Discovery of 2,5-dimethoxy-substituted 5-bromopyridyl thiourea (PHI-236) as a potent broad-spectrum anti-human immunodeficiency virus microbicide

The increased risk of heterosexual transmission of human immunodeficiency virus-1 (HIV-1) has prompted the search for safe and effective female-controlled vaginal microbicides. Because endogenous reverse transcription is implicated in augmenting the sexual transmission of HIV-1, potential microbicides should have the inherent ability to optimally inhibit both wild-type and drug-resistant mutant strains of HIV-1. N-[2-(2,5-dimethoxyphenylethyl)]-N'-[2-(5-bromopyridyl)]-thiourea (PHI-236) is a rationally designed non-nucleoside inhibitor of HIV-1 reverse transcriptase (NNRTI) that was deduced from changes in binding pocket size, shape and residue character that result from clinically observed NNRTI resistance mutations. PHI-236 displayed high-binding affinity (Ludi K(i) = 0.07 microM) for HIV-1 RT and robust anti-HIV activity against the wild type (IC50 = <0.001 microM) as well as primary clinical isolates (IC50 = 0.009-0.04 microM) carrying multiple RT gene mutations associated with NRTI and NNRTI resistance. PHI-236 displayed high-selectivity index against human vaginal and cervical epithelial cells and did not affect human sperm functions. In the humanized severe combined immunodeficient mouse model for HIV/acquired immune deficiency syndrome (AIDS), pretreatment of HIV-1 (BaL)-infected human monocytes and semen with PHI-236 prevented the systemic infection via the vaginal route. PHI-236 has particular clinical utility as a non-spermicidal microbicide as well as a prophylactic antiviral agent to inactivate cell-free and cell-associated HIV-1 in semen before assisted reproductive technology procedures.

Detection of bovine herpesvirus-1 infection in breeding bull semen by virus isolation and polymerase chain reaction

Serum samples from 51 apparently healthy breeding bulls were screened for bovine herpesvirus-1 (BHV-1) antibodies using an avidin-biotin enzyme-linked immunosorbent assay, revealing a sero-positive prevalence rate of 45.09%. Semen samples were then collected from 12 of the sero-positive and 12 of the sero-negative bulls and tested for BHV-1 antigen using both a virus isolation assay and a polymerase chain reaction (PCR) assay; PCR was applied to detect BHV-1 deoxyribonucleic acid by using primers selected from the relatively conserved sequence of the gl glycoprotein gene to amplify a 468 base pair fragment. The PCR-amplified products were confirmed as BHV-1 by restriction enzyme, Dde 1, which produced fragments of predictable sizes, namely 340 and 128 base pairs. Positive virus isolation test results, confirmed by virus neutralisation, found BHV-1 antigen in the semen of five sero-positive and six sero-negative bulls. In comparison, positive PCR results found BHV-1 genome in the semen of six sero-positive and eight sero-negative bulls. From the 24 semen samples tested, 14 were shown to be positive by PCR and 11 by virus isolation. The sensitivity and specificity of virus isolation were 57.14% and 70% respectively, and were significantly lower than PCR. In the semen samples taken from sero-negative bulls, BHV-1 was detected more often by PCR methods than by virus-isolation, suggesting that PCR is a more sensitive method for BHV-1 screening in bulls.

HIV-specific CD8+ lymphocytes in semen are not associated with reduced HIV shedding

