Influence of inguinal hernia repair on sperm autoimmunity: The largest single center experience.

BACKGROUND: Studies on immunological infertility after inguinal hernia correction are few and not very representative. Anti-sperm antibodies have been shown to reduce male fertility. Although the extent of infertility due to anti-sperm antibodies alone is not very clear, data indicates that about 8%-10% of infertile patients have immunological infertility DESIGN: This retrospective study includes all infertile male patients (n = 2258) who underwent mixed antiglobulin reaction tests and urologic examination from 2000 to 2020. Sperm quality (assessed by the number of spermatozoa, their motility, vitality, and normal form) was also evaluated. Among these patients, 191 had previously undergone unilateral or bilateral inguinal hernia surgery repair. The aim of the study is to evaluate if there is a higher incidence of positive mixed antiglobulin reaction test among patients undergoing inguinal hernioplasty compared to the unselected infertile population. RESULTS: Anti-sperm antibodies would seem to increase in both patients who performed general andrological surgery and groin hernia correction, respectively 3.48 (95% Confidence Interval: 1.70-7.10; p < 0.001) and 2.45 (95% Confidence Interval: 1.01-5.99; p < 0.05) times more than the unselected infertile population. CONCLUSIONS: Mixed antiglobulin reaction test could be useful in patients undergone previous scrotal surgery or hernia correction men, to avoid false unexplained infertility diagnoses and to direct the couple to assisted reproductive technology procedures. Basal evaluation of spermatozoa does not actually consider andrological surgery as an indication to autoimmunity investigation.

Hexavalent sperm-binding IgG antibody released from vaginal film for development of potent on-demand nonhormonal female contraception.

Nonhormonal products for on-demand contraception are a global health technology gap; this unmet need motivated us to pursue the use of sperm-binding monoclonal antibodies to enable effective on-demand contraception. Here, using the cGMP-compliant Nicotiana-expression system, we produced an ultrapotent sperm-binding IgG antibody possessing 6 Fab arms per molecule that bind a well-established contraceptive antigen target, CD52g. We term this hexavalent antibody "Fab-IgG-Fab" (FIF). The Nicotiana-produced FIF had at least 10-fold greater sperm-agglutination potency and kinetics than the parent IgG, while preserving Fc-mediated trapping of individual spermatozoa in mucus. We formulated the Nicotiana-produced FIF into a polyvinyl alcohol-based water-soluble contraceptive film and evaluated its potency in reducing progressively motile sperm in the sheep vagina. Two minutes after vaginal instillation of human semen, no progressively motile sperm were recovered from the vaginas of sheep receiving FIF Film. Our work supports the potential of multivalent contraceptive antibodies to provide safe, effective, on-demand nonhormonal contraception.

Identification of Arvicola terrestris scherman Sperm Antigens for Immune Contraceptive Purposes.

The cyclical proliferation of the wild fossorial rodent Arvicola terrestris scherman (ATS) is critical in mid-mountain ecosystems of several European countries. Our goal is to develop an immunocontraceptive vaccine to control their fertility, as a sustainable alternative to chemical poisons currently used. Indeed, these chemicals cause the death of ATS predators and animals sharing their ecosystem, and current laws progressively limit their use, making the development of a targeted vaccination strategy an interesting and efficient alternative. In order to identify species-specific sperm antigens, male and female ATS received subcutaneous injections of whole ATS spermatozoa to elicit an immune response. The analysis of the immune sera led to the identification of 120 immunogenic proteins of sperm cells. Of these, 15 were strictly sperm-specific and located in different regions of the male gamete. Some of these antigens are proteins involved in molecular events essential to the reproductive process, such as sperm-egg interaction, acrosomal reaction, or sperm motility. This approach not only identified a panel of immunogenic proteins from ATS sperm cells, but also demonstrated that some of these proteins trigger an immune response in both male and female ATS. These spermatic antigens are good candidates for the development of a contraceptive vaccine.

