Engineering tetravalent IgGs with enhanced agglutination potencies for trapping vigorously motile sperm in mucin matrix

Multivalent antibodies such as sIgA can crosslink motile entities such as sperm and bacteria, creating agglomerates that are too large to permeate the dense mucin matrix in mucus, a process commonly referred to as immune exclusion. Unfortunately, sIgA remains challenging to produce in large quantities, and easily aggregates, which prevented their use in clinical applications. To develop sIgA-like tetravalent antibodies that are stable and can be easily produced in large quantities, we designed two IgGs possessing 4 identical Fab domains, with the Fabs arranged either in serial or in the diametrically opposite orientation. As a proof-of-concept, we engineered these tetravalent IgG constructs to bind a ubiquitous sperm antigen using a Fab previously isolated from an immune infertile woman. Both constructs possess at least 4-fold greater agglutination potency and induced much more rapid sperm agglutination than the parent IgG, while exhibiting comparable production yields and identical thermostability as the parent IgG. These tetravalent IgGs offer promise for non-hormonal contraception and underscores the multimerization of IgG as a promising strategy to enhance antibody effector functions based on immune exclusion.

Colonization of mouse vagina with Pseudomonas aeruginosa: A plausible explanation for infertility

Little attention has been paid to the influence of asymptomatic colonizers of genital tract on female infertility. Albeit, a variety of uropathogens have been known to negatively alter sperm parameters in vitro, but their impact on female fertility outcome under in vivo conditions is not clearly established. Therefore, the present study was intended to investigate the effect of Pseudomonas aeruginosa on sperm parameters and to identify its role in female infertility. The strain of P. aeruginosa was found to reduce sperm motility, viability and sperm Mg⁺⁺ATPase activity. It could also lead to premature acrosomal loss and induce morphological defect in spermatozoa. For fertility studies, female mice administered intravaginally with 10⁴, 10⁶, 10⁸ cfu of P. aeruginosa for 10 consecutive days, were allowed to mate with proven breeder male on day 12. The results showed that group of mice receiving P. aeruginosa were rendered infertile whereas group receiving PBS showed abdominal distension, string of pearls and finally delivered pups at the end of gestation period. Further, no other clinical manifestation could be observed apparently, histologically or immunologically. Thus, it can be concluded that infertility in mice might be attributed to asymptomatic colonization of genital tract with sperm immobilizing P. aeruginosa.

Safety studies of sperm agglutinating factor produced by Staphylococcus aureus as a vaginal contraceptive: in vivo studies

Sperm agglutinating factor (SAF) isolated from Staphylococcus aureus when applied at concentration 10 μg before mating completely prevented conception in the mouse. The objective of the present study was to evaluate its safety, as safety is an important concern to be addressed before a compound is selected for contraceptive use. Our results showed that SAF has a very high safety profile. Vaginal application of SAF at 10 μg to the mouse for 14 consecutive days caused no systemic toxicity and vaginal irritation as indicated by lack of effect on organ weights and histology. Moreover, no adverse effect was observed on the subsequent reproductive capability, perinatal outcome and growth and development of the offspring. SAF (10 μg) did not irritate the skin or penile mucosa. Oral administration of 2 mg/kg body weight of SAF did not show any toxicity to reproductive and non-reproductive organs. Therefore, SAF with spermicidal activity and lack of toxicity may have the potential to become the active ingredient of a vaginal contraceptive.

Serum Agglutinating and Immobilising Sperm Antibodies in Men Attending a Sexually Transmitted Diseases Clinic

The tray slide agglutination test (TAT) and micro immobilisation test (MIT) to detect antisperm antibodies were carried out on serum samples from 217 men attending a clinic for sexually transmitted diseases (STD), 151 fertile men requesting vasectomy and 645 men with a marriage with primary infertility. There was no difference in results between the fertile men and the men attending the clinic for sexually transmitted diseases although both sets of results differ from those of the infertile men. These results make it unlikely that venereal disease will trigger antisperm antibody production.

Immunologic and testicular response in guinea pigs after unilateral traumatic orchitis

An acute and intense trauma was inflicted in one of the testes of adult guinea pigs. The immunological response and histological changes developed both in the injured and contralateral glands were studied at different intervals of time. It was observed: 1) Necrotic seminiferous tubules and a granulomatous cell reaction were seen in the injured gonad at 15 days. This was followed by a reduction of the mononuclear cell infiltration at 48 days. Finally a fibrotic tissue replaced the damaged areas at around 100 days. 2) Foci showing the classical picture of immunologic orchitis appeared in the contralateral gland at 15 and 48 days. Less frequent lesions were detected in the final period of the experiment. 3) These lesions were accompanied by cellular immunity detectable by the macrophage migration inhibition test at 15 and 48 days. With the exception of cytophilic activity also detected in same periods, no antibodies of hemagglutinating and sperm-agglutinating types could be found.

Experimental findings with spermantibodies: condom therapy (a case report)

A couple with no demonstrable cause for their infertility, except for a pronounced antisperm activity in the blood serum of the female partner, were instructed to use a condom while our laboratory monitored the wifes antibody titer. The antibody activity declined sufficiently and an artificial husband insemination were performed after seven months of therapy. A precise report of the spermantibody activity over an eleven month period are given by the authors.

Serum sperm antibodies in cases of azoospermia: comparative diagnostic value of separate and combined, agglutination, immoblization and cytotoxic serological tests

To study the diagnostic value of various serological tests in the detection of serum sperm antibodies a group of 50 patients with azoospermia was studied. Cases were divided by testicular biopsy into: 32 obstructive and 16 non obstructive cases. Tests applied included a microagglutination and a macroagglutination test as well as 2 complement dependent tests; a sperm cytotoxic and a sperm immobilization tests. Applied separately the macroagglutination was the most sensitive test but used together, more cases were detected. Because of this and the different value and significance of each test, it is advisable to use more than one test in the investigations of cases of male infertility.