Sexual contact with HIV-infected semen is a major driving force behind the global HIV pandemic. Little is known regarding the immune correlates of virus shedding in this compartment, although HIV-1-specific CD8+ T cells are present in semen. We collected blood and semen from 27 chronically HIV-infected, therapy-naive men without common sexually transmitted infections or urethral inflammation and measured HIV-1 RNA viral load and cytokine/chemokine levels in both compartments. HIV-1 RNA levels were 10-fold higher in blood than semen, but discordantly high semen shedding was associated with higher semen levels of the proinflammatory cytokines IL-6, IL-8, IL-12, and IFN-gamma. Virus-specific CD8+ T cell epitopes were mapped in blood by IFN-gamma ELISPOT, using an overlapping HIV-1 clade B peptide matrix, and blood and semen CD8+ T cell responses were then assayed ex vivo using intracellular IFN-gamma staining. HIV-specific CD8+ responses were detected in 70% of semen samples, and their frequency was similar to or higher than blood. There was no correlation between the presence of virus-specific CD8+ T cells in semen and levels of HIV-1 RNA shedding. Among participants with detectable CD8+ IFN-gamma semen responses, their relative frequency was not associated with reduced HIV-1 RNA shedding, and their absolute number was correlated with higher levels of HIV-1 RNA semen shedding (r = 0.6; p = 0.03) and of several proinflammatory cytokines. Neither the presence nor the frequency of semen HIV-specific CD8+ T cell IFN-gamma responses in semen correlated with reduced levels of HIV RNA in semen.

Recovery of Swedish Equine arteritis viruses from semen by cell culture isolation and RNA transfection

Recovery of infectious Equine arteritis virus (EAV) from the semen of persistently infected Swedish stallions was attempted by classical cell culture isolation and by transfection of extracted total RNA. Whereas virus from semen samples stored for several months at -20 degrees C or from extended semen could only be recovered by transfection of extracted RNA, isolation in cell culture was achieved readily with fresh, unextended semen stored at -70 degrees C or directly used after sampling. In parallel, the viruses were examined in the variable region of the large glycoprotein GP5 by nested RT-PCR and direct nucleotide sequencing. The resulting sequences were placed into a large phylogenetic tree from this region, demonstrating that Swedish strains belonged to very diverse phylogenetic groups. This represents the first report of recovery of infectious EAV from archived semen samples by RNA transfection.

Disproportionately high semen shedding of HIV is associated with compartmentalized cytomegalovirus reactivation

Semen transmission of human immunodeficiency virus (HIV) drives the global pandemic. HIV loads are generally lower in semen than in blood, but semen loads may be disproportionately high in a subgroup of men. HIV loads in semen exceeded those in blood in 9 (35%) of 26 of antiretroviral therapy-naive men, and disproportionately high shedding was strongly associated with compartmentalized semen cytomegalovirus (CMV) reactivation (odds ratio [OR], 10.5; P<.01). Overall, 17 of 26 participants were shedding CMV in semen. Semen levels of HIV and CMV were closely correlated (r=0.5; P<.01), independently of blood HIV load and CD4(+) T cell count. Prevention of CMV reactivation warrants further study as a possible strategy to reduce semen shedding of HIV.

Hepatitis C virus in the semen of men coinfected with HIV-1: prevalence and origin

OBJECTIVE

To compare the prevalence of hepatitis C (HCV) RNA in semen from men infected with HCV and those coinfected with HIV-1/HCV and to study the origin of HCV shed in semen.

DESIGN

Two prospective studies (HC EP09 and BINECO) included 120 HCV-positive men, 82 coinfected with HIV-1; all had positive HCV RNA detection in blood.

METHODS

Paired blood and semen samples were collected for HCV RNA detection and quantification in seminal plasma and in blood serum; repeated semen samples were obtained for 45 men. HCV RNA was sought in spermatozoa and non-sperm cells. Phylogenetic analysis of the HVR-1 region of HCV compared the quasispecies in blood serum and seminal plasma of two men.

RESULTS

HCV RNA was more frequently found in the semen of men coinfected with HIV-1 (37.8%) than in those with only HCV infection (18.4%) (P = 0.033). HCV RNA detection in semen was intermittent and was positive in at least one semen sample of 42.8% of HIV-1/HCV-coinfected men who provided repeated samples. Men with HCV-positive semen had significantly higher HCV load in blood than men with HCV-negative semen (P = 0.038). Phylogenetic comparison of HCV quasispecies in blood and in semen showed no evidence of HCV replication in genital leukocytes; however, a phenetic structure was observed between compartments (P < 0.001).