Production and characterization of a human antisperm monoclonal antibody against CD52g for topical contraception in women.

BACKGROUND: Approximately 40% of human pregnancies are unintended, indicating a need for more acceptable effective contraception methods. New antibody production systems make it possible to manufacture reagent-grade human monoclonal antibodies (mAbs) for clinical use. We used the Nicotiana platform to produce a human antisperm mAb and tested its efficacy for on-demand topical contraception. METHODS: Heavy and light chain variable region DNA sequences of a human IgM antisperm antibody derived from an infertile woman were inserted with human IgG1 constant region sequences into an agrobacterium and transfected into Nicotiana benthamiana. The product, an IgG1 mAb ["Human Contraception Antibody" (HCA)], was purified on Protein A columns, and QC was performed using the LabChip GXII Touch protein characterization system and SEC-HPLC. HCA was tested for antigen specificity by immunofluorescence and western blot assays, antisperm activity by sperm agglutination and complement dependent sperm immobilization assays, and safety in a human vaginal tissue (EpiVaginal™) model. FINDINGS: HCA was obtained at concentrations ranging from 0.4 to 4 mg/ml and consisted of > 90% IgG monomers. The mAb specifically reacted with a glycan epitope on CD52g, a glycoprotein produced in the male reproductive tract and found in abundance on sperm. HCA potently agglutinated sperm under a variety of relevant physiological conditions at concentrations ≥ 6.25 µg/ml, and mediated complement-dependent sperm immobilization at concentrations ≥ 1 µg/ml. HCA and its immune complexes did not induce inflammation in EpiVaginal™ tissue. INTERPRETATION: HCA, an IgG1 mAb with potent sperm agglutination and immobilization activity and a good safety profile, is a promising candidate for female contraception. FUNDING: This research was supported by grants R01 HD095630 and P50HD096957 from the National Institutes of Health.

Xiaokang Liuwei Dihuang decoction ameliorates the immune infertility of male rats induced by lipopolysaccharide through regulating the levels of sex hormones, reactive oxygen species, pro-apoptotic and immune factors.

Male immune infertility is a kind of disease that damages family life and happiness. The development of novel methods treating male immune infertility is of great significance. This study aimed to investigate the therapeutic effects of Chinese medicine Xiaokang Liuwei Dihuang decoction on immune infertility of male rats and explored the involved mechanisms. Model rats were established by lipopolysaccharide (LPS) injection. Anti-sperm antibody (AsAb) was detected by ELISA assay and testicular cell apoptosis was evaluated by TUNEL staining to verify the successful model establishment and screen suitable doses of Xiaokang Liuwei Dihuang decoction. Thirty rats were then divided into five groups (n = 6 per group): Control, LPS, Xiaokang Liuwei Dihuang decoction (15.12 g/kg, 30.24 g/kg and 45.36 g/kg). Results of HE staining showed that compared with LPS group, Xiaokang Liuwei Dihuang decoction treatments gradually improved the morphology of seminiferous tubules and elevated the number of spermatogenic cells as the doses increased. The sperm number and the levels of testosterone, luteinizing hormone (LH) and follicle stimulating hormone (FSH) in the serum of 15.12 g/kg, 30.24 g/kg and 45.36 g/kg Xiaokang Liuwei Dihuang decoction groups were much higher than those in LPS group. Results of TUNEL staining, ELISA assay and western blot showed that compared with LPS group, the testicular cell apoptosis and the levels of interleukin 1ß (IL-1ß), tumor necrosis factor α (TNF-α), AsAb, malondialdehyde (MDA) and toll-like receptor 2 (TLR2) in the testicular tissue significantly decreased in three Xiaokang Liuwei Dihuang decoction groups. Compared with LPS group, Bax expression in the 30.24 g/kg and 45.36 g/kg Xiaokang Liuwei Dihuang decoction groups was significantly down-regulated as well. In conclusion, Xiaokang Liuwei Dihuang decoction might ameliorate the immune infertility of male rats induced by LPS through regulating the levels of sex hormones, reactive oxygen species, pro-apoptotic and immune factors.