Seminal factor VII and factor VIIa: supporting evidence for the presence of an active tissue factor-dependent coagulation pathway in human semen

Human semen spontaneously coagulates into a semisolid mass and then wholly liquefies in a process that may have some similarity to that of normal blood. This well described phenomenon is referred to as coagulation and liquefaction of semen. Besides other active components of the haemostatic system, semen contains a significant amount of functional tissue factor (TF). However, TF needs factor (F)VII in order to exert it actions. In this study, we assessed human semen for the presence of FVII and FVIIa, and related their levels to conventional fertility parameters. Using a functional, one stage, clotting assay based upon the prolongation of the prothrombin clotting time, using the ACL 300R analyser and an Imubind FVIIa ELISA assay, FVII and FVIIa levels were measured in 97 semen specimens obtained from sub-fertile (sperm counts <20 x 10(6)/mL), normally fertile (sperm counts >or=20 x 10(6) but <60 x 10(6)/mL), fertile sperm donors (sperm counts >or=60 x 10(6)/mL), vasectomized subjects and in a pooled normal semen parameters group (categorization into groups was based on the World Health Organization guidelines on fertility criteria). In addition, conventional semen parameters were analysed on all semen samples. Both FVII and FVIIa were quantifiable in human semen. The mean levels of FVII and FVIIa were 4.4 IU/dL and 12 ng/mL respectively. Despite the observed variations of FVIIa levels in the studied groups they did not meet statistical significance when the groups were tested against each other. However, seminal FVIIa levels showed a significant positive association with semen liquefaction time, sperm motility and semen volume. The anti-sperm antibodies and sperm-agglutination groups were also associated with raised seminal FVIIa levels. We observed no significant relationship between FVIIa levels and total sperm concentration, sperm count per mL (sperm density), sperm progression and days of sexual abstinence. This study demonstrates that human semen contains appreciable amounts of FVII and FVIIa. It is possible to quantify these using commercially available assays. There also appears to be a direct correlation between the levels of these factors and certain seminal parameters. This finding reinforces the concept of an active clotting system in human semen, by establishing the missing link in the activation of a TF-dependent pathway.

Semen quality and sperm functional parameters in fertile Indian men

The reports of a decline in the reproductive health of men worldwide prompted the present study to be undertaken so that baseline semen parameters could be established in Indian men. Semen profile and sperm function parameters were evaluated in 368 Indian men of proven fertility, settled in Delhi. The results of the study were compared with available published information from Indian men. The mean sperm concentration and semen volumes were 68.22 +/- 15.14 x 10(6) ml(-1) and 3.20 +/- 0.94 ml, respectively. Rapid, linear progressive motility and sluggish linear motility were 40.95 +/- 9.15% and 24.95 +/- 7.01%, respectively. A comparison of the results of the present study with earlier published data did not support the contention of a decrease in the semen quality in Indian men.

[Electrophoretic analysis (SDS PAGE) of ovulatory cervical mucus in patients with fertility failure and after unsuccessful IVF]

OBJECTIVE

To evaluate the presence and activity of local sperm antibodies and electrophoretic analysis of ovulatory cervical mucus (OCM) to prove the correlation of results of Kremer mucus sperm capillary penetration test and i-MAR (mixed antiimmunoglobulin reaction) test with SDS-PAGE.

DESIGN

Retrospective study.

SETTING

Department of Obstetrics and Gynecology, Medical Faculty of Charles University, Pilsen.

METHODS

94 patients aged 22-40 (average age 32.3 years) were chosen for our study. Ovulatory cervical mucus was taken from uterine cervical canal in Consultation for Reproductive Immunology. Kremer test and indirect mixed antiglobulin reaction test for IgG, IgA, IgM and IgE were used for detection of sperm antibodies. For the SDS-PAGE analysis, OCM was incubated with sodium dodecyl sulfate. We studied separated protein fractions from OCM.

RESULTS

Sperm-capillary ovulatory mucus penetration test (Kremer) was 0-10 cm/hour in our group (average value in patiens without sperm antibodies was 2.43 cm/hour, with sperm agglutinating antibodies 1.4 cm/hour), significant levels (> 45%) of spermagglutinating antibodies were detected in IgA in 6 patients (6.38%), IgG in 5 (5.32%) patients, sperm-cytotoxic levels (IgA and/or IgG) in 5 patients (5.32%); levels of IgE less than 30% in 3 patients (3.19%). Individual immunological factors gained by SDS-PAGE showed the spectrum of various molecular weights with range of 14.4- 350 kDa. The presence of IgG and/or IgA was in 53 cases (56.38%), with 13 ASA positivities (24.53% correlation with i-MAR test) and no ASA activity in 40 cases (75.47%); 6 ASA positive patiens (31.58%) were not detected by SDS-PAGE.

CONCLUSIONS

Analysis of 94 OCM by SDS-PAGE showed several significant correlates, but their specifications will be based on further immunoblot research.

Molecular Cloning, Expression of Testicular Transcript Abundant in Germ Cells and Immunobiological Effects of the Recombinant Protein

PROBLEM

It has been well documented that antisperm antibodies can be causative factors for infertility. In this report we have identified a protein on human sperm referred as human sperm-associated protein (HSAP) using serum of an immunoinfertile woman; it is thus a sperm-specific protein--a candidate molecule for control of fertility.

METHOD OF STUDY

An immunoinfertile woman serum showing head-head sperm agglutination and acrosomal localization, reacted with human sperm protein of apparent molecular weight of 48 kDa on Western blot. Anti-48 kDa antiserum was raised in rabbit by eluting 48 kDa protein and was used to screen the human testis cDNA expression library. A putative positive hsap cDNA clone was obtained, sequenced and subjected to tissue specificities studies by Northern blotting. The cell type-specific expression was done using in situ RNA hybridization studies. To obtain recombinant HSAP (r-HSAP), hsap cDNA was cloned in pET 22b(+) expression vector. r-HSAP was expressed as polyhistidine fusion protein in Escherichia coli and purified. Rabbits were immunized with the purified r-HSAP, which led to generation of antibodies. In order to evaluate in vitro immunocontraceptive potential, the anti-r-HSAP antibodies were characterized by agglutination assay, zona-free hamster egg penetration assay, indirect immunofluorescence (IIF) assay, and by flow cytometry analysis.