CONCLUSIONS

HCV particles in semen originate from passive passage from blood, with preferential transfer of some variants. Nearly half of HIV-1/HCV-coinfected men may intermittently harbour HCV in their semen. Recommendations of protected sex for HIV-infected individuals should be reinforced.

[Sexual transmission of hepatitis C virus]

Hepatitis C virus (HCV) is usually transmitted parenterally, but sexual transmission is considered likely in the 20% of cases with no other risk factors. Retrospective cohort studies conducted among persons who have never injected drugs show that factors predictive of HCV seropositivity include the number of lifetime sexual partners, high-risk sexual practices, other sexually transmitted infections, and HIV seropositivity. Persons in long-term monogamous heterosexual relationships with a partner seropositive for HCV are at lower risk of HCV acquisition (0 to 0.6% peryear) than persons with multiple partners or those at risk for sexually transmitted diseases (0.4 to 1.8% per year). HCV RNA is detectable in genital fluids, but there is not yet any proof that the HCV RNA in genital secretions represents infectious virus. HCV can be transmitted by sexual intercourse but much less efficiently than other sexually transmitted viruses, such as HBV and HIV. Sexual transmission of HCV may be enhanced by other concomitant sexually transmitted infections with genital erosive lesions or via traumatic sexual intercourse with abrasion of the genital mucosa.

The use of endogenous and exogenous reference RNAs for qualitative and quantitative detection of PRRSV in porcine semen

Semen is known to be a route of porcine reproductive and respiratory syndrome virus (PRRSV) transmission. A method was developed for qualitative and quantitative detection of the seminal cell-associated PRRSV RNA in relation to endogenous and exogenous reference RNAs. As endogenous control for one-step real-time reverse transcription (RT)-PCR UBE2D2 mRNA was selected. Particularly for the analysis of persistent infections associated with low copy numbers of PRRSV RNA, UBE2D2 mRNA is an ideal control due to its low expression in seminal cells and its detection in all samples analysed (n = 36). However, the amount of UBE2D2 mRNA in porcine semen varied (up to 106-fold), thus its use is limited to qualitative detection of PRRSV RNA. For quantitation, a synthetic, non-metazoan RNA was added to the RNA isolation reaction at an exact copy number. The photosynthesis gene ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit (rbcL) from Arabidopsis thaliana was used as an exogenous spike. Unexpectedly, PRRSV RNA was detected in a herd of specific pathogen-free (SPF) boars which were tested ELISA-negative for anti-PRRSV antibodies. Therefore, RT-PCR for seminal cell-associated PRRSV is a powerful tool for managing the SPF status during quarantine programs and for routine outbreak investigations.

Isolation of human immunodeficiency virus type 1 from semen and vaginal fluids

Semen and vaginal fluids transmit HIV infection. The virus is present as cell-free particles and as infected cells. Isolation of infectious virus from both genital tract fluids poses unique problems. Vaginal fluids are heavily contaminated with normal bacterial flora, and seminal plasma is cytotoxic to peripheral blood mononuclear cells. Adaptations of routine laboratory procedures have been developed to largely overcome these problems, allowing the culture and characterization of genital-tract HIV.

Quantitation of HIV-1 viral RNA in blood plasma and genital secretions

Quantitation of HIV RNA in blood is commonly used to monitor progression of the disease and to assess the effect of antiretroviral therapy in individuals. Although not approved in the US for diagnosis of HIV infection, the finding of a positive HIV RNA with a negative HIV enzyme immunoassay and Western blot (or evolving Western blot) is an indication of primary HIV infection and should be followed up closely. Large clinical trials and cohort studies have demonstrated the importance of HIV RNA as an indicator of drug efficacy and as a factor in HIV transmission. Sexual intercourse is the most common method of transmission of HIV-1. Several studies have demonstrated that blood plasma viral load is significantly correlated with the risk of sexual HIV transmission. Additional investigations have found a significant correlation between the viral load in blood plasma and in the genital tract. This chapter describes methods of collection, processing, and testing in blood, plasma, and male and female genital secretions for quantifying HIV RNA.

