A flow cytometric study on the effect of low dose cyclic prednisolone treatment on sperm-bound antibody levels

Antisperm Antibody Testing: A Comprehensive Review of Its Role in the Management of Immunological Male Infertility and Results of a Global Survey of Clinical Practices

Antisperm antibodies (ASA), as a cause of male infertility, have been detected in infertile males as early as 1954. Multiple causes of ASA production have been identified, and they are due to an abnormal exposure of mature germ cells to the immune system. ASA testing (with mixed anti-globulin reaction, and immunobead binding test) was described in the WHO manual 5th edition and is most recently listed among the extended semen tests in the WHO manual 6th edition. The relationship between ASA and infertility is somewhat complex. The presence of sperm agglutination, while insufficient to diagnose immunological infertility, may indicate the presence of ASA. However, ASA can also be present in the absence of any sperm agglutination. The andrological management of ASA depends on the etiology and individual practices of clinicians. In this article, we provide a comprehensive review of the causes of ASA production, its role in immunological male infertility, clinical indications of ASA testing, and the available therapeutic options. We also provide the details of laboratory procedures for assessment of ASA together with important measures for quality control. Additionally, laboratory and clinical scenarios are presented to guide the reader in the management of ASA and immunological male infertility. Furthermore, we report the results of a recent worldwide survey, conducted to gather information about clinical practices in the management of immunological male infertility.

Unexplained male infertility: diagnosis and management

Unexplained male infertility is a diagnosis reserved for men in whom routine semen analyses results are within normal values and physical as well as endocrine abnormalities were ruled out. In addition to erectile problems and coital factors, immunologic causes and sperm dysfunction may contribute to such condition. New etiologies of unexplained male infertility include low level leukocytospermia and mitochondrial DNA polymerase gene polymorphism. Contemporary andrology may reveal cellular and sub-cellular sperm dysfunctions which may explain subfertility in such cases, thus aiding the clinician to direct the further work-up, diagnosis and counseling of the infertile male. The objective of this article is to highlight the concept of unexplained male infertility and focuses on the diagnosis and treatment of this condition in the era of modern andrology and assisted reproductive techniques. Extensive literature review was performed using the search engines: Pubmed, Science-direct, Ovid and Scopus.

Antisperm immunity and infertility

Immunoinfertility is one of several causes of infertility in humans. Although progress on antisperm immunity and infertility has advanced during the past three decades, the nature of a real antisperm antibody (ASA) is still poorly understood. Dozens of sperm antigens have been isolated and characterized in association with infertility. However, it is difficult to identify a single predominant target antigen that could interact with all the ASAs. There are some protective mechanisms preventing ASA production in males and females. As chronic infection, vasectomy and vasovasostomy, heavy metals, and testicular cancer and torsion may induce the production of ASAs, they may be responsible for decreased motility and sperm penetration of cervical mucus, and the blockage of the acrosome reaction and the sperm-egg interaction. Many ASA assay methods have been developed, each with advantages and disadvantages. Efforts for the treatment of ASA-mediated infertility have been attempted. However, current therapy for ASA-associated infertility is almost empiric and largely unproven.

Antisperm antibodies detection by flow cytometry is affected by aggregation of antigen-antibody complexes on the surface of spermatozoa

Flow cytometry (FCM) analysis of live antibody-coated spermatozoa subjected to immunofluorescence staining (FCM test) is considered an objective method for the quantitative detection of antisperm antibodies (ASA). But the cross-linking of cell surface antigen (Ag) with bivalent antibodies and/or antigen-antibody (Ag-Ab) complexes with second antibodies may induce the reorganization of surface components (patching and capping) and result in their shedding from the sperm surface. The present study estimates the relationship between aggregation of Ag-Ab complexes on the sperm surface and the results of indirect FCM test. Swim-up spermatozoa of normozoospermic men were incubated with ASA-positive sera from infertile patients and with second antibodies fluorescein isothiocyanate (FITC)-labelled goat anti-human IgG polyclonal antiserum under different conditions and then analysed by FCM and fluorescence microscopy. It was shown that low temperature, cytochalasin B, excess or lack of the primary and/or secondary antibodies and sperm fixation by paraformaldehyde may inhibit aggregation and shedding of Ag-Ab complexes and dramatically increase ASA quantity determined on the sperm surface. However, inhibition of aggregation on the live sperm surface was observed only in a minority of ASA-positive samples and was poorly reproducible using semen of different donors. A high probability of Ag-Ab complex shedding from the sperm surface during experimental manipulation limits the use of indirect FCM test for quantitative ASA determination.

Antisperm antibodies: etiology, pathogenesis, diagnosis, and treatment

OBJECTIVE

To critically review the English-language literature and describe the current diagnosis, prevalence, etiology, and treatment of antisperm antibodies (ASA).

