Antisperm antibodies and sperm motility: a study using timed exposure photomicrography

Infertility due to antisperm antibodies

Immunoinfertility is an important problem, involving a significant number of infertile couples. Although the presence of antibodies on sperm has better prognostic value than those in serum or seminal plasma, it may not be the sole authentic evidence of immunoinfertility. Infertility from antisperm antibodies is likely only when they bind to a relevant sperm antigen involved in a specific fertility function. The variance in functional deficits seen in immunologic infertility is most likely related to antibodies directed at different sperm antigens or different class, subclass, or isotypes. Antibodies to FA-1 seem to be of significant importance in human immunoinfertility. In approaching couples with infertility, a high index of suspicion for antibodies is necessary to avoid misdiagnosis. In the optimal situation, all semen analyses should be screened for sperm-bound antibodies, but if this is impractical, testing should be performed on high-risk individuals (Table I). In couples in which the man has sperm-bound antibodies, and in whom there is no identifiable female factor, treatment should be instituted. Most treatments for immunoinfertility have been disappointing because of poor results, adverse effects, or high cost. Corticosteroid therapy has shown some promise in published reports (mostly poorly designed studies), but increase in pregnancy rate is modest and adverse effects may be significant. In our opinion, informed consent should be documented prior to institution of corticosteroid therapy, and subjects should be closely monitored. Advanced reproductive technologies offer a higher safety profile, and, with increasing technology, higher pregnancy rates. We recommend progressing from "low-tech" procedures, such as IUI and reserving the higher level procedures, such as IVF and ICSI, for those couples in whom pregnancy does not occur. The highest level reproductive technologies give the best current prospects for pregnancy in patients with this difficult problem but also are invasive and costly. It is hoped that further work in the laboratory will give rise to newer, safer, and less expensive effective treatments in the very near future.

The effect of pentoxifylline on in-vitro fertilization in the presence of anti-sperm antibodies

In cases of severe immunological male-factor infertility, impairment of spermatozoal motility and of acrosome reaction resulting in reduced fertilization capacity have been described by several authors. The present study investigated the use of pentoxifylline in enhancing in-vitro fertilization (IVF) in the presence of anti-sperm antibodies. Thirty-seven IVF cycles were conducted in 28 different couples suffering from immunological male-factor infertility with at least 50% antibody-coated spermatozoa. Sibling oocytes were inseminated at random with spermatozoa incubated with or without 3.6 mM pentoxifylline after selection by a Percoll gradient. No difference in motility of the final sperm preparations was observed prior to insemination. Fertilization rate, cleavage rate and embryo quality were similar in both treatment and control groups. Nine out of ten pregnancies were achieved after the replacement of embryos both from the treatment and control group. Although pentoxifylline is known to enhance motility in-vitro and to promote induced acrosomal loss, its indiscriminate use failed to improve IVF performance in patients with anti-sperm antibodies. Further research may be necessary in order to elucidate whether a given subpopulation of these patients may benefit from a selective application of pentoxifylline.

Antibodies to human seminal plasma inhibin adversely affect sperm function parameters

Polyclonal antibodies to intact inhibin (94 amino acids, R-94, 10.5 kDa) and its sequence specific synthetic fragments (R-9, R-17) were evaluated for their effect on various physical and biochemical parameters of sperm function. Intact inhibit had maximum deleterious effect on quantitative motility and mean forward progression of spermatozoa. Antibodies had no effect on sperm fructolysis and sperm nuclear chromatin decondensation reaction. Sperm plasma membrane was damaged in antibodies treated spermatozoa as evidenced by hypoosmotic swelling test and sperm lipid peroxidation reaction.