Immunological response of fallopian tube epithelial cells to spermatozoa through modulating cytokines and chemokines.

BACKGROUND: Spermatozoa interactions with fallopian tubes may influence fertilization. The purpose was to investigate cytokines, chemokines and growth factors expression from human fallopian tube epithelial cells (OE-E6/E7) exposed to spermatozoa. METHODS: Fresh semen samples were obtained from 10 healthy normozoospermic men. Sperms were prepared and co-cultured with OE-E6/E7. The cell line without spermatozoa was considered as the control group. Afterwards, Expression of 84 cytokines from OE-E6/E7 cell line in the presence and absence of spermatozoa were measured using PCR-array. Quantitative PCR was performed on seven genes to confirm the results of PCR-array analysis. Differentially expressed genes were subjected to www.geneontology.org and www.pantherdb.org to perform GO enrichment and panther pathway analysis. The concentration of IL-8, IL-10, IL-1B and BMP-4 in culture medium were analyzed by ELISA. RESULTS: Sperm interaction with the epithelial cells resulted in a significant increase in expression of TGF-ß2, BMP-4, IL-10, IL-9, and CD40LG markers. Moreover, expression of IL-16, IL-17F, SPP-1, CXCL-13, MSTN, IL-1A, IL-1B, IL-8, BMP-7, CSF-2, CSF-3, VEGF-A, OSM, LTA, TNF, TNFRSF11B, TNFSF11, CCL-11, CCL-20, CCL-24, CCL-3, CCL-8, CX3CL1 and CXCL-9 were considerably reduced in presence of spermatozoa. Panther pathway analysis discovered 3 pathways for upregulated genes including gonadotropin-releasing hormone receptor, TGF-beta and interleukin signaling pathways. Furthermore, 9 pathways were detected for down-regulated genes. Inflammation signaling pathway which is mediated by chemokine and cytokine contains the most number of genes. CONCLUSION: This study indicates that sperm modifies expression of cytokines, chemokines and growth factors from OE-E6/E7. Moreover, altered genes expression are toward higher survival chance of the spermatozoa.

The Male Is Significantly Implicated as the Cause of Unexplained Infertility.

Male infertility is recognized as a relatively common, complex condition, generated by a broad array of environmental and genetic factors. Historical reliance on the conventional semen profile has tended to underestimate the true contribution of "the male factor" to human infertility. This review highlights the importance of genetic and epigenetic factors in the etiology of male infertility, identifying a range of mutations responsible for primary testicular failure and impaired fertilizing potential. More than three quarters of all de novo mutations arise in the male germline via mechanisms that involve the inefficient or defective repair of DNA damage. Understanding the range of factors capable of creating genetic turmoil in the paternal germline is essential, if we are to gain a deep understanding of the causes of male infertility, rather than just the symptoms that characterize its presence. High levels of DNA fragmentation induced by oxidative stress are part of this equation. Oxidative stress is, in turn, driven by biological (age, ejaculation frequency, varicocele, infection), lifestyle (smoking, obesity), and environmental factors (heat, other forms of electromagnetic radiation, and toxins) that can impair the fertilizing potential of the spermatozoa and influence the incidence of spontaneous mutations that may cause infertility in the offspring.

Successful activation of rat T lymphocytes by sperm specific antigens in vitro.

