RECOGNITION OF SURFACE-ANTIGENS ON SPERMATOZOA OF THE COMMON CARP (CYPRINUS-CARPIO L, TELEOSTEI) USING MONOCLONAL-ANTIBODIES AND SCANNING ELECTRON-MICROSCOPY

The distribution of antigenic determinants, recognized by seven anti-c arp spermatozoa monoclonal antibodies (MAbs) and two anti-carp spermat ogonia MAbs were studied using fresh, unfixed carp spermatozoa. The lo cation of the antigenic determinants was analysed in light- and in sca nning electron microscopy, in the latter with the backscattered imagin g mode. With all seven anti-carp spermatozoa MAbs a similar regular di stribution of the immuno-gold labeling was present on heads, midpieces and tails of carp spermatozoa, whereas with the anti-carp spermatogon ia MAbs only low or no labeling was observed. The regular distribution of antigenic determinants, as observed with the anti-spermatozoa MAbs in carp, is in agreement with data on agglutination of spermatozoa by autoantibodies in Salmo gairdneri and data on distribution of antigen ic sites on spermatozoa in Xenopus laevis. It differs from data in mam mals in which the presence of specialized domains on spermatozoa was s hown. These results are discussed.