DESIGN

A comprehensive literature search of the English-language literature published between 1966 and December 1997 was performed on MEDLINE. Articles were also located via bibliographies of published works.

RESULT(S)

Data were excerpted from articles identified by MEDLINE search. The diagnosis, prevalence, etiology, and treatment of ASA are described.

CONCLUSION(S)

There is sufficient evidence that ASA impair fertility in couples with unexplained infertility. A number of different methodologies are available, which may be used in their detection. However, in many cases, test interpretation is subjective. Although there is not enough evidence to support systemic treatment for ASA, application of a variety of assisted reproductive technologies improves outcome.

Flow cytometry study on the effect of serum and peritoneal fluid of women on sperm-binding activity of immunoglobulin G antisperm antibodies

OBJECTIVE

To investigate the influence of sera and peritoneal fluids (PFs) from fertile and infertile women on the binding of antisperm antibodies to the surface of spermatozoa.

DESIGN

The immunoglobulin (Ig) G antisperm antibodies binding to the surface of liver spermatozoa was evaluated after their incubation in antisperm antibodies-positive serum from an infertile male in the presence and absence of female sera or PFs.

SETTING

Russian Scientific Center for Obstetrics, Gynaecology, and Perinatology.

PATIENT(S)

Serum and PF samples from fertile and infertile women; antisperm antibodies-positive serum from infertile men; high-quality fresh semen from healthy donors.

INTERVENTION(S)

Serum samples were obtained from fertile and infertile women and from infertile men. Peritoneal fluids were collected during routine laparoscopy.

MAIN OUTCOME MEASURE(S)

The proportion of spermatozoa positive for IgG antibodies and the quantity of antisperm antibodies on the sperm surface measured by flow cytometry (FCM).

RESULT(S)

The addition of sera from fertile or infertile women with endometriosis or pelvic adhesion disease to an IgG antisperm antibodies-positive male serum resulted in significant inhibition of the antisperm antibodies binding to the sperm surface.

CONCLUSION(S)

Sera of fertile as well as infertile woman contain factors that block IgG antisperm antibodies binding to the surface of live spermatozoa.

A placebo-controlled flow cytometric study of the effect of low-dose prednisolone treatment on sperm-bound antibody levels

In this placebo-controlled study the effect of short term, low-dose prednisolone treatment on sperm-bound antibody levels was investigated using an objective flow cytometric (FCM) measurement. Twenty infertile men, positive for antisperm antibodies by the mixed antiglobulin reaction (MAR) test, were treated with either 20 mg/day prednisolone (n = 10) or placebo (n = 10) for 3 weeks. The two groups were similar with respect to sperm count, motility and antibody levels. The proportion of spermatozoa positive for IgG and IgA antibodies and the antibody load, expressed as the number of IgG and IgA antibody molecules bound per spermatozoa were measured by FCM. The study showed that, overall, the antibody levels measured before and after treatment with low-dose prednisolone or with placebo were not statistically different. However, in the prednisolone group a marked decrease in the proportion of spermatozoa positive for IgG and IgA antibodies was observed in two of the patients. An examination of the FCM data of these two patients revealed that, in their ejaculates, only the spermatozoa with low to moderate amounts of sperm-bound antibodies had responded to prednisolone treatment, while spermatozoa with high levels of sperm antibodies had remained resistant to prednisolone. These results point to the existence of an as-yet-undefined subset of prednisolone-responsive, antibody--positive spermatozoa.

Seminal fluid antisperm antibodies measured by direct flow cytometry do not correlate with those measured by indirect flow cytometry, the indirect immunobead test, and the indirect mixed antiglobulin reaction

OBJECTIVE

To compare the direct flow cytometric (FCM) measurement of sperm-bound antibodies with the indirect FCM measurement of unbound antisperm antibodies in seminal plasma of the same ejaculates. To compare the FCM measurements with the indirect mixed antiglobulin reaction (MAR) and the indirect immunobead test (IBT) performed on the same seminal plasmas.

SETTING

University hospital-based infertility service.

PATIENTS

Eleven infertile men with a positive immunoglobulin (Ig) G direct MAR test and antibody positivity on the direct FCM measurements. Four control patients with a negative IgG-direct MAR test.

MAIN OUTCOME MEASURES

The proportion of spermatozoa positive for IgG and IgA antibodies as measured by various tests.

RESULTS

The direct and indirect FCM measurements for sperm-bound antibodies from seminal plasma did not correlate with each other. In general, IgG antibodies were not detectable by indirect FCM whereas IgA were detected in lower proportions than by direct FCM measurements. Weak correlation was observed between the indirect FCM, indirect MAR, and indirect IBT measurements.

CONCLUSION

Nearly all of the IgG and some of the IgA antisperm antibodies in seminal fluid bind to spermatozoa. Thus, indirect tests to measure antisperm antibodies from seminal plasma are likely to miss the presence of antisperm IgG antibodies while detecting some cases of IgA antibodies.