men off antiretroviral therapy. HIV-1 RNA levels and cytokine levels in seminal plasma and blood plasma were measured and analyzed using simple linear regressions to screen for associations between cytokines and seminal plasma HIV-1 levels. Forward stepwise regression was performed to construct the final multivariate model. The median HIV-1 RNA concentrations were 4.42 log10 copies/ml (IQR 2.98, 4.70) and 2.96 log10 copies/ml (IQR 2, 4.18) in blood and seminal plasma, respectively. In stepwise multivariate linear regression analysis, blood HIV-1 RNA level (p<0.0001) was most strongly associated with seminal plasma HIV-1 RNA level. After controlling for blood HIV-1 RNA level, seminal plasma HIV-1 RNA level was positively associated with interferon (IFN)-γ (p=0.03) and interleukin (IL)-17 (p=0.03) and negatively associated with IL-5 (p=0.0007) in seminal plasma. In addition to blood HIV-1 RNA level, cytokine profiles in the male genital tract are associated with HIV-1 RNA levels in semen. The Th1 and Th17 cytokines IFN-γ and IL-17 are associated with increased seminal plasma HIV-1 RNA, while the Th2 cytokine IL-5 is associated with decreased seminal plasma HIV-1 RNA. These results support the importance of genital tract immunomodulation in HIV-1 transmission.

Innate and adaptive immune responses in male and female reproductive tracts in homeostasis and following HIV infection

The male and female reproductive tracts are complex microenvironments that have diverse functional demands. The immune system in the reproductive tract has the demanding task of providing a protective environment for a fetal allograft while simultaneously conferring protection against potential pathogens. As such, it has evolved a unique set of adaptations, primarily under the influence of sex hormones, which make it distinct from other mucosal sites. Here, we discuss the various components of the immune system that are present in both the male and female reproductive tracts, including innate soluble factors and cells and humoral and cell-mediated adaptive immunity under homeostatic conditions. We review the evidence showing unique phenotypic and functional characteristics of immune cells and responses in the male and female reproductive tracts that exhibit compartmentalization from systemic immunity and discuss how these features are influenced by sex hormones. We also examine the interactions among the reproductive tract, sex hormones and immune responses following HIV-1 infection. An improved understanding of the unique characteristics of the male and female reproductive tracts will provide insights into improving clinical treatments of the immunological causes of infertility and the design of prophylactic interventions for the prevention of sexually transmitted infections.

Role of semen in altering the balance between inflammation and tolerance in the female genital tract: does it contribute to HIV risk?

While the main reproduction aim of semen is the transport of spermatozoa to the female genital tract, seminal plasma is a complex fluid that also carries a broad array of immunologically active molecules. Seminal plasma has been shown to contain a diverse array of anti-inflammatory and pro-inflammatory soluble mediators that regulate immune responses within the female reproductive tract than can facilitate fertilization. Since the natural inflammatory response to semen deposition in the female genital tract may result in recruitment of activated HIV target cells into the female genital mucosa, we discuss the constituents of semen that may increase the risk for HIV infection in women.

HIV-1 vaginal transmission: cell-free or cell-associated virus?

The vast majority of new HIV infections in male-to-female transmission occurs through semen, where HIV-1 is present in two different forms: as free and as cell-associated virus. In the female lower genital tract, semen mixes with female genital secretions that contain various factors, some of which facilitate or inhibit HIV-1 transmission. Next, HIV-1 crosses the genital epithelia, reaches the regional lymph nodes, and disseminates through the female host. Cervico-vaginal mucosa contains multiple barriers, resulting in a low probability of vaginal transmission. However, in some cases, HIV-1 is able to break these barriers. Although the exact mechanisms of how these barriers function remain unclear, their levels of efficiency against cell-free and cell-associated HIV-1 are different, and both cell-free and cell-associated virions seem to use different strategies to overcome these barriers. Understanding the basic mechanisms of HIV-1 vaginal transmission is required for the development of new antiviral strategies to contain HIV-1 epidemics.