Regulation of human B cell proliferation and differentiation by seminal plasma

Effect of seminal plasma on dendritic cell differentiation in vitro depends on the serum source in the culture medium

Dendritic cells (DCs) are key in shaping immune responses and are recruited to the human cervix after coitus by seminal plasma (SP). SP has been shown to skew the differentiation of monocyte-derived DCs towards an anti-inflammatory profile when cultured in medium containing fetal calf serum (FCS). Here, we confirmed that SP skewed DCs cultured in fetal bovine serum (FBS) towards a tolerogenic profile. To create a setting more similar to the in vivo situations in humans, we tested the immune regulatory effect of SP on DCs in cell cultures containing human serum (HS). SP-DCs cultured in HS did show increased CD14 and decreased CD1a, indicating an inhibited maturation phenotype. Gene expression of TGF-β and IL-10 and IL-10 protein expression were elevated in LPS-activated SP-DCs, whereas IL-12p70 protein levels were decreased compared to LPS-activated control DCs. In contrast to FBS culture conditions, in the presence of HS co-cultures of SP-DCs with allogeneic peripheral blood mononuclear cells (PBMCs) did not result in decreased T cell proliferation and inflammatory cytokine production. Thus, under HS culture conditions SP can skew the differentiation of monocyte-derived DCs phenotypically towards alternatively activated DCs, but this immune regulatory phenotype is functionally less pronounced compared to SP-treated DCs cultured in FBS containing medium. These findings highlight the importance of the source of the serum that is used in SP treated cell cultures in vitro.

Heterogeneous pathways of maternal-fetal transmission of human viruses (review)

Several viruses can pass the maternal-fetal barrier, and cause diseases of the fetus or the newborn. Recently, however, it became obvious, that viruses may invade fetal cells and organs through different routes without acute consequences. Spermatozoa, seminal fluid and lymphocytes in the sperm may transfer viruses into the human zygotes. Viruses were shown to be integrated into human chromosomes and transferred into fetal tissues. The regular maternal-fetal transport of maternal cells has also been discovered. This transport might implicate that lymphotropic viruses can be released into the fetal organs following cellular invasion. It has been shown that many viruses may replicate in human trophoblasts and syncytiotrophoblast cells thus passing the barrier of the maternal-fetal interface. The transport of viral immunocomplexes had also been suggested, and the possibility has been put forward that even anti-idiotypes mimicking viral epitopes might be transferred by natural mechanisms into the fetal plasma, in spite of the selective mechanisms of apical to basolateral transcytosis in syncytiotrophoblast and basolateral to apical transcytosis in fetal capillary endothelium. The mechanisms of maternal-fetal transcytosis seem to be different of those observed in differentiated cells and tissue cultures. Membrane fusion and lipid rafts of high cholesterol content are probably the main requirements of fetal transcytosis. The long term presence of viruses in fetal tissues and their interactions with the fetal immune system might result in post partum consequences as far as increased risk of the development of malignancies and chronic pathologic conditions are discussed.

Viruses in the mammalian male genital tract and their effects on the reproductive system

This review describes the various viruses identified in the semen and reproductive tracts of mammals (including humans), their distribution in tissues and fluids, their possible cell targets, and the functional consequences of their infectivity on the reproductive and endocrine systems. The consequences of these viral infections on the reproductive tract and semen can be extremely serious in terms of organ integrity, development of pathological and cancerous processes, and transmission of diseases. Furthermore, of essential importance is the fact that viral infection of the testicular cells may result not only in changes in testicular function, a serious risk for the fertility and general health of the individual (such as a fall in testosteronemia leading to cachexia), but also in the possible transmission of virus-induced mutations to subsequent generations. In addition to providing an exhaustive account of the data available in these domains, this review focuses attention on the fact that the interface between endocrinology and virology has so far been poorly explored, particularly when major health, social and economical problems are posed. Our conclusions highlight the research strategies that need to be developed. Progress in all these domains is essential for the development of new treatment strategies to eradicate viruses and to correct the virus-induced dysfunction of the endocrine system.

Distinct expression of cytokines and mitogenic inhibitory factors in semen of fertile and infertile men

PROBLEM

To assess the effect of seminal plasma (SP) of fertile and infertile men on leukocyte mitogenic response, and the capability of sperm cells to produce IL-1.

