PRESENCE OF SYNAPTONEMAL COMPLEX PROTEIN-1 TRANSVERSAL FILAMENT-LIKE PROTEIN IN HUMAN PRIMARY SPERMATOCYTES

The synaptonemal complex (SC) is involved in the pairing of chromosome s during meiosis. We found that antibodies raised against a protein co mponent (P1) of the mouse synaptonemal complex, mouse SCP1, also ident ified the SC in human primary spermatocytes. Biopsies from 18 men pres ented with infertility were evaluated by light-field microscopy and gr ouped into five categories: normal spermatogenesis, Sertoli cell-only syndrome, meiotic disturbances, spermiogenic (i.e. differentiation) di sturbances, and other combined disturbances. In all the normal subject s the SCP1 antibody distinctly stained the synaptonemal complexes of p rimary spermatocytes, whereas Sertoli cells, spermatogonia or spermati ds were never stained. In three of the groups, which had germ cells bu t showed spermatogenic disturbances, the staining was similar to that seen in normal subjects. In sharp contrast to this, in sections from m en with Sertoli cell-only syndrome no specific staining was seen. This study demonstrates that a SCP1-related protein is also conserved in t he synaptonemal complex in meiotic cells from man. Further studies wil l reveal to what extent the absence or the non-functionality of SCP1 c ontributes to male infertility.