Receptor from Streptococcus pyogenes as a potential antidote against sperm immobilization factor-induced sperm impairment and infertility.

The present study was undertaken to demonstrate the existence of mimicry between spermatozoa and bacteria. For this, the shared antigenic determinants between mouse spermatozoa and Streptococcus pyogenes against a common ligand, sperm immobilization factor (SIF), were isolated. The mimicry was established on the basis of their ability to ameliorate the SIF-mediated compromised sperm parameters in vitro viz. motility, viability, morphology and Mg2+-ATPase activity of spermatozoa. Further, both the receptors i.e. SIF-binding receptor from mouse spermatozoa (MS-SBR) and SIF-binding receptor from S. pyogenes (S-SBR) were able to block the binding of FITC-labelled SIF to spermatozoa and bacteria. The in vivo studies also showed that MS-SBR (10 µg)/S-SBR (25 µg) could alleviate SIF-induced infertility in female BALB/c mice, further providing evidence for molecular similarities between bacteria and spermatozoa.

Amelioration of sperm immobilisation factor-induced infertility by bacterial antigenic determinants cross-reacting with spermatozoa.

A strain of Staphylococcus aureus, capable of invitro immobilisation of human and mouse spermatozoa, was already present in our laboratory. Therefore, in the present study, the factor responsible (sperm immobilisation factor, SIF) was isolated and purified. It was found to compromise not only motility, but also viability, morphology and Mg2+-ATPase activity of mouse spermatozoa. Also, SIF (250µgmL-1), when administered intravaginally in female BALB/c mice before mating, showed 100% contraceptive effect. Moreover, fluorescein isothiocyanate-labelled SIF was also found to bind mouse spermatozoa and various motile as well as non-motile bacteria, indicating the presence of common SIF-binding receptors on spermatozoa and bacteria. Further, to demonstrate molecular mimicry, the amelioration of SIF-induced impairment of sperm function by a SIF-binding bacterial receptor was compelling. For this, the SIF-binding receptor from Escherichia coli (E-SBR) was purified and evaluated for its ameliorative effect on SIF-induced sperm impairment invitro and invivo. Interestingly, upon the addition of mouse spermatozoa to SIF pre-incubated with E-SBR, an ameliorative effect against SIF-induced impairment of sperm function could be observed through analysis of normal sperm parameters (motility, viability, morphology, Mg2+-dependent ATPase levels). E-SBR also blocked binding of labelled SIF to spermatozoa and bacteria and alleviated SIF-induced infertility in female BALB/c mice. This provided evidence for molecular similarities between bacteria and spermatozoa, owing to which anti-bacterial antibodies cross-reacting with spermatozoa might be produced and infertility might follow.

Human sperm immobilizing activity of aminophenyl arsenic acid and its N-substituted quinazoline, pyrimidine, and purine derivatives: protective effect of glutathione.

We examined the potential toxicity of pentavalent organic arsenicals for human sperm. We used computer-assisted sperm analysis to examine the effects of three aminophenyl arsenicals and their nine N-substituted quinazoline, pyrimidine, and purine derivatives on human sperm motility and kinematics in human semen and medium. Among the arsenicals examined, (aminophenylazo)-phenyl arsonic acid and its N-substituted pyrimidine derivative PHI-370 (2-methylthio-4-[(4'-aminophenylazo)-phenylarsonic acid] pyrimidine) exhibited rapid sperm immobilizing activity in medium with EC(50) values of 77 and 82 microM, respectively, and t(1/2) of < 3 min. Molecular modeling analysis indicated that sperm-immobilizing organic arsenicals exhibit high dipole moments (>7 Debyes). Sperm immobilizing activity of these arsenicals was completely abrogated in the presence of seminal plasma. Furthermore, coincubation of motile sperm with PHI-370 in the presence of reduced glutathione (GSH) resulted in dose-dependent protection of sperm motility and sperm motion parameters. Coincubation of the arsenical with GSH at a molar ratio of 1:20 resulted in 95% retention of sperm progressive motility. The mean values of the other sperm movement characteristics also showed > 90% protection. These observations suggest that the rapid sperm immobilizing activity of these pentavalent arsenicals may be as a result of direct binding of the arsenical with the sperm thiol components essential for sperm motility as well as induction of oxidative damage by disruption of sperm cell's antioxidant system. Sodium arsanilate and its N-substituted pyrimidine derivative, PHI-370, are useful probes to further evaluate the mechanism of pentavalent arsanilate-induced human sperm dysfunction.

Hormonal protection from cyclophosphamide-induced inactivation of rat stem spermatogonia.