Autoimmune orchitis is a condition related to cellular immunity. A disease model involving transfer of T lymphocytes activated by known antigens would be useful for defining pathogenical molecules. Since no method for activating rat T cells using specific antigens is available, we started the study to develop the method. T cells were collected from draining lymph nodes of immunized rats, then co-cultured with syngeneic splenocytes as antigen-presenting cells (APC) in antigen-supplemented medium (= stimulation). The cells were then incubated in medium without antigens and APC (= resting). Repetitive stimulation and resting increased the number of the T cells more than 100-fold. The antigen-specific activation was demonstrated by cell proliferation assay and ELISA assay for interferon gamma. Flow cytometry revealed that > 95% of the cells expressed tumor necrosis factor alpha, a cytokine responsible for autoimmune orchitis. The present method will provide a new procedure to evaluate antigenicity of sperm molecules.

Toll-like receptor 2 mediates the immune response of the bovine oviductal ampulla to sperm binding.

We previously reported that sperm binding to cultured bovine oviduct epithelial cells induces an anti-inflammatory immune response. Now we have developed a differentiated explant model to focus on the oviductal ampulla, where fertilization occurs, and to study the effect of sperm capacitation on the immune response. We used heparin to stimulate bovine sperm capacitation. Fluorescence imaging showed that 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolyl-carbocyanine iodide-labeled sperm pretreated with (Hep(+) ) or without (Hep(-) ) heparin rapidly attached to the explant ciliated epithelium in similar numbers. However, only Hep(+) sperm upregulated explant messenger RNA (mRNA) transcription of TLR2, IL8, TGFB1, and PGES, without changes in TNFA and IL-10 expression, while Hep(-) sperm only upregulated PGES. The responses were primarily anti-inflammatory, with a greater response produced by Hep(+) sperm, which also produced a substantial increase in TLR2 protein expression in the epithelium. The addition of TLR1/2 (toll-like receptor 1/2) antagonist to the Hep(+) and (Hep(-) ) sperm-explant coincubations reduced sperm attachment to the epithelium and inhibited TLR2 protein expression and some of the Hep(+) sperm-induced mRNA transcription. Our observations suggest that the ampullar epithelium immunologically reacts more strongly to sperm that have undergone heparin stimulation of capacitation. This anti-inflammatory response could serve to protect capacitated sperm as they approach the oocyte in the ampulla.

Natural killer and NKT cells in the male reproductive tract.

Natural killer (NK) cells are important effector lymphocytes that play a pivotal role in the innate and adaptive immune responses to tumors and viral infection. NKT cells are a heterogeneous group of T cells that share properties with both T cells and NK cells. They display immunoregulatory properties as they facilitate the cell-mediated immune response to tumors and infectious diseases, and inhibit cell-mediated immunity associated with autoimmune diseases and allograft rejection. However, the roles of NK and NKT cells in the male reproductive tract remain largely unexplored, in particular, NKT cells, tissue distribution, and state of health or disease. Infection and inflammation of the male genital tract are thought to be the primary etiological factors of male infertility. In this review, we considered this complex and rapidly growing field. We summarize the recent findings and the characterization and roles of NK and NKT cells in the male reproductive tract, including the testis, epididymis, prostate, seminal vesicle, and semen, to enhance our understanding of the immunological mechanisms of male infertility and for the design effective vaccines for male reproductive health in the future.

Difference of regulatory T cells, IL10, IL6, IFNγ, and IDO levels in female with high ASA and virgin: A research article.