Pathophysiology of HIV-1 in semen: current evidence for compartmentalisation and penetration by antiretroviral drugs

Sexual transmission of HIV-1 is dependent on the semen viral load. Seminal viral load may fluctuate and is increased by several HIV-1 related factors and prevailing conditions within the male genital tract. The precise reservoirs of virus production within the male genital tract, whether cell-associated of cell-free, are undefined. The ability of antiretroviral drugs to penetrate the male genital tract and reach therapeutic concentrations is correlated with the degree of viral suppression and therefore relative infectivity. The basic physicochemical properties of the drugs themselves do not predict penetration of semen and other factors, such as active drug transport, may be involved. Measurement of seminal viral load and antiretroviral drug concentration are affected by the physiology of semen and non-standardised methodology (type of test used, specimen collection methods, data presentation issues, and pharmacokinetic assumptions) between studies.

Rapid quantification of semen hepatitis B virus DNA by real-time polymerase chain reaction

AIM: To examine the sensitivity and accuracy of real-time polymerase chain reaction (PCR) for the quantification of hepatitis B virus (HBV) DNA in semen.

METHODS: Hepatitis B viral DNA was isolated from HBV carriers’ semen and sera using phenol extraction method and QIAamp DNA blood mini kit (Qiagen, Germany). HBV DNA was detected by conventional PCR and quantified by TaqMan technology-based real-time PCR (quantitative polymerase chain reaction (qPCR)). The detection threshold was 200 copies of HBV DNA for conventional PCR and 10 copies of HBV DNA for real time PCR per reaction.

RESULTS: Both methods of phenol extraction and QIAamp DNA blood mini kit were suitable for isolating HBV DNA from semen. The value of the detection thresholds was 500 copies of HBV DNA per mL in the semen. The viral loads were 7.5 × 10⁷ and 1.67 × 10⁷ copies of HBV DNA per mL in two HBV infected patients’ sera, while 2.14 × 10⁵ and 3.02 × 10⁵ copies of HBV DNA per mL in the semen.

CONCLUSION: Real-time PCR is a more sensitive and accurate method to detect and quantify HBV DNA in the semen.

Seminal reservoirs during an HIV type 1 eradication trial

Despite dramatic reduction of the levels of human immunodeficiency virus type I (HIV-1) virions in blood and seminal plasma of infected patients, highly active antiretroviral therapy (HAART) does not eradicate HIV-1. Three patients, with less than 50 copies/ml of plasma viral RNA, were enrolled in this eradication protocol. Didanosine (DDI) and hydroxyurea (HU) were added to their baseline HAART and after a month of therapy, low dose OKT3, followed by a 2-week course of interleukin 2 (IL-2), was administrated. All antiretroviral therapy was then interrupted and the three patients developed viral rebound in the peripheral blood. The V3 loop region of the HIV-1 gp120 from cell-free viral RNA and proviral DNA in blood and seminal compartments was sequenced in one patient. The two major viral isolates in semen cells were macrophage- tropic (R5) and dual-tropic (R5X4), and these isolates were also present in the PBMCs. Six months after the viral rebound, we demonstrated a shift toward dual tropism in semen cell-associated HIV-1 proviral DNA, with the first appearance of a T-lymphotropic (X4) provirus solely in this compartment. The virus responsible for the blood plasma viral rebound was never found in the semen microenvironment. This study suggests viral compartmentalization of the semen microenvironment after an intensification and stimulatory HIV-1 eradication protocol, with evidence of viral evolution.