Studies of protection of testicular function from cyclophosphamide with hormonal pretreatment have been limited by the lack of a convenient model for cyclophosphamide-induced inactivation of stem spermatogonia. In the rat, the mortality from cyclophosphamide had prevented the administration of sufficient dosages to produce detectible damage to stem spermatogonia. To overcome this problem, we used bone marrow transplantation and sodium 2-mercaptoethanesulfonate (Mesna) treatment to raise the lethal dose for 50% of the animals (LD50) for cyclophosphamide from 275 to > 400 mg/kg body weight. In addition we used irradiation, 2 weeks prior to injection of cyclophosphamide, to greatly enhance the measured toxicity of cyclophosphamide towards stem spermatogonia. Whereas sperm counts at 9 weeks after a 300 mg/kg cyclophosphamide dose were reduced by only a factor of 1.6 without prior irradiation, they were reduced by a factor of 60 when 2.5 Gy of irradiation had been given. Dramatic protection against this toxicity was produced by hormone treatment with a gonadotropin-releasing hormone (GnRH) antagonist (Nal-Glu) and an antiandrogen (flutamide) following the radiation but prior to cyclophosphamide. This hormone treatment did not modify the stem cell toxicity of the radiation and it therefore must be protecting stem cells against cyclophosphamide-induced damage. Because GnRH antagonist-antiandrogen treatment can protect stem spermatogonial survival and/or function in the rat from cyclophosphamide-induced damage, if the same principles are applicable in human, hormonal pretreatment should be useful for preventing the prolonged azoospermia caused by chemotherapy with cyclophosphamide-containing protocols.

The zoapatle. VI. Revisited.

A review of new Zoapatle publications was made, including five chemical compounds characterized recently. Relative potency of Kaurenoic acid, Kauradienoic acid (its mixture), Zoapatanol and Montanol was estimated in an in vitro guinea pig uterine assay. Kaurene compounds were several times more potent than Montanol and Zoapatanol as uteroactive substances. Zoapatle aqueous crude extract made from Montanoa frutescens had a strong in vitro uterine potency and unique in vivo characteristics in several biological systems, described in detail in the following five publications.

Sperm autoantibodies as a consequence of vasectomy. II. Long-term follow-up studies.

Thirty-four out of fifty-two vasectomized men studied previously were studied again about 5 years after vasectomy for sperm-agglutinating and sperm-immoblizing antibodies, and for antibodies to human protamine. Only one man lost his already weak antibody activity, whilst one out of eight men, negative at 1 year, appeared to be positive at 5 years. Slightly higher titres in one of the three sperm antibody tests were found in the sera of about 30% of the men. Only in three (9%) was there a rise of two or more steps in more than one technique. Agglutinins and immobilizins were shown to be strongly correlated, as was the case with antibodies to human protamine and head-to-head agglutinins. Seminal plasma sperm agglutinins were detected in the samples of only four (out of thirty) men, in low titres. Circulating immune complexes tested with various techniques were only found in a few sera and not consistently. This prolonged study shows that sperm autoantibodies formed within 1 year after vasectomy are persistent. Their role in remaining infertility after reanastomosis requires further study.

PIP: 34 of 52 men who had participated in a previous study of the occurrence of sperm antibodies 1 year after a vasectomy donated blood again 5 years later; from 30 of them a seminal plasma sample was also tested. Serum samples were investigated as well for the presence of circulating immune complexes, based on findings in experimental animal models. The antibodies tested for were sperm-agglutinating, sperm-immobilizing, and antibody to human protamine. To obtain an optimal comparison in the 1 year and 5-year postvasectomy serum samples, both samples were titrated at the same time with the same donor semen sample. Declines of antibody titers were rarely found between the 2 specimens. 1 patient lost an already weak antibody activity; in 1 man the agglutinin but not the immobilizin titer decreased 2 steps; and in 2 others the immobilizin titer decreased 2-3 steps without change in agglutinin titer. A few titer rises were seen. Of the 8 men with no agglutinins at 1 year, only 1 developed them later, and of the 22 patients having no immobilizin titer at 1 year, 5 had them at 5 years. Overall, slightly higher titers in 1 of the 3 sperm antibody tests were found in the sera of about 30% of the men. Agglutinins and immobilizins were strongly correlated, as were antibodies to human protamine and head-to-head agglutinins. Seminal plasma sperm agglutinins were detected in the samples of only 4 of 30 men, in low titers. Circulating immune complexes tested with various techniques were found in only a few sera and then inconsistently. It is concluded that sperm antibodies formed postvasectomy are persistent.

Artificial insemination with spermatozoa in formaldehyde.

The ability of formaldehyde to preserve the integrity of the membranes of spermatozoa, as indicated by eosin staining (Dott & Foster, 1975), prompted an investigation to discover what other properties of spermatozoa were preserved by low concentrations of formaldehyde in vitro. In a series of experiments on bull, ram and boar spermatozoa it has been shown that spermatozoa rendered immotile by formaldehyde recovered their motility when the formaldehyde was removed by washing up to 12 hr afterwards (H.M. Dott & G.C. Foster, unpublished). To find out if fertility was preserved ewes and sows were inseminated with spermatozoa rendered immotile with formaldehyde.

[Action of different components of the kallikrein kinin-system on sperm motility in vitro (author's transl)]. / Wirkungen von verschiedenen Komponenten des Kallikrein-Kinin-Systems auf die Spermatozoen-Motilität in vitro

In vitro experiments with human semen showed a significant increase of quantitative and qualitative sperm motility after addition of kallikrein at concentrations of 1 KU/ml. Stimulation of sperm motility was further increased and extended by addition of human serum as a source of kininogen. Kinins added directly also showed enhancement of sperm motility. In contrast, carboxypeptidase B, a kininase, significantly reduced sperm motility. The physiological and therapeutical aspects of these results are discussed.