OBJECTIVE: The maternal immune system requires tolerance for conception to occur. It is not only the balance of Th 1/Th2 that plays a role in pregnancy, but also the regulatory T cells (Tregs) that regulate the important role in pregnancy. One cause of failure in pregnancy is due to immunological factors, including antisperm antibodies (ASA). About 10-30% of infertile couples are caused by ASA. Th1 secretes Interferon γ (IFNγ). IFNγ is also an inducer indoleamin 2,3 dioksigenase (IDO). Cooperation between Tregs and IDO will induce tolerance for pregnancy.Th2 secretes most ofinterleukin (IL)10. Increased IL10 and decreased IL6 occur during pregnancy. The aim of this study was to analyse difference of Tregs, IL10, IL6, IFNγ, and IDO levels in female with high ASA and virgin. METHODS: Samples with high ASA were examined ASA titres using the husband's sperm auto-agglutination test (HSAaT) method.49 samples were analysed. Tregs were evaluated using flowcytometry with the human forkhead box P3 (FoxP3) staining kit of Biotech and Device.Level of IL10, IL6, and IFNγ was determined using an Abcam ELISA kit. Level of IDO was determined using an RnD ELISA kit. The data were analysed using the Mann-whitney tests. RESULTS: There are differences in the Tregs population (p = 0.000<0.05) but there is no difference IL10, IL6, IFNγ, and IDO levels in female with high ASA and virgin (p 0.140 > 0.05, p 0.680 > 0.05, p 0.204 > 0.05, and p 0.362 > 0.05). CONCLUSION: High ASA affects of the Tregs population but has no effect on cytokines IL10, IL6, IFNγ, and IDO.

Stem Cell Factor Receptor Immunoexpression in Adolescent Varicocele.

PURPOSE: Stem cell factor receptor (c-kit) plays a crucial role in regulating proliferation and survival of germ cells. The aim of this study was to find the correlation between the number of c-kit positive germ cells, testicular asymmetry and histological grade in varicocele affected testis samples of adolescents. MATERIALS AND METHODS: Twenty testicular biopsy samples of adolescents affected by varicocele and eight normal control testes were included. The relationship between percentage of testicular asymmetry, number of tubular c-kit positive germ cells and severity of spermatogenic failure was assessed. RESULTS: The mean (SD; median) histological grade for spermatogenic failure in controls was 1.37(0.52; 1), while in the varicocele group, it was 2.70(1.08; 3) (P = .0052). Mean(SD; median) number c-kit positive germ cells in the control group were 20.1(2.52; 20), while in the varicocele group it was 12.35(7.16; 12.5) (P = .0059). Spearman test documented a significant positive correlation between percentage of hypotrophy and histological grade of spermatogenic failure (r = 0.5544 , 95% CI: 0.1345 to 0.8055, P = .0112) but a negative correlation with the number of c-kit positive cells (r = - 0.5871, 95% CI: - 0.8219 to -0.1817, P = .0065). Moreover, a significant negative correlation was found between grade of histological changes and number of c-kit positive germ cells (P < .0001). CONCLUSION: A significant correlation between hypotrophy, histological lesions and c-kit positive germ cells exists in varicocele testes. This finding suggests a possible role for c-kit in the pathogenesis of germ cell impairment in varicocele. Histological changes and lack of c-kit germ cells were also noted in testes not displaying hypotrophy. We believe that reliable markers should be found as better predictors of testicular function in adolescent with varicocele.

Peptidoglycan Switches Off the TLR2-Mediated Sperm Recognition and Triggers Sperm Localization in the Bovine Endometrium.

In mammals, the uterine mucosal immune system simultaneously recognizes and reacts to most bacteria as well as allogenic sperm mainly through the Toll-like receptors (TLR)2/4 signaling pathway. Here, we characterized the impact of pathogen-derived TLR2/4 ligands (peptidoglycan (PGN)/lipopolysaccharide (LPS)) on the immune crosstalk of sperm with the bovine endometrial epithelium. The real-time PCR analysis showed that the presence of low levels of PGN, but not LPS, blocked the sperm-induced inflammatory responses in bovine endometrial epithelial cells (BEECs) in vitro. Immunoblotting analysis revealed that PGN prevented the sperm-induced phosphorylation of JNK in BEECs. Activation or blockade of the TLR2 system in the endometrial epithelium verified that TLR2 signaling acts as a commonly-shared pathway for PGN and sperm recognition. The impairment of endometrial sperm recognition, induced by PGN, subsequently inhibited sperm phagocytosis by polymorphonuclear neutrophils (PMNs). Moreover, using an ex vivo endometrial explant that more closely resembles those in vivo conditions, showed that sperm provoked a mild and reversible endometrial tissue injury and triggered PMN recruitment into uterine glands, while PGN inhibited these events. Of note, PGN markedly increased the sperm attachment to uterine glands, and relatively so in the surface epithelium. However, addition of the anti-CD44 antibody into a PGN-sperm-explant co-culture completely blocked sperm attachment into glands and surface epithelia, indicating that the CD44 adhesion molecule is involved in the PGN-triggered sperm attachment to the endometrial epithelium. Together, these findings demonstrate that, the presence of PGN residues disrupts sperm immune recognition and prevents the physiological inflammation induced by sperm in the endometrial epithelium via the MyD88-dependent pathway of TLR2 signaling, possibly leading to impairment of uterine clearance and subsequent embryo receptivity.