RESULTS

We have cloned a human testis gene encoding a protein (HSAP) of 328 amino acids. Antibodies against the purified recombinant protein specifically recognized approximately 40 kDa r-HSAP, and a cognate 48 kDa protein band in human sperm extract in Western blot procedure. The anti-r-HSAP antibodies localized acrosomal compartment, inhibited sperm binding/attachment in zona-free hamster penetration assay and revealed surface binding with human live sperm by flow cytometry. The cDNA sequence has been submitted to EMBL and has been given the accession number Y16676.

CONCLUSION

This study has put in evidence that novel sperm-specific r-HSAP has role in sperm function and may have application in the development of a contraceptive vaccine. The availability of the recombinant protein will facilitate studies on the assessment of its potential as a contraceptive immunogen.

[Significance of determination of intra-acrosomal proteins and sperm antibodies in human reproduction]

OBJECTIVE

Comparison of the positive intra-acrosomal proteins and spermagglutinating antibodies in human semen samples from various groups of patients.

DESIGN

Prospective study.

SETTING

Department of Gynecology and Obstetrics and Faculty Hospital, Charles University, Pilsen, Institute of Molecular Genetics, Czech Academy of Science, Prague.

METHODS

Monoclonal antibodies Hs-8 and Hs-14 (prepared in the Institute of Molecular Genetics, Prague) were used for detection of intra-acrosomal sperm proteins. Microscopic immunofluorescent methods detected the incidence, the character and the percentage of the spermatozoa specified by above-mentioned monoclonal antibodies. Direct mixed anti-immunoglobulin reactions test (MAR-test) for IgG, IgM, IgA, IgE was used for detection of spermagglutinating antibody. We examined 315 infertile patients from Special Consultation for Immunology of Reproduction and from the IVF programme, and sperm healthy donors (January 2002-March 2003).

RESULTS

Native donor's sperm cells had excellent positive intra-acrosomal proteins stained with monoclonal antibodies Hs8 and Hs14 and after thawing as well as. No spermagglutinating antibodies were found. In the group with normal sperm count and light microscopic morphology we found the presence of seminal spermagglutinating antibodies in 11% (IgG), in 14.5% (IgA), in 3.6% (IgM), in 5.2% (IgE). Significant positivity of intra-acrosomal protein stained with Hs8 monoclonal antibody was reached in 68.4%, and with Hs14 monoclonal antibody in even 81.3% of men. On the other hand, in oligoasthenospermatic patients we found significant increasing of spermagglutinating antibodies (for IgG 40.5%, for IgA 28.6%, for IgM 9.5%, for IgE 11.9%). Dominant good staining of intra-acrosomal proteins were seen only in 15.5% of men (for Hs8) and in 20.2% (for Hs14).

CONCLUSION

The quantitative detection of intra-acrosomal sperm proteins and spermagglutinating antibodies are used as important properties of human semen and serve for evaluation of acrosomal state, and male fertility together.

Sequence of ejaculation affects the spermatozoon as a carrier and its message

It is a widespread misunderstanding that the human ejaculation produces a homogeneous fluid with constant environment for the spermatozoa. On the contrary, spermatozoa are mainly expelled together with the zinc-rich prostatic fluid in the first ejaculation fractions. In nature, these spermatozoa most likely enter the cervical mucus before any significant contact with the later, sperm hostile fractions takes place. Spermatozoa collected in the laboratory for diagnosis, treatment or research purposes face challenges in the form of light, high oxygen concentration, low carbon dioxide concentration, increased pH, extreme variations in osmolarity, and changed bioavailability of zinc and calcium in the man-made laboratory product called seminal plasma. Possible future implications of these unphysiological conditions are discussed in relation to assisted reproduction and sperm research.

Partial characterization, sperm association and significance of N- and O-linked glycoproteins in epididymal fluid of rhesus monkeys (Macaca mulatta)

The present study investigated regional modifications of glycosylation status, sperm association and functional significance of N- and O-linked glycoproteins in epididymal luminal fluid of the rhesus monkey (Macaca mulatta). The predominant glycoproteins of the epididymal luminal fluid that increase in the extent of glycosylation or unmasking of exposed epitopes in a region-specific, maturation-dependent manner, included those of 150, 116, 68, 64, 58 (N- and O-linked) and 170 kDa (O-linked). The higher expression of 40 (N-linked), 38 (N- and O-linked) and 60, 56 and 33 kDa (O-linked) glycoproteins in the proximal caput epididymal fluid was followed by alteration or reorganization of 60, 38 and 33 kDa (O-linked) glycoproteins in the distal segments of the epididymis. The association of epididymal fluid glycoproteins with maturing spermatozoa was identified by generating polyclonal antiserum against monkey caudal sperm membrane in female albino rabbits. The antiserum crossreacted strongly with 58 and 33 kDa epididymal fluid glycoproteins of monkeys and also reacted with 116, 68, 58, 56 and 33 kDa glycoproteins from Triton X-100 extracts of human spermatozoa, indicating the presence of antigenically related components in both species. The functional significance of epididymal fluid glycoproteins in sperm functions was investigated by raising antiserum against a heavily glycosylated 58 kDa glycoprotein (MEF1) of caudal epididymal fluid, which crossreacted with the Triton X-100 extracts of epididymal spermatozoa of monkey and ejaculated human spermatozoa on immunoblots. In an in vitro micro-sperm agglutination assay, anti-MEF1 serum agglutinated both rat caudal epididymal spermatozoa and human spermatozoa. MEF1 seemed to be involved in fertilization as demonstrated by inhibition of fertility (100%) in female albino rabbits and rats immunized with this protein. A sperm-agglutinating 58 kDa glycoprotein of rhesus monkey epididymis with functional significance in fertility was identified, thus indicating that it is a potential candidate for contraceptive vaccine development.