Sperm function and its manipulation for microassisted fertilization

Comprehension of the intricate complexities of sperm function is clearly crucial to the success of attempts to manipulate it for the purposes of assisted conception. This is particularly important when considering various procedures for microassisted fertilization since these bypass critical physiological events that are mandatory for normal fertilization, to varying degrees. Methylxanthine derivatives such as pentoxifylline are useful agents for the management of oligoasthenozoospermic patients. This is particularly so for procedures such as SUZI where adequate motility of spermatozoa injected into the perivitelline space is crucial for fusion with the vitelline membrane to achieve fertilization. The generation of minute concentrations of reactive oxygen species in vitro may prove to be a valuable technique in this respect, in the light of recent evidence for their involvement in capacitation and hyperactivation. Induction of the acrosome reaction by non-invasive, non-toxic agents should markedly improve success rates for microassisted fertilization. Acrosin appears to play a central role in this and, therefore, it would seem prudent to monitor levels of acrosin activity in samples of spermatozoa used in assisted conception procedures. With respect to microassisted fertilization, the potential to select recently acrosome-reacted spermatozoa coated by activated acrosin promises to be a major improvement. Current methods employed for determination of the fertilization potential of spermatozoa are clearly inadequate (Polansky and Lamb, 1988; Aitken, 1990). In fact, the prevailing evidence suggests that no single parameter of sperm function reflects this potential (Zaneveld and Jeyendran, 1988). Therefore, we have both a scientific and a moral responsibility to investigate these processes further. Subsequently, we should be in a position to identify individual gametes with the potential for fertilization and so utilize procedures that result in maximal fertilization rates with minimal risk of polyploidy or abnormality.

Effect of sperm-associated antibodies on the dynamics of sperm movement and on the acrosome reaction of human spermatozoa

Anti-sperm antibodies were eluted from the sperm cell fraction of autoimmune human ejaculates and transferred onto normal motile spermatozoa. The movement and the acrosomal status of these antibody-coated spermatozoa were evaluated after incubation in a capacitating medium. The amplitude of lateral head displacement (ALH) and the straight line velocity (VSL) were analyzed using an HTM automated motility analyser. Acrosomal loss was monitored by an FITC-conjugated lectin binding technique. During the 6-h incubation in BWW-BSA medium, antibody-free and antibody-coated spermatozoa exhibited significant changes of ALH and VSL distribution that evolved differently in the two populations. The dynamics of sperm movement in control spermatozoa were apparently modified by the presence of antibodies on the sperm membrane. The low percentage of spontaneous acrosomal loss obtained in control populations, even after 20 h of incubation, was not modified by the presence of antibodies on spermatozoa. However, the same antibodies decreased the acrosomal loss induced by a calcium ionophore after 3 h of incubation in capacitating conditions. These results suggest that sperm capacitation and acrosome reaction, considered as essential for successful fertilization, can be altered by antisperm antibodies present on human ejaculated spermatozoa.

Effect of isotypes of antisperm antibodies on semen quality

A direct immunobead test (IBT) was performed on 233 men who attended an immunological centre. Thirty-four (14.6%) of these men were found to be positive (greater than 20% binding) for antisperm antibodies (ASA). IgA, IgG and IgM were the most common sperm-associated immunoglobulins. In 50% of men with ASA asthenozoospermia, teratozoospermia, leukocytospermia or hypofunction of the seminal vesicles was observed. Semen parameters were altered most frequently when IgM was present in association with IgA and/or IgG. This suggests that there is an active inflammatory process in the reproductive tract, as evidenced by leukocytospermia, and this could be responsible for the abnormal semen parameters. ASA generation could be a consequence of this process rather than being the cause of the abnormal semen quality. If ASA do affect fertility, this could take place in the female reproductive tract.

Etiology of severe asthenozoospermia and fertility prognosis. A screening of 5216 semen analyses

A review of n = 5216 semen analyses performed in our two Clinics from January 1986 to December 1989 allowed to identify n = 35 patients whose sperm had constantly very low motility (less than 5% progressive motile gametes in three subsequent analyses; necrozoospermia cases were excluded from this study). This apparently rare but severe anomaly was found to be associated not only with ultrastructural anomalies (n = 18), but also with positive seminal bacteriology (n = 8) or the presence of antisperm antibodies (n = 2). In eight cases the cause(s) for this constant asthenozoospermia remained obscure. The fertility potential of the men affected was followed-up and is discussed in relation to their anamnesis, physical exam and seminal characteristics.