Three-dimensional reconstruction of leukocyte internalisation in the luminal uterine epithelium following mating.

Following mating, leukocytes are recruited to the uterine epithelium where they phagocytose spermatozoa and mediate maternal immune tolerance as well as a mild inflammatory response. In this ultrastructural study we utilised array tomography, a high-resolution volume scanning electron microscopy approach to 3D reconstruct the cellular relationships formed by leukocytes recruited to the luminal uterine epithelium 12 h post-mating in the rat. We report that following mating, neutrophils and macrophages are internalised by the luminal uterine epithelium, with multiple leukocytes internalised via contortion through a small tunnel in the apical membrane into a large membrane-bound vacuole within the cytoplasm of luminal uterine epithelial cells (UECs). Once internalised within the UECs, recruited leukocytes appear to phagocytose material within the membrane-bound vacuole and most ultimately undergo a specialised cell death, including vacuolisation and loss of membrane integrity. As these observations involve ultrastructurally normal leukocytic cells internalised within non-phagocytic epithelial cells, these observations are consistent with the formation of cell-in-cell structures via entosis, rather than phagocytic engulfment by UECs. Although cell-in-cell structures have been reported in normal and pathological conditions elsewhere, the data collected herein represents the first evidence of the formation of cell-in-cell structures within the uterine epithelium as a novel component of the maternal inflammatory response to mating.

Bovine oviduct epithelial cells suppress the phagocytic activity of neutrophils towards sperm but not for bacteria in vitro: Immunofluorescence and electron microscopic observations.

Previously, we reported that polymorphonuclear neutrophils (PMNs) are constantly existent in the bovine oviduct fluid during the pre-ovulatory stage under physiological conditions. Moreover, incubation of PMNs with bovine oviduct epithelial cells-conditioned medium (BOEC-CM) resulted in suppression of their phagocytic activity for sperm. During pathophysiological conditions, cows may be inseminated by infected semen which exposes oviductal PMNs to allogenic sperm simultaneously with pathogens. This study aimed to visually investigate the role of oviduct epithelium in regulating the phagocytic behavior of PMNs toward sperm as a physiological stimulus, with Escherichia coli (E. coli) as a pathological stimulus. In our experiment, PMNs were incubated for 2 h in BOEC-CM. Phagocytosis was then assayed by co-incubation of these PMNs either with sperm, E. coli, or latex beads. BOEC-CM significantly suppressed the direct phagocytosis of PMNs for sperm, but did not affect their phagocytic activity for E. coli or latex beads. Additionally, an investigation with scanning electron microscopy revealed that BOEC-CM suppressed the formation of DNA-based neutrophil extracellular traps (NETs) for sperm entanglement. BOEC-CM did not alter NETs formation towards E. coli. A quantification of NETs formation using an immunofluorescence microscopy showed that the areas of NETs formation for E. coli were significantly larger than those formed for sperm. Our data clearly show that the bovine oviduct, through secretions, protects sperm from phagocytosis by PMNs and eliminates bacterial dissemination through maintaining the phagocytic activity of PMNs towards bacteria.