Viability and protein phosphorylation patterns of boar spermatozoa agglutinated by treatment with a cell-permeable cyclic adenosine 3',5'-monophosphate analog

Boar spermatozoa become agglutinated with one another at the head when their intracellular cyclic adenosine 3',5'-monophosphate (cAMP)-signaling cascades are activated in the head. The aim of the present study is to examine viability and protein phosphorylation patterns of cAMP-dependently agglutinated boar spermatozoa. Ejaculated spermatozoa were washed and then incubated in a modified Krebs-Ringer HEPES medium containing polyvinyl alcohol (mKRH-PVA) plus 0.1 mM Sp-5,6-dichloro-1-beta-D-ribofuranosyl-benzimidazole-3',5'-monophosphorothioate (cBiMPS, a cell-permeable cAMP analog) at 38.5 degrees C up to 180 minutes. Aliquots of the sperm suspensions were recovered after various incubation periods and then used to examine the state of agglutination, the viability by SYBR14-PI staining and motility assay, and the state of protein phosphorylation by Western blotting and indirect immunofluorescence. In the control samples incubated without cBiMPS for 180 minutes, less than 30% of the total spermatozoa were agglutinated with one another at the heads, and more than 70% of the agglutinated spermatozoa were propidium iodide (PI)-positive (dead). However, the incubation with cBiMPS rapidly increased the percentages of head-to-head agglutinated spermatozoa to approximately 60% within 30 minutes, but did not significantly change them thereafter. In the samples incubated with cBiMPS for 180 minutes, moreover, the percentages of PI-positive cells of the agglutinated spermatozoa (approximately 30%) were significantly lower than those obtained in the control samples (more than 70%). This result was supported by the observation that the percentages of motile cells of the agglutinated spermatozoa were much higher in the samples incubated with cBiMPS for 180 minutes than in the control samples incubated without cBiMPS. As revealed by Western blotting and indirect immunofluorescence, cBiMPS-induced serine/threonine phosphorylation of the proteins (eg, >220 kd, 220 kd, 180 kd, 84 kd, and 54 kd) appeared mainly in the connecting and principal pieces of both agglutinated and free spermatozoa within 30 minutes, and additional phosphorylation occurred in the middle piece later than 30 minutes. Moreover, tyrosine phosphorylation of the proteins (eg, >220 kd, 190 kd, 93 kd, 59 kd, 54 kd, and 32 kd) was induced intensely in the connecting and principal pieces and moderately in the middle piece of almost one half of the agglutinated spermatozoa after incubation with cBiMPS for more than 30 minutes, but rarely in those of the free spermatozoa. These findings are consistent with the following suggestions: activation of the cAMP-signaling cascades leads to rapid (within 30 minutes) head-to-head agglutination in live spermatozoa; rapid (within 30 minutes) protein serine/threonine phosphorylation in the connecting and principal pieces of both cAMP-dependently agglutinated and free spermatozoa and subsequent (later than 30 minutes) phosphorylation in the middle piece of them; and slow (later than 30 minutes) protein tyrosine phosphorylation in the connecting, middle, and principal pieces of the cAMP-dependently agglutinated spermatozoa. Based on these suggestions, we conclude that many of cAMP-dependently agglutinated spermatozoa are live cells in which cAMP-signaling cascades leading to protein serine/threonine and tyrosine phosphorylation are activated in the whole flagellum.

A Digital Method of Sperm Immobilization Test: Comparison to the Conventional Method

Antisperm antibodies have been found in infertile patients and those causing immobilization of sperm are considered to be closely related to unexplained infertility. These antibodies are usually identified by a sperm immobilization test which involves counting motile sperm under microscope. This test is subjective as it relies on the judgement of the examiner with respect to sperm motility. In this study, we analyzed motile sperm by a digital method using Sperm Quality Analyzer. The results were compared with those obtained by the conventional method. We found that the two methods yielded identical results, with 14 of 66 samples tested being positive and 52 negative for sperm immobilizing antibodies. These results show that the digital method is objective and of value in the measurement of motile sperm in determination of sperm immobilizing antibodies.

[Therapeutic approaches to the treatment of infertility associated with antisperm antibodies production]

A lot of extensive investigations have been conducted to evaluate the potential role of antisperm antibodies (ASA) in infertile couples. But many questions still remain on the role of ASA in reproduction, testing methods, significant levels of ASA and treatment of immunologically-mediated human infertility, due to ASA. The aim of the present critical review was to the analyze the literature data, published in the last 20 years, concerning the most frequently used in the international centers methods for treatment of human immunological infertility associated with ASA production.

[Use of cryopreserved sperm in the microagglutination test]

OBJECTIVE

The aim of this study was to find out the behavior of sperm cryopreserved in microagglutination test (TAT).

METHODS

TAT using native sperm pertains to the screening methods in spermagglutinating antibodies. Spermatozoa cryopreserved in egg-yolk medium, just in seminal plasma or in the commercial made medium--Medi-Cult (Denmark) were used in this study.

SETTING

Department of Gynaecology and Obstetrics, Institute of Clinical Immunology and Allergology Medical Faculty of Charles University, Pilsen.

RESULTS

367 tests were performed together. It includes 108 examinations with native spermatozoa, 59 with spermcryopreserved in egg-yolk medium, 109 with spermcryopreserved just in seminal plasma and 91 in Medi-Cult medium. The correspondance of results with native and cryopreserved sperm was found in 24% for egg-yolk medium, in 69% for seminal plasma and in 77% for commercial medium Medi-Cult.

CONCLUSION

The results show that spermcryopreservation in Medi-Cult medium or just in the seminal plasma are able to be used in TAT for detection of spermagglutinating antibodies.

Immunolocalization of anti-agglutinin for spermatozoa in boars

A boar "anti-agglutinin," which inhibits head-to-head agglutination of spermatozoa, has been identified as a 25-kDa sialoprotein contained in epididymal and seminal plasma. This study was conducted to determine the location of the anti-agglutinin on spermatozoa and in various organs, including epididymides, by indirect immunofluorescence and Western blotting techniques. Ejaculated boar spermatozoa were washed and subjected to immunocytochemical observation. Epididymal plasma was recovered from three different regions of epididymides and subjected to sodium dodecylsulfate (SDS)-polyacrylamide gel electrophoresis (PAGE) and Western blotting. Twelve kinds of organs (testis, epididymis, seminal vesicle, prostate, heart, liver, kidney, spleen, stomach, small intestine, lung, and muscle) were recovered from boars. The unilateral epididymides were fixed, cut into 10-microm frozen sections, and subjected to immunohistochemical observation. The other organs were homogenized and used for SDS-PAGE and Western blotting. Immunocytochemical observations revealed that the antiserum strongly recognized the acrosomal region and equatorial segment on unfixed and methanol-fixed spermatozoa. Immunohistochemical observations revealed that the epithelia of the epididymal ducts were recognized by the antiserum mainly in the corpus epididymides. Moreover, the antiserum reacted with the luminal contents of the corpus and cauda epididymides. However, no specific reaction was detected in the caput epididymides. Western blotting showed that the antiserum selectively recognized a band of the anti-agglutinin in the corpus and cauda epididymal plasma, although no band was detected in the caput epididymal plasma. In the extracts from various organs, the single band was detected in the corpus and cauda epididymides at the same mobility as the anti-agglutinin, but not in the other organs. Based on these results, the following matters concerning the anti-agglutinin are discussed: (1) the importance of its association with the acrosome of spermatozoa in inhibiting sperm head-to-head agglutination; (2) its origin in the epididymis; and (3) its tissue specificity.