Non-transmission of bacterial and viral microbes to embryos and semen stored in the vapour phase of liquid nitrogen in dry shippers

Cryopreservation and storage of germplasm is an important factor in the prevention of disease transmission by embryo transfer and artificial insemination. Here we report the results of an investigation on transmission of selected bacterial and viral pathogens by the vapour phase of liquid nitrogen (VPLN) to embryos and semen in dewars designed for short-term storage and transportation of biological specimens. In this study transmission of Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, BVDV, and BHV-1 was examined from: (1) contaminated dry shippers to germplasm; (2) between contaminated and non-contaminated cryopreserved germplasm; and (3) between stock culture of pathogenic agents and germplasm. Contaminated and non-contaminated samples of embryos and semen were stored in proximity in the vapour phase LN in open containers for 7 days prior to testing for the presence of microbes. The results showed that there was no cross-contamination from either the contaminated dewars to germplasm or between contaminated and non-contaminated samples of embryos and semen during 7 days storage under LN vapours. The outcome of our investigation indicates that VPLN is a safe means for short-term storage of embryos and semen in dry shipper dewars commonly used for transportation of bovine germplasm.

Ex vivo modeling of oral HIV transmission in human palatine tonsil

The majority of newly acquired HIV infections are believed to occur following transmission of virus infectivity across mucosal surfaces, although many mechanistic details still remain unresolved. We have used human ex vivo organ cultures and primary cell populations to analyze the cellular and molecular basis for mucosal HIV transmission. By using human palatine tonsil from routine tonsillectomies and semen from HIV-positive donors, we have created an experimental equivalent to oral HIV transmission. HIV infection was readily transferred into tonsillar lymphocytes, but this transmission into lymphocytes was dramatically reduced when the exposed lymphocyte populations were protected by intact mucosal surfaces. In this study, we consider the impact that leukocyte activation and morphological aberrations in surface structure may have on susceptibility to primary HIV infection and introduce novel time-lapse confocal microscopy procedures that begin to reveal the dynamic complexity associated with cell-mediated HIV transmission.

The effects of urethritis on seminal plasma HIV-1 RNA loads in homosexual men not receiving antiretroviral therapy

OBJECTIVES

To examine the effects of urethritis and its treatment on semen plasma HIV-1 RNA load in HIV-1 infected men not receiving antiretroviral therapy (ART), in a developed world setting.

METHODS

Prospective case-control study. HIV-1 infected homosexual men, not receiving ART for at least 3 months, with (cases) and without (controls) symptomatic urethritis, were recruited. Blood and semen were collected for HIV-1 RNA quantification at presentation, before antibiotic therapy, and at 1 and 2 weeks.

RESULTS

20 cases (13 gonococcal urethritis and/or chlamydial urethritis (GU/CU) and seven non-specific urethritis (NSU)) and 35 controls were recruited. Baseline characteristics and blood plasma viral load were similar in cases and controls. Mean log semen plasma viral loads were higher among those with GU/CU compared with controls (4.27 log versus 3.55 log respectively; p = 0.01) but not in those with NSU (3.48 log; p = 0.82). Following antibiotics, semen plasma viral loads fell by a mean of 0.25 log (95% CI: 0.03 to 0.47) in those with GU/CU. Semen plasma viral loads did not fall in those with NSU.

CONCLUSIONS

In this study of 55 homosexual men not on ART, semen plasma viral loads were approximately fivefold higher in those with GU/CU, but not NSU, compared with controls. Treatment of GU/CU resulted in reduction in semen plasma viral loads. Although absolute effects were considerably lower when compared to patients from a similar study from sub-Saharan Africa, our data demonstrate the potential for sexually transmitted infections to enhance HIV infectivity of men not receiving ART in the developed world.

[Insemination from HIV-positive males]

INTRODUCTION

Discordant couples, in which the man is HIV positive and the woman is HIV negative, face limited options when they wish to produce healthy children whilst practicing safe sex. In order to conceive they must abandon unprotected sex, which carries high risk of HIV infection to the woman.