Region-specific transcriptomic and functional signatures of mononuclear phagocytes in the epididymis.

In the epididymis, prevention of autoimmune responses against spermatozoa and simultaneous protection against pathogens is important for male fertility. We have previously shown that mononuclear phagocytes (MPs) are located either in the epididymal interstitium or in close proximity to the epithelium. In the initial segments (IS), these 'intraepithelial' MPs extend slender luminal-reaching projections between epithelial cells. In this study, we performed an in-depth characterisation of MPs isolated from IS, caput-corpus and cauda epididymis of CX3CR1EGFP+/- mice that express EGFP in these cells. Flow cytometry analysis revealed region-specific subsets of MPs that express combinations of markers traditionally described in 'dendritic cells' or 'macrophages'. RNA sequencing identified distinct transcriptomic signatures in MPs from each region and revealed specific genes involved in inflammatory and anti-inflammatory responses, phagosomal activity and antigen processing and presentation. Functional fluorescent in vivo labelling assays showed that higher percentages of CX3CR1+ MPs that captured and processed antigens were detected in the IS compared to other regions. Confocal microscopy showed that in the IS, caput and corpus, circulatory antigens were internalised and processed by interstitial and intraepithelial MPs. However, in the cauda only interstitial MPs internalised and processed antigens, while intraepithelial MPs did not take up antigens, indicating that all antigens have been captured before they reached the epithelial lining. Cauda MPs may thus confer a stronger protection against blood-borne pathogens compared to proximal regions. By identifying immunoregulatory mechanisms in the epididymis, our study may lead to new therapies for male infertility and epididymitis and identify potential targets for immunocontraception.

Zika Virus Infection, Reproductive Organ Targeting, and Semen Transmission in the Male Olive Baboon.

Zika virus (ZIKV) infection in pregnant women is a serious threat to the development and viability of the fetus. The primary mode of ZIKV transmission to humans is through mosquito bites, but sexual transmission has also been well documented in humans. However, little is known of the short- and long-term effects of ZIKV infection on the human male reproductive system. This study examines the effects of ZIKV infection on the male reproductive organs and semen and the immune response of the olive baboon (Papio anubis). Nine mature male baboons were infected with ZIKV (French Polynesian strain) subcutaneously. Six animals were euthanized at 41 days, while three animals were euthanized at 10 or 11 days postinfection (dpi). Viremia and clinical evidence of infection were present in all nine baboons. ZIKV RNA was present in the semen of five of nine baboons. ZIKV was present in the testes of two of three males euthanized at 10 or 11 dpi, but in none of six males at 41 dpi. Immunofluorescence of testes suggested the presence of ZIKV in sperm progenitor cells, macrophage penetration of seminiferous tubules, and increased tumor necrosis factor alpha (TNF-α), particularly in vascular walls. These data demonstrate that male olive baboons approximate the male human ZIKV response, including viremia, the adaptive immune response, and persistent ZIKV in semen. Although gross testicular pathology was not seen, the demonstrated breach of the testes-blood barrier and targeting of spermatogenic precursors suggest possible long-term implications in ZIKV-infected primates.IMPORTANCE Zika virus (ZIKV) is an emerging flavivirus spread through mosquitoes and sexual contact. ZIKV infection during pregnancy can lead to severe fetal outcomes, including miscarriage, fetal death, preterm birth, intrauterine growth restriction, and fetal microcephaly, collectively known as congenital Zika syndrome. Therefore, it is important to understand how this virus spreads, as well as the resulting pathogenesis in translational animal models that faithfully mimic ZIKV infection in humans. Such models will contribute to the future development of efficient therapeutics and prevention mechanisms. Through our previous work in olive baboons, we developed a nonhuman primate model that is permissive to ZIKV infection and transfers the virus vertically from mother to fetus, modeling human observations. The present study contributes to understanding of ZIKV infection in male baboon reproductive tissues and begins to elucidate how this may affect fertility, reproductive capacity, and sexual transmission of the virus.