Sperm-lectin agglutination combined with swim-up leads to an efficient selection of highly motile, viable and heterogeneous ram spermatozoa

Lectins, high molecular weight glycoproteins with different sugar-binding specificity, are able to agglutinate different cell types. The recovery of high-quality spermatozoa can be facilitated by the agglutination induced by the lectin binding. The objective of this study was to combine sperm-lectin agglutination with a dextran/swim-up procedure for developing a new selection technique for ram spermatozoa. To study sperm quality, cell viability (plasma membrane integrity), the HOS-test response and progressive individual motility were assessed. Simultaneously, centrifugal countercurrent distribution (CCCD) in an aqueous two-phase system was carried out to analyze sperm surface heterogeneity. Semen from 3 mature Saltz rams was pooled, and 0.5-mL aliquots were incubated with 4 fluorescein-labelled lectins (ECL, JAC, PSA, RCA). Then, a dextran solution was gently added and overlaid with medium. The top layer of the medium containing the spermatozoa was collected and replaced by careful addition of fresh medium. The incubation sequence was repeated 3 times at 10-min intervals. The consecutive 4 top layers obtained were pooled to give the swim-up combined sample. The highest rate of improvement in sperm quality was obtained after incubation with RCA, with a 50% increase in progressive individual motility, 21.6% in HOS value and 39.5% in viability. Total cell recovery was 64% (1.56x10(9) cells), with a viable cell recovery rate of 86%. The obtained sample showed 82% motility, 80% HOS score and 77% viability, up from the pre-swim-up values of 51, 60 and 57 %, respectively. Comparative CCCD analysis revealed a very high heterogeneous population in the RCA/swim-up sample obtained, while a much more homogeneous population was obtained in the sample after the dextran/swim-up procedure previously developed byus With this simple method, a large proportion of highly-motile spermatozoa with preserved plasma membrane and high heterogeneity can be obtained. These results strongly suggest that this selection procedure could result in a high fertility rate.

Direct evidence for the secretion of lactoferrin and its binding to sperm in the porcine epididymis

Lactoferrin has been for the first time purified from the porcine cauda epididymal fluid as a 70 kDa protein. Both Western and Northern blot analyses show that lactoferrin is synthesized in the regions from the distal caput to the cauda epididymis and secreted into the luminal fluid. Lactoferrin is first secreted as a 75 kDa glycoprotein and its carbohydrate moieties are gradually digested to form 70 kDa protein in the cauda epididymis. Lactoferrin has already bound to the surface of the epididymal sperm because the anti-lactoferrin antiserum induces the mature sperm tail-to-tail agglutination. These results strongly suggest new physiological functions of lactoferrin on the sperm maturation in the epididymis.

Contraceptive effect of sperm-agglutinating monoclonal antibodies in rabbits

Immune infertility in humans correlates clinically with the presence of anti-sperm antibodies that trap (agglutinate) sperm in semen and cervical mucus. To test whether sperm-agglutinating antibodies can be effective contraceptive agents, several mouse anti-rabbit sperm (MARS) sperm-agglutinating monoclonal antibodies (mAbs) were developed that rapidly and completely agglutinate sperm: MARS-M3 (IgM), MARS-G16 (IgG3), and MARS-G17 (IgG3). Contraceptive efficacy of these mAbs was tested by mixing the mAb with 0.1 ml semen (approximately 1/5 of a whole ejaculate) immediately before artificially inseminating rabbits paracervically. This paracervical dose of semen provided a rigorous test since it delivered several thousand times more fertilizing doses than does a human ejaculate. All of the mAbs were contraceptively effective, and MARS-G16 reduced the number of fetuses per animal by 88% and 95% with doses of 150 microg and 2 mg, respectively. The contraceptive efficacy of the MARS mAbs in the rabbit suggests that human sperm-agglutinating mAbs may be effective agents for vaginal contraception in humans.

Presence of immunoglobulin binding factor on human sperm surface as sperm coating antigen

The presence of IgBF as a sperm-coating antigen was demonstrated by showing that anti-IgBF antibodies agglutinate and immobilize human sperm and by localizing IgBF on sperm surface by immunofluorescence staining. Several components interacting with sperm immobilizing antibodies, known to be involved in infertility, are sperm-coating antigens. Anti-IgBF antibody in vitro did not block the ability of human sperm to penetrate human zona pellucida and zona-free hamster egg. Anti-IgBF activity of sera obtained from infertile women did not correlate with the titers of anti-sperm antibodies measured by the sperm immobilization test. IgBF is a sperm-coating antigen and may play a role in suppressing antibody production against alloantigenic sperm in the female reproductive tract.

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.

Sperm auto - antibodies and anti-nuclear antigen antibodies in chronic dioxin - exposed veterans

The authors studied anti-nuclear antibodies (ANA) in 25 chronic dioxin - exposed veterans by IIF technics with Hep-2 cell line and sperm autoantibodies by agglutination test of Franklin-Dukes. The site of antibody binding on spermatozoon is detected by IIF test. The control group for ANA detection is 63 healthy persons of the same age as that of dioxin - exposed veterans and the control group for sperm autoantibodies is 36 healthy males of 28-63 years old, having 1-2 children. Obtained results show that the rate of ANA positive in veterans group is normal, and sperm auto-antibodies is also at normal range. The site of antibody binding on spermatozoon is predominantly head - head, rarely head - neck or tail - tail.