METHODS

This study included four groups: fertile men (donors, normal), infertile men with azoospermia (azoo), oligo-terato-asthenozoospermia (OTA), and OTA with genital infection (OTA-inf). Mouse spleen cell proliferation in response to lipopolysaccharide (LPS) or Concanavalin-A (Con-A) was examined in the presence of SP from the above four groups. Supernatants (sup) and lysates (lys) of sperm cells from fertile and oligoteratoasthenospermic (OTA) men were evaluated for IL-1 bioactivity by specific bioassay.

RESULTS

Seminal plasma (SP) of the four groups were shown to inhibit the mitogenic response of mouse spleen cells to LPS and Con-A. SP of fertile men was significantly more inhibitory than SP from infertile men. Sperm cells from fertile and OTA infertile men constitutively produced IL-1. Sperm cells of both groups produced similar levels of IL-1 as examined in the supernatants and lysates.

CONCLUSIONS

Seminal plasma of fertile men had more inhibitory mitogenic activity than that of OTA. Sperm cells constitutively produce IL-1. It is possible that the factors involved in this inhibition are not only anti-proliferative immune factors. Cytokines and inhibitory factors of mitogenesis in the seminal plasma may be involved in the physiology and pathophysiology of sperm functions and thus affect male fertility.

Anti-seminal plasma antibodies associated with infertility: I. Serum antibodies against normozoospermic seminal plasma in patients with unexplained infertility

PROBLEM

To determine whether patients whose infertility remains unexplained (by routine physical and laboratory investigations including sperm antibody testing) exhibits significantly elevated humoral anti-seminal plasma immune responses in comparison to fertile individuals.

METHOD

Sera from 72 infertile couples were examine by ELISA for the presence of antibodies against normozoospermic seminal plasma (NSP). A group of 36 fertile individuals was used to determine the level of physiological reactivity. Kibrick's and Friberg's sperm-agglutination tests were employed to distinguish patients routinely diagnosed as immunologically infertile.

RESULTS

Anti-NSP reactivity was elevated in 18% of male and 26% of female patients. In the female patients, the prevalence rate for elevated anti-NSP reactivity was significantly higher among partners of positive men. In only 4% the positive anti-NSP results coincided with sperm-agglutinating antibodies.

CONCLUSION

NSP constituents other than sperm-coating antigens might interfere with infertility related autoimmune imbalance. The identification of the corresponding NSP antigens might help to resolve more cases of unexplained infertility.

Anti-seminal plasma antibodies associated with infertility: II. Comparative investigation of human antibody binding to normo-, astheno-, and azoospermic seminal plasma antigens

PROBLEM

Sera from infertile patients with elevated reactivity against normozoospermic seminal plasma (NSP) have been selected to investigate human antibody binding to seminal fluid antigens present in abnormal ejaculates.

METHOD

Sera from 32 idiopathically infertile patients and 44 control sera from fertile individuals were examined by ELISA against: 1) pooled seminal plasma from asthenozoospermic ejaculates (AsthSP), 2) pooled seminal plasma from patients with aspermatogenic azoospermia (AzooSP), and 3) chromatographic fractions from NSP, AsthSP and AzooSP.

RESULTS

Of 32 patients positive for anti-NSP antibodies, only four exhibited increased reactivity to whole AsthSP and/or AzooSP, while 14 recognized antigens of different Mr and various distributions in the corresponding chromatographic fractions.

CONCLUSION

Targets of human anti-NSP antibodies might be lacking, less concentrated, and/or modified in AsthSP and AzooSP. These findings suggest their physiological importance and the possible relevance of the observed auto- and iso-immune responses to infertility.

Inflammatory response in the pig uterus induced by seminal plasma

The immunological and physiological influence of seminal plasma on the local uterine environment was investigated by immunohistochemical and flow cytometrical studies on uterine tissues and lymph nodes taken from gilts after mating with a vasectomised boar and from control, unmated gilts. These studies revealed that mating with a vasectomised boar induces an acute transient inflammatory response in the endometrium resulting in marked changes in the presence and distribution of leukocytes and extensive proliferation of the endometrial glands. At the same time there was an increase in CD8L and sIg+ cells and an up-regulation of MHC class II and IL-2 receptor expression in the uterine lymph nodes of mated pigs. This would suggest that seminal plasma deposited in the uterus can activate cells in the local draining lymph nodes. Together, these results demonstrate in utero that pronounced immunological and physiological changes are induced in vivo by seminal plasma.