OBJECTIVE

To develop a method for removing the HIV from semen and then perform intra uterine insemination, following verification of the HIV-negative spermatozoa fraction by PCR.

METHODS

Motile spermatozoa were isolated from semen samples by the gradient and "swim-up" techniques. HIV-RNA was tested before and after the procedure in both the semen and the purified spermatozoa fraction. Insemination was performed on ovulation day only when the absence of any viral particles was verified by PCR.

RESULTS

Four couples underwent a total of 8 cycles of intra uterine insemination (IUI). Presently, two healthy babies were born. The two mothers and newborn were found to be HIV negative following the delivery.

CONCLUSION

We report a safe procedure which enables biological parenthood for HIV-1 discordant couples without the risk of infecting the female partner. Our clinical data corroborate with the collaborative European data on this subject.

The risks posed by the importation of animals vaccinated against foot and mouth disease and products derived from vaccinated animals: a review

The Terrestrial Animal Health Code of the OIE (World organisation for animal health) (the Terrestrial Code) makes recommendations for international movements of live animals and animal products because of a possible generic risk of foot and mouth disease (FMD) for these different commodities. For instance, international movement of vaccinated live animals or products of such animals is restricted due to the possible masking of clinical disease as a result of vaccination and to the perceived risk of persistently infected animals among vaccinated livestock. In addition, bilateral agreements between exporting and importing countries on the importation of animal products can be based on the 'equivalence' of the animal health conditions in both countries, or on formal or informal risk assessments in accordance with the norms and recommendations of the Terrestrial Code. In this regard, an exporting country may be required to prepare a complete and transparent document describing the animal health situation, including the factors required to assess the risk involved. Furthermore, expert committees of importing countries regularly evaluate and verify these conditions in exporting countries. The level of confidence in the information obtained by the expert committee can then be entered into the risk analysis equation. An important FMD risk reduction factor for the importation of animals and animal products is early recognition of the disease at the source of the commodity by alert stakeholders, such as official and private veterinarians and the chain of the livestock industry. This is true for all countries irrespective of their vaccination status. The risk posed by the importation of vaccinated animals becomes negligible when an adequate protocol--in compliance with the norms and recommendations of the Terrestrial Code--is applied. However, recently, export of live animals from countries that do not practise vaccination has also proven to pose a significant risk and the rules governing such transport may have to be reviewed. Disease surveillance, biosecurity at the farm level, traceability and control of the source cattle and slaughterhouse inspections are the main risk reduction measures for meat and meat products from vaccinated cattle. If these animals are slaughtered and processed under good management practice--in accordance with the norms and recommendations of the Terrestrial Code--these products present a negligible risk for the introduction of FMD. Risk reduction by maturation and deboning is an important procedure, but is probably overemphasised. Mechanical contamination of cattle carcasses with 'carrier virus' from the pharyngeal area during slaughter and processing is very unlikely. Risk assessments showed that the importation of milk products from countries or zones that practise vaccination of dairy herds poses a negligible risk. Risk assessments also demonstrated that the importation of bovine embryos from vaccinated cows--in accordance with the norms and recommendations of the Terrestrial Code--poses a negligible risk. Likewise, the risk from the importation of semen from vaccinated bulls is also negligible when an adequate test protocol is applied in accordance with the Terrestrial Code.

Semen characteristics in human immunodeficiency virus (HIV)- and hepatitis C (HCV)-seropositive males: predictors of the success of viral removal after sperm washing

BACKGROUND

Human immunodeficiency virus (HIV)/hepatitis C virus (HCV)-seropositive males can now father children safely, avoiding transmission risks to the mother and the children using sperm washing and nested PCR (nPCR) techniques. Nevertheless, we still lack enough data to determine the reasons why approximately 10% of the performed sperm washes remain positive, thus forcing the repetition of the treatment. Semen quality in infected males is also essential to these procedures. We aimed to determine the predictive value of the semen parameters, sperm washing procedure and the infection status for the post-wash viral positivity, as well as the correlation between the semen and the disease features.

