Lectin-binding sites in testis of men with acrosomeless round-headed spermatozoa

We report herein about lectin histochemistry of seminiferous epithelia in two infertile men with exlusely acrosomeless round-headed spermatozoa. FITC-conjugated lectins (ConA, PNA, RCA II, WGA) have been employed on tissue sections of Bouin fixed testicular biopsies. RCA II gave a dot-like fluorescence of the acrosomal region and WGA gave a cap-like acrosomal fluorescence of spermatids. PNA-a marker of acrosomal differentiation-failed to stain spermatids. The binding of ConA to germ cells was not influenced by this syndrome. In conclusion, the syndrome of acrosomeless round-headed spermatozoa is associated with selective perturbations of testicular lectin-binding sites. They might contribute of the inability of sperm cells to adhere to and penetrate into ova.

Morphological defects of the acrosome in boar spermatozoa

Morphological examination of semen from 17 boars of five breeds showed the presence of acrosome defects in 11 boars from four breeds. Two distinct types were seen; 'knobbed' sperm (type 1), of which two forms were found to be present by electron microscopy, and an uneven swellling of part of the acrosome (type 2) whose contents consisted of cytoplasmic and membrane-like material. The incidence of 'knobbed' sperm ranged from 0.2 to 6.3 per cent. Type 2 abnormalities were seen in only two boars, at 0.66 and 1.33 per cent.

Male infertility associated with round-headed acrosomeless spermatozoa

The properties of spermatozoa with round head syndrome in four unrelated patients are reported. The findings were as follows: (1) Electron microscopy demonstrated that all spermatozoa lacked an acrosome and postacrosomal sheath. (2) Acrosin activity was only 1% to 6% of that found in sperm obtained from fertile donors. (3) Phospholipase A2 activity was not significantly different from that of spermatozoa from donors of unknown fertility. (4) Electrophoresis of whole sperm extracts revealed deficiencies in major protein bands. (5) The round-headed spermatozoa failed to bind or penetrate the vitellus in the egg penetration test. (6) The rates of chemically induced nuclear chromatin decondensation of round-headed spermatozoa suggest that the acrosome content is not involved in this process.

Immunocytochemistry and sperm pathology

In this paper the Authors describe the localization of some significative proteins (acrosin, actin, tubulin, vimentin) detected by immunocytochemical methods in human infertile spermatozoa and correlate their distribution with the ultrastructural characteristics of the same spermatozoa, in order to clarify the structural bases of infertility.