Functional characterization of the primate sperm acrosomal antigen (PSA-63)

Monoclonal antibody (HS-63) raised in mice against human ejaculated sperm, polyclonal antibodies raised in rabbits against the cognate mouse testicular antigen (MSA-63; or Fab) and polyclonal antibodies raised in the rabbit against recombinant fusion proteins (GST-63) showed acrosomal localization in permeabilized rhesus monkey and human ejaculated sperm. Tail localization of the cognate primate sperm antigen (PSA-63) was also seen with intact MSA-63 antibodies and Fab fragments. The ability of these antibodies to inhibit sperm binding to the zona pellucida was measured with hemizona binding assays (HZAs). HS-63 (1.2 mg/ml) inhibited rhesus monkey sperm binding (mean +/- SEM) to homologous hemizonae (treatment, 15.5 +/- 3.3; control, 58.9 +/- 9.4; P < 0.025), whereas comparable concentrations of protein from nonimmunized mouse preparations were inactive (ascites fluid, 67.6 +/- 43.5; no ascites fluid, 72.0 +/- 44.6). Intact MSA-63 antibodies inhibited (up to 99%) monkey sperm-zona binding in a concentration-dependent manner. Moreover, inhibition in this case by intact MSA-63 antibody was limited to capacitated sperm. Similarly, intact MSA-63 antibodies inhibited (up to 85%) human sperm binding to homologous zonae in an antibody concentration-dependent manner. Fab fragments derived from MSA-63, when present in insemination mixtures (0.5 mg/ml), inhibited (P < 0.01) primate sperm binding to homologous hemizonae (monkey, 9.6 +/- 3; human sperm 9.4 +/- 2) compared with matched hemizona controls (monkey, 117 +/- 29; human, 20.4 +/- 3). Furthermore, rhesus monkey sperm-zona binding was reduced by 84% in the presence of rabbit anti-GST-63 antibodies.(ABSTRACT TRUNCATED AT 250 WORDS)

Potential contraceptive use of epididymal proteins: evidence for the participation of specific antibodies against rat epididymal protein DE in male and female fertility inhibition

Previous studies in our laboratory indicated that immunization of male and female Wistar and Lewis rats with epididymal protein DE, resulted in the development of anti-DE antibodies in over 90% of the animals, with a significant and reversible reduction of fertility. In the present study, ELISA assays performed to analyze the evolution of the immune response indicated that antibody levels in the sera of immunized animals reached a maximum at 8 weeks after the initial injection and then gradually decreased, returning to control values by the end of the sixth month. Western blot experiments demonstrated that the immune sera specifically recognized DE in epididymal sperm extracts and epididymal cytosol, while no reaction was observed with different reproductive and essential organs. The immune sera were also capable of recognizing DE on the surface of both fresh and capacitated sperm as indicated by indirect immunofluorescence experiments. Finally, the exposure of sperm to immune sera prior to uterine insemination resulted in a significant (P < 0.05) reduction in the percentage of fertilized eggs compared to controls, with no effect on sperm motility and viability, nor on their ability to undergo capacitation. Together, these results support the participation of the raised antibodies as mediators of the antifertility effect and suggest a specific interference at the sperm-egg interaction level.

Relationship between the direct mixed antiglobulin reaction (MAR) test and spontaneous sperm agglutination in men from infertile couples

To determine the relationship between the direct MAR test and spontaneous sperm agglutination in men from infertile couples, semen samples from 160 men were studied. Spontaneous sperm agglutination was present in 80 samples, and absent in the others. Routine semen analysis and the direct MAR test were performed on all samples. The incidence of positive MAR tests in samples with and without spontaneous sperm agglutination were 15 and 0 per cent respectively (p < 0.05). There were no significant differences in mean sperm concentration, motility, and morphology between the samples with and without spontaneous sperm agglutination, and between the positive and negative MAR test groups. It can be concluded that spontaneous sperm agglutination relates significantly to antisperm antibodies detected by the direct MAR test, and this factor could be used as indication for antisperm antibody testing of infertile men.

Carbohydrate moieties on sperm surface: physiological relevance

OBJECTIVES

To study the cross-reactions between mouse monoclonal antisperm antibodies and somatic cells or bacteria, to identify the antigenic determinants responsible for such cross-reactions, and to correlate between the antibody function and determinant recognition.

DESIGN

Activities of monoclonal antibodies (mAbs) were characterized by immunosorbent assay of RIA technique; sperm epitopic characterization was performed in lectin-blocking and sugar competitive assays and correlated with functional assays.

SETTING

Procedures were performed in a university laboratory.

RESULTS

The extensive cross-reactivity between antigenic determinants of sperm, erythrocytes, and bacteria (but not bacterial deglycosylated lipopolysaccharides) was observed. The analytic procedures indicated predominant mAb reactions to carbohydrates such as fucose, galactose, mannose, N-acetylglucosamine and N-acetylgalactosamine. Approximately half of the 30 tested mAbs interfered in the functional assays, that is, sperm agglutination, immobilization, and zona-free penetration.

CONCLUSIONS

Sperm carbohydrates seem to induce antibody reactions to common antigenic determinant(s) present on gametes, somatic cells, and infectious agents. Thus molecular mimicry between bacteria and sperm can be a major factor inducing antisperm immunological reactions. Obtained antisperm mAbs, reacting to glycosylated epitopes, presented very strong properties in sperm agglutination and/or immobilization. This did not correlate with inhibiting properties of some antibodies in xenogeneic zona-free penetration test, that is, this assay possibly is not based on oligosaccharide mediation.

Spermagglutination by bacteria: receptor-specific interactions

The influence of genital infection on infertility has yet to be elucidated. We examined receptor-ligand interactions between sperm and Escherichia coli from patients with prostatitis. Two E. coli surface adhesins (P-fimbriae, type 1 fimbriae) and their specific receptor saccharides (alpha-galp-1-4-beta-galp-O-methyl [gal-gal], mannose) were evaluated. Bacterial concentrations of 10(4) caused spermagglutination. P-fimbriae caused tail-tail spermagglutination that was inhibited by gal-gal. D-mannose concentrations are highest in the acrosomal region and type 1 fimbriae caused head-head agglutination that was inhibited by mannose. Strains with both fimbriae caused head-head and tail-tail agglutination that was inhibited by a mannose/gal-gal combination. E. coli agglutinated 40-75% of motile sperm. Seminal fluid provided 50-100% protection, with lower effectiveness against type 1 fimbriae. Understanding bacteria-spermatozoa interactions at the receptor-ligand level holds potential for treatment of infertility and development of spermagglutinating contraceptives.