METHODS

Semen characteristics were evaluated in 136 samples provided from 125 males. We also included a control group of 125 males matched by age and length of sexual abstinence. At the time of semen retrieval, 70 of them were infected with HIV (45 also with HCV, 64.3%), and 55 of them with HCV alone. nPCR for viral detection was performed in each sample.

RESULTS

Thirteen out of 136 (9.5%) of the samples were positive for one or more viral detections (HIV RNA, HIV DNA and HCV RNA, when needed). From a total of 240 nPCR viral analyses, 16 were positive (6.6%). None of the seminal parameters were adequate to predict post-wash results, nor was a positive result dependent on the volumes used in the semen wash. A positive correlation was found between post-wash progressive motility and CD4 blood levels, as well as a negative correlation between progressive motility and time of evolution of the disease in HIV-infected males.

CONCLUSIONS

Semen analysis, according to the World Health Organization criteria, of HIV- and HCV-affected patients showed no differences from that of non-infected males. Moreover, low CD4 blood levels, and a long evolution of the disease do not negatively affect sperm motility.

[Impact of reverse transcriptase inhibitors on sperm mitochondrial and genomic DNA in assisted reproduction techniques]

For the last ten years, antiretroviral therapy (ARV) has improved the prognosis in HIV-1 infection and showed a better control of the viral excretion by reducing viral shedding in semen. However, nucleoside analogues reverse transcriptase inhibitors (NRTI) therapy reported important adverse effects. Most of these side effects observed seem to be linked with a common mechanism: mitochondrial activity alteration. Since the introduction of protocols for HIV-1 serodiscordant couples, with male infected partners under NRTI therapy, many results in the literature such as: semen characteristics and pregnancies, drew the attention of research teams. Many studies have suggested that NRTI has an affect on semen parameters, but proposed mechanisms of these effects have rarely been discussed. NRTI have a great affinity for the reverse transcriptase of HIV-1. Because many NRTI are not only inhibitors of reverse transcriptase but also inhibitors of the DNA polymerase beta and gamma, several toxic effects can be considered. Nevertheless, this specificity is not absolute and "accidental" incorporations of NRTI can occur on genomic sperm DNA. Only one study on genomic sperm DNA with patients under NRTI therapy was published without concluding results. Recently, studies have suggested that NRTI exposure could induce an alteration on mitochondrial energy-generating ability of spermatozoa. NRTI are known to induce an increase in the generation of reactive oxygen species, which results in the degradation of mitochondrial transmembrane potential (Deltapsim). This loss of Deltapsim can tend to release some specific apoptosis factors, such as cytochrome c, that initiates programmed cell death. Sperm DNA fragmentation, associated to apoptosis, was reported as a possible cause of recurrent pregnancy loss. If the incorporation of NRTI was reported in genomic DNA of somatic cells, the absence of data on the genomic sperm DNA justifies further studies concerning the effects of paternal exposure to NRTI on the genomic material of the male gamete, in particular because of its implication in the zygote development after fertilization.

Sperm washing, use of HAART and role of elective Caesarean section

PURPOSE OF REVIEW

Today, 50% of people living with HIV are women and most have been sexually infected. Highly active antiretroviral therapy (HAART) reduces the rates of both sexual and vertical infection, but maximum protection is achieved with sperm washing and elective Caesarean section.

RECENT FINDINGS

Men taking HAART have lower seminal concentration of HIV, and sexual transmission may be reduced. However, a certain percentage of aviraemic men retain viral presence in semen, and unprotected intercourse to achieve fertilization must be discouraged as it carries the risk of sexual transmission of the virus. HIV-discordant couples should be informed that sperm washing can remove HIV from semen, allowing conception without the risk of infection for the seronegative female and eventually the child. In HIV-positive women, perinatal transmission of HIV can be curtailed to less than 2% by using HAART to decrease maternal viral load and offering prenatal preexposure prophylaxis of the fetus, and elective Caesarean section. Each intervention carries specific risks and benefits. The contribution of each preventive arm in achieving fetal protection can only be crudely measured and optimal obstetric management must involve discussion with the pregnant woman of the pros and cons of each strategy.