Ovulatory follicular fluid induces sperm phagocytosis by neutrophils, but oviductal fluid around oestrus suppresses its inflammatory effect in the buffalo oviduct in vitro.

We have recently shown that the conditioned media from bovine oviductal epithelial cell culture suppress sperm phagocytosis by neutrophils, suggesting that the oviduct around oestrus supplies the anti-inflammatory microenvironment. To investigate the immune response of neutrophils toward the sperm at ovulation in the buffalo oviduct, we examined (a) a detailed distribution of neutrophils in the oviduct in buffaloes, (b) the effect of ovulatory follicular fluid (FF) and oviductal fluid (OF) on sperm phagocytosis by neutrophils, and (c) the interaction of the ovulatory FF with OF on sperm phagocytosis by neutrophils in vitro. Buffalo oviducts were collected from healthy reproductive tracts at a local slaughterhouse. A detailed observation by histological examination and transmission electron microscopy revealed that neutrophils exist in the oviduct epithelium and lumen throughout the oestrous cycle in buffaloes. The number of neutrophils at the oestrus stage was higher in ampulla compared with those in isthmus, whereas they remained relatively constant at the dioestrus stage. Two hours of preincubation of neutrophils with FF enhanced sperm phagocytosis through the formation of neutrophil extracellular traps (NETs) together with H2 O2 production, whereas OF around oestrus (eOF) suppressed sperm phagocytosis, NETs formation, and H2 O2 production and relieved the above FF-induced inflammatory response. Our findings show that neutrophils exist in the healthy cyclic oviduct across bovine species, and the OF supplies a strong anti-inflammatory environment that could minimize the inflammatory effect of the FF that flows into the oviduct lumen after ovulation and supports the occurrence of fertilization.

Epithelial dynamics in the epididymis: role in the maturation, protection, and storage of spermatozoa.

Epithelial cells line the lumen of tubular organs and are key players in their respective functions. They establish a unique luminal environment by providing a protective barrier and by performing vectorial transport of ions, nutrients, solutes, proteins, and water. Complex intercellular communication networks, specific for each organ, ensure their interaction with adjacent epithelial and non-epithelial cells, allowing them to respond to and modulate their immediate environment. In the epididymis, several epithelial cell types work in a concerted manner to establish a luminal acidic milieu that is essential for the post-testicular maturation and storage of spermatozoa. The epididymis also prevents autoimmune responses against auto-antigenic spermatozoa, while ensuring protection against ascending and blood pathogens. This is achieved by a network of immune cells that are in close contact and interact with epithelial cells. This review highlights the coordinated interactions between spermatozoa, basal cells, principal cells, narrow cells, clear cells, and immune cells that contribute to the maturation, protection, selection, and storage of spermatozoa in the lumen of the epididymis.

The epididymal immune balance: a key to preserving male fertility.

Up to 15% of male infertility has an immunological origin, either due to repetitive infections or to autoimmune responses mainly affecting the epididymis, prostate, and testis. Clinical observations and epidemiological data clearly contradict the idea that the testis confers immune protection to the whole male genital tract. As a consequence, the epididymis, in which posttesticular spermatozoa mature and are stored, has raised some interest in recent years when it comes to its immune mechanisms. Indeed, sperm cells are produced at puberty, long after the establishment of self-tolerance, and they possess unique surface proteins that cannot be recognized as self. These are potential targets of the immune system, with the risk of inducing autoantibodies and consequently male infertility. Epididymal immunity is based on a finely tuned equilibrium between efficient immune responses to pathogens and strong tolerance to sperm cells. These processes rely on incompletely described molecules and cell types. This review compiles recent studies focusing on the immune cell types populating the epididymis, and proposes hypothetical models of the organization of epididymal immunity with a special emphasis on the immune response, while also discussing important aspects of the epididymal immune regulation such as tolerance and tumour control.