Incidence of antisperm antibodies in patients with carcinoma of the testis and in subfertile men with normogonadotropic oligoasthenoteratozoospermia

The incidence and the clinical relevance of sperm-reactive antibodies in subfertile men and in testicular cancer patients were assessed in a pilot study. The sera of 42 men with normogonadotropic oligoasthenoteratozoospermia (OAT syndrome, n = 20) or carcinoma of the testis after inguinal semicastration (n = 22) were analyzed for agglutinating antisperm antibodies using fluorescein-labeled antiglobulin. In the group with the OAT syndrome, the incidence of sperm-reactive antibodies was only 5%, which is comparable to that in normal fertile men. Although the incidence of 18% in the testicular cancer patients was markedly higher, only 2 of the patients in question had abnormal spermiograms, which in one case could, moreover, be explained by previous radiation therapy. In summary in this small group of patients, serum monitoring for sperm-reactive antibodies appeared to be of limited clinical relevance in patients with the OAT syndrome and in testicular cancer patients.

Vasovasostomy results in 66 patients related to obstructive intervals and serum agglutinin titres

In this series we present the results of a retrospective analysis of 66 vasovasostomy procedures performed between 1983 and 1991. Obstructive intervals and serum antisperm antibodies were correlated with pregnancy and patency rates. With obstructive intervals of less than 5 years a patency rate of 100% (31/31) was obtained. Even more than 10 years after reversal, pregnancy occurred in 25% (2/8) of the patients. Preoperative serum antisperm antibodies were correlated with pregnancy rates. Patients with a high agglutinin titre of 1/64 obtained a pregnancy rate of 23% (3/13). Those men who had no circulating antisperm antibodies in their blood had a significantly better chance in obtaining pregnancy (pregnancy rate 80%). In this study we accounted for an overall pregnancy rate of 51.5% (34/66) versus an overall patency rate of 84.8% (56/66). Neither long obstructive intervals nor high antisperm antibody titres should dissuade a surgeon from performing a vasovasostomy procedure.

Human aspirated epididymal spermatozoa: ultrastructural, immunological, kinetic study and fertilization ability. MESA Italian Group

The analysis of ultrastructural, kinetic and immunological characters of spermatozoa aspirated from the proximal segments of the epididymis of patients with congenital absence of vas deferens showed that most of them are defective. These spermatozoa, utilized in different procedures of assisted reproduction, showed a reduced fertilization rate. The data obtained in this study seem to indicate that CAV affects the development and functional properties of epididymal spermatozoa.

Laboratory testing in the evaluation of male infertility. A rational approach

Laboratory testing is an integral component of the evaluation of the infertile man. This testing must be appropriate and specific for the individual couple. As there are many tests that evaluate various aspects of infertility, the urologist must understand what information the tests can offer as well as the limitations of each assay. The semen analysis remains the cornerstone of the evaluation but is not a functional assay. Other assays such as sperm-cervical mucus tests, hemizona assays, and the sperm-penetration assay are functional tests. Through the appropriate use of these and other tests, the urologist will be capable of better and more accurately counseling the infertile couple.

Use of particle filters for increased practicability in sperm processing: application to the indirect immunobead test

The use of sterile particle filters is described for the washing and incubation of living sperm before the indirect IBT. The filters greatly simplify the technique, shorten its duration, and remove all centrifugation steps that have potentially detrimental effects on the sperm. The same filters have a variety of applications and can be used whenever sperm have to be washed or incubated before biochemical tests including acrosome binding studies and flow cytometry.

Treatment of immunological infertility by sperm washing and intrauterine insemination

The purpose of this study is to review our experience with sperm washing and intrauterine insemination as a method to reduce the presence of sperm antibodies in serum of couples with immunological infertility. Our results support the premise that sperm washing and intrauterine insemination can diminish the level of sperm-bound immunoglobulins and can improve the chance of conception in a selected group of couples with a diagnosis of immunological infertility. Patients with > 50% attachment of IgG, IgA, or both antisperm antibodies in this study had a greater chance of achieving a pregnancy. The high level of antibody attachment seen in our study appears to represent true immunological infertility and therefore is more likely to respond to therapy that reduces antibody attachment and bypasses cervical mucus.

Binding of a 15 kDa glycoprotein from spermatozoa of boars to surface of zona pellucida and cumulus oophorus cells

A highly purified 15 kDa glycoprotein isolated from ejaculated spermatozoa was used to raise antisera in female rabbits. An indirect immunofluorescence technique was used to detect the antigen in the seminal vesicle tissue and on the acrosomes of ejaculated, native and capacitated, boar spermatozoa. No immunoreactivity was detected on cells of the seminiferous tubules (spermatogonia, spermatocytes, and spermatids), on spermatozoa in the ductus epididymis and in cells of the epididymal and testicular tissues. These observations support the view that the 15 kDa protein is produced in the seminal vesicle secretory epithelium, and is attached to the sperm plasma membrane during the exposure of spermatozoa to seminal vesicle compounds. The observations that the antigen remained on the acrosome of ejaculated spermatozoa after capacitation and blocked sperm-oocyte binding in vitro suggest that the antigen plays a role in sperm-egg interactions. The strong immunoreactivity exhibited by cumulus cells after incubation of antisera with the porcine egg surrounded by cumulus cells shows the possible importance of the 15 kDa glycoprotein for contact of spermatozoa with cells of the cumulus oophorus surrounding the egg.