SUMMARY

In HIV-positive men taking HAART, seminal viral load is decreased but not eliminated and fertilization should be achieved through sperm washing to offer maximum protection for the uninfected female. Pregnant HIV-positive women on antiretroviral medication have a reduced risk of transmitting the virus, but should still be counselled about the possibility to further limit the chances of infecting their infant through elective Caesarean section.

Viruses in boar semen: detection and clinical as well as epidemiological consequences regarding disease transmission by artificial insemination

Many viruses have been reported to be present in boar semen, particularly during the viremic phase of the diseases. Some of them, such foot-and-mouth disease virus, porcine reproductive and respiratory syndrome virus, swine vesicular disease virus, porcine parvovirus, picornaviruses, adenoviruses, enteroviruses, Japanese encephalitis virus, pseudorabies virus, African swine fever virus and reoviruses are of particular importance and accurate monitoring prior to and during the presence of boars in AI stations is essential. Various methods may be used to detect these viruses in the animals, or even directly in batches of semen. Cell culture, ELISA and PCR are the most accurate and widely used. Because of the high risk of dissemination of disease via AI, the absolute goal is to provide pathogen-free semen and this is feasible with the adequate measures that are discussed briefly in this paper.

HIV epidemics driven by late disease stage transmission

How infectious a person is when infected with HIV depends on what stage of the disease the person is in. We use 3 stages, which we call primary, asymptomatic, and symptomatic. It is important to have a systematic method for computing all 3 infectivities so that the measurements are comparable. Using robust modeling, we provide high-resolution estimates of semen infectivity by HIV disease stage. We find that the infectivity of the symptomatic stage is far higher, hence more potent, than the values that prior studies have used when modeling HIV transmission dynamics. The stage infectivity rates for semen are 0.024, 0.002, and 0.299 for the primary, asymptomatic, and symptomatic stages, respectively. Implications of our infectivity estimates and modeling for understanding heterosexual epidemics such as that in sub-Saharan African are explored.

Transmission of high-risk human papillomavirus (HPV) between parents and infant: a prospective study of HPV in families in Finland

The Finnish HPV Family Study is a prospective cohort study assessing the dynamics of human papillomavirus (HPV) transmission between parents and infant. Serial genital and oral scrapings from 76 families, including mother, father, and infant, and semen samples were collected over 2 years of follow-up, analyzed by nested PCR, and confirmed by hybridization with 12 high-risk (HR) HPV types. The most common HPV profile was HR HPV in all family members (29%), followed by HPV-positive mother-infant pairs (26%). HPV-positive father-infant pairs were less frequent (11%), and in six (8%) families, only the infant was HR HPV positive. The prevalence of genital HR HPV in the parents ranged from 13 to 25%, and that of oral HPV ranged from 8 to 34%. In the infants, HPV DNA was detected in 15% of the genital and 10% of the oral samples at birth, reaching peaks of 18 and 21%, respectively, at 6 months, and declining to 10% at 24 months. Persistent HPV in the mother was a risk factor for oral HPV in the infant (odds ratio [OR], 5.69; 95% confidence interval [95% CI], 1.5 to 21.3), while oral HPV in the mother at 6 months was a risk factor for genital HR HPV (OR, 6.38; 95% CI, 1.15 to 35.32). No such independent risk could be attributed to subclinical HPV in the father. Persistent maternal cervical HPV and subclinical oral HPV affect the risk of infant HPV. The age of 6 months is a critical point for the infant to acquire or be free of HR HPV DNA.