Comparison of flow cytometric measurement of seminal antisperm antibodies with the mixed antiglobulin reaction and the serum tray agglutination test

A comparison of the sperm mixed-agglutination reaction test with the peroxidase-labelled protein A test for detecting antisperm antibodies in infertile men with varicocele

OBJECTIVE

To compare the sperm mixed-agglutination reaction (sMAR) with the peroxidase-labelled protein A method (POPA) in infertile patients with varicocele.

PATIENTS, SUBJECTS AND METHODS

The study comprised 30 men with a history of varicocele-associated infertility and 30 fertile men (control group). Antisperm antibodies against spermatozoa in the semen and against progenitor spermatozoa in testicular tissue were detected using the two methods.

RESULTS

The tests were positive in 15 (50%) of patients with both the sMAR and the POPA methods, while no autoantibodies were detected in the control group. There were no significant differences between the methods. The sensitivity and specificity of both tests was approximately 93%, with no significant difference between them (P>0. 05).

CONCLUSION

Both methods may be used for detecting sperm autoantibodies in infertile patients with varicocele.

Flow cytometric determination of binding of monoclonal antibodies to human spermatozoa

Although several monoclonal antibodies to sperm antigens are available, only few systematical reports on the appearance of distinct antibody binding structures in spermatozoa of infertile patients are available. We studied the binding frequency of six monoclonal antibodies (TUS-1, -2, -10, -17, -19, -20) by means of a flow cytometer in different semen samples and their possible relationship to other sperm parameters, in particular to the motility parameters as determined by computer-assisted semen analysis. The percentage of vital spermatozoa binding the different antibodies was 21.5% (TUS-2) to 52.1% (TUS-20). The percentage binding was higher in samples with normozoospermia than in those with oligo-asthenoteratozoospermia. A significant correlation occurred between sperm concentration and the percentage of spermatozoa stained by TUS-2 and TUS-17; between motile spermatozoa and those binding TUS-17 and TUS-20; the velocity average path and those binding TUS-17; an inverse correlation occurred between the morphologically-abnormal spermatozoa and those binding TUS-20; an inverse correlation between TUS-17 and acrosin. We conclude from our results that although the antigens of the antibodies concerned are not yet characterized, the determination of antibody binding will give additional information on the functional status during capacitation and acrosome reaction of spermatozoa.

Review: in vitro spermicidal tests

This review analyzes in vitro spermicidal tests that have been used to evaluate the spermicidal activity of contraceptive products. Special requirements and processes in numerous technologies were also reviewed. Nonoxynol-9 (N-9) was used as an example of a vaginally delivered spermicidal agent, and its spermicidal potency was compared by various spermicidal tests, such as Sander-Cramer, computer-assisted semen analysis, hypoosmotic swelling test, cervical mucus penetration test, and flow cytometry, and advantages and disadvantages of each test were specified. This provides an insight into the different aspects of sperm functionality on which each spermicidal agent exerts its activity. A rationale of the best combination of in vitro spermicidal tests, with particular emphasis on a simple and efficient strategy that targets the complete fertility control, was explained.

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.

Does large loop excision of the transformation zone of the cervix predispose to the development of antisperm antibodies in women?

OBJECTIVE

To determine whether large loop excision of the transformation zone of the uterine cervix for cervical intraepithelial neoplasia predisposes to the development of female isoimmunity to human spermatozoa.

DESIGN

A prospective, controlled study.

SETTING

Colposcopy and Andrology units at the John Radclife and Churchill Hospitals, Oxford, United Kingdom.

INTERVENTIONS

Serum samples were collected from 33 women before large loop excision of the transformation zone of the cervix and repeated at a minimum time interval of 4 months after the procedure. Women were questioned regarding the procedure and subsequent reproductive function. A control population of 30 women not undergoing cervical surgery also underwent serial serum screening for antisperm antibodies.

MAIN OUTCOME MEASURE(S)

The detection of serum antisperm antibodies by flow cytometry.

RESULTS

None of the serum samples before large loop excision of the cervical transformation zone had clinically significant levels of antisperm antibodies. There was, however, a significant rise in antisperm antibody levels in women following large loop excision of the transformation zone. Apparent risk factors for the development of antisperm antibodies included a short duration of sexual abstinence and the use of nonbarrier contraception after surgery. There was no rise in antisperm antibody levels in the control population.

CONCLUSION

Large loop excision of the transformation zone of the cervix is a risk factor for the development of antisperm antibodies in women. Women should be advised to use barrier contraception or avoid sexual intercourse until complete healing of the cervix has occurred.

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.

Study of antisperm antibodies bound to the sperm cell surface and their relationship to circulating ASA

PROBLEM

Direct and indirect tests for antisperm antibody (ASA) detection are commonly used in laboratories for the diagnosis of male immunological infertility. Even though the two kinds of tests study the same immunological phenomena, frequently no perfect correlation is found even on large series of patients and with precise statistical models. The aim of the present investigation was to try to establish whether biological models can explain the antibody test results and if a predictive threshold can be established for expected positivity/negativity.

METHOD

The data relate to 667 patients, who were screened using the Direct Immunobead test (d-IBT) for ASA bound to the sperm surface and with the gelatin and tray agglutination test (GAT and TAT) in sera for circulating ASA. Correlation were studied and cases of no correlation were further analyzed.

RESULTS

The number of patients with a clinically significant positivity to d-IBT (binding percentage > or = 20%) was 134 (20.1% of total patients). The analysis of the results of direct and indirect tests shows that the discordances are due to differences in the Ig class of immunization or to the site of epitopes involved. In fact, as far the Ig class is concerned, if d-IBT shows a prevalent or exclusive IgG or IgA positivity, this results in a poor correlation between binding percentage to d-IBT and GAT-TAT titers. If both the Ig classes are involved, the level of positivity of the two kinds of test are strictly related. As far as the site of Ag-Ab reaction on the sperm surface is concerned, the wide immunization involving all the surface sperm antigens (mixed), shown by d-IBT, is related to higher indirect test titers.

CONCLUSION

Local and systemic antisperm immunizations are strictly related and a predictive threshold of expectation can be established to explain even apparently discordant direct and indirect results.