[Immunoreactivity of Mycoplasma hominis PG21 antigens and human sperm antigens]

The authors selected from the WHO bank for reproductive immunology ten sera containing concurrently antispermatozoal antibodies and antibodies against Mycoplasma hominis PG21. By absorption examination of selective sera with a different concentration (10(9)/ml, 3.10(8)/ml, 10(8)/ml) of human spermatozoa and a rinsed sonicate of Mycoplasma hominis PG21 in dilutions of 1:20, 1:80, 1:320 the authors did not find a crossed immunoreactivity between sperm antigens and mycoplasmic antigens.

Cyclic corticosteroid immunosuppression is unsuccessful in the treatment of sperm antibody-related male infertility: a controlled study

In this double blind cross-over study, 20 infertile men, who had sperm antibodies detected by the mixed antiglobulin reaction (MAR test) in the ejaculate and by the tray agglutination test (TAT) in serum, were treated with 40 mg/day prednisolone or placebo from days 1 to 10 of the partners' menstrual cycle. Patients were randomly allocated to different treatment groups. While group 1 started with placebo followed by verum for three consecutive cycles, group 2 began with verum and continued with placebo. All patients had regular intercourse (n = 19) or intra-cervical insemination at ovulation (n = 1). A post-coital test or a sperm penetration test was performed during verum and placebo regimes. Blood samples were drawn from the male partner at this time to control the efficacy of prednisolone treatment by checking the TAT titre. No pregnancy occurred during prednisolone or placebo treatment. In eight of 12 patients, post-coital testing showed little improvement and antibody titres decreased in seven of 16 patients. Side-effects from medication were reported by eight patients (seven verum and one placebo cycle) and caused treatment to be discontinued in two cases. Five patients' partners conceived at a later stage by intrauterine insemination with spermatozoa prepared by 'swim up' (n = 3) or by in-vitro fertilization (IVF n = 2). Thus high dose corticosteroid therapy was ineffective in achieving pregnancies induced by infertile men positive for antisperm antibodies. Since side-effects of corticosteroids should not be underestimated in otherwise healthy men, other reproductive techniques such as intrauterine insemination or IVF should be offered to such couples.

Complement component C1q and its receptor are involved in the interaction of human sperm with zona-free hamster eggs

C1q is a component of the classical complement pathway that can react with the Fc-fragment of immunoglobulins and with other proteins, such as fibronectin, laminin, and a specific C1q receptor present on several cell types. Given its role in many adhesion systems, mainly related to phagocytosis, we tested the effects of C1q on the interaction between human spermatozoa and zona-free hamster eggs. The presence of C1q in the medium used for gamete coincubation resulted in promotion of sperm-oolemma adhesion and an inhibition of penetration. The number of adherent sperm per egg at 5 micrograms/ml concentration was 90 +/- 35 vs. 29 +/- 7 for the control (P less than 0.001). At 1 microgram/ml, the lower concentration at which C1q had an effect, the number of penetrating sperm/egg was 0.6 vs. 1.7 for the control without C1q (P less than 0.01), and the percent of penetrated eggs was 28% vs. 85%. At 50 micrograms/ml, the percent of penetrated eggs was 7%, with a penetration index of 0.07. The addition of C1q to the medium resulted in sperm agglutination, which varied between sperm donors. The presence of C1q receptors, as detected by anti-C1qR monoclonal antibodies (Mabs), was demonstrated both on zona-free hamster eggs by immunobead rosetting and on human spermatozoa by immunobead binding and indirect immunofluorescence. Mabs directed against different epitopes of C1qR had different effects on gamete interaction, with a partial inhibition of penetration mediated by some of them. The binding of C1q to antibody-free human spermatozoa was also demonstrated both by means of indirect immunofluorescence and utilizing 125I-C1q.(ABSTRACT TRUNCATED AT 250 WORDS)

Statistical analysis in andrology

The authors began a statistical study on a file group of 9384 records of semen analyses and anamnestic data (P-1). From this file, they selected a group of 5191 patients having undergone analysis at least one time (P-2) and a file of 850 patients having undergone analysis at least three times (P-3). Finally a new group, derived from P-3, of 203 patients followed by their medical team was created (P-4). Two control groups-composed of 20 sperm-bank donors (DON) and 740 prevasectomy subjects (VAS)-were also created. Frequency distributions and cluster analyses were carried out. The multivariate statistical analysis allows a distinction to be made between fertile and infertile subjects regarding a patient's clinical condition. The most discriminating parameters appear to be sperm concentration and, above all, forward motility and sperm morphology.

[Effect of antisperm antibodies in males on in vitro fertilization]

To investigate the effect of antisperm autoantibodies on the process of in vitro fertilization, sperm immobilization test and sperm agglutination test with serum, and direct immunobead test with semen were conducted on the male partners of 101 infertile couples. Fourteen patients were positive in at least one of these three antisperm antibody tests. Six of them were associated with a low fertilization rate (= LFR group, less than 50% of mature oocytes were fertilized), while the other 8 patients had a normal fertilization rate (= NFR group). The spermatozoa in the LFR group were bound to immunobeads of both IgG and IgA classes. In contrast, the spermatozoa in the NFR group were not bound to IgA. The results of the tests with serum were not related to the outcome of fertilization. By rapid dilution and washing of the semen containing antisperm autoantibodies, the percentage of spermatozoa bound to IgG decreased significantly. However, the rate of fertilization was not improved. Six pregnancies were achieved after 13 embryo transfers in the 14 patients. We conclude that the fertilization rate is reduced when spermatozoa are bound to both IgG and IgA antisperm autoantibodies, or to IgA alone. Antisperm autoantibodies do not seem to hamper embryonal development and implantation.

Partial purification of a boar sperm membrane protein inducing sperm agglutinating antibody

For the development of immunological contraception, attention is being concentrated on the possibility of using a sperm membrane antigen. Boar sperm membrane was extracted with triton-X 100 and fractionated by Sephadex G-150 column chromatography. The glycosylated and nonglycosylated portions of protein peaks from the gel filtration were obtained by fractionating on concanavalin A-Sepharose and eluting the bound protein with 0.3 M methyl mannoside. A glycosylated fraction was found to induce sperm agglutinating antibodies in rabbit. The partially purified protein has a molecular weight of 30 kilodaltons, as determined by sodium dodecyl polyacrylamide gel electrophoresis. Further work is planned on the histochemical determination of the origin of this protein and species cross-activity of the antibody.