IMMUNOHISTOCHEMISTRY OF PROSTASOMES FROM HUMAN SEMEN

BACKGROUND. To elucidate the origin of so-called ''prostasomes'' in hu man semen, a polyvalent rabbit antiserum was produced against a highly purified preparation of these secretory particles. METHODS. An immuno affinity selected fraction of the antiserum contained one antibody whi ch in Western blots of prostate extracts showed a 100 kDa band. RESULT S. Semithin sections processed for immunohistochemistry by using this immunoselected antibody presented a distinct immunoreaction at the api cal plasma membrane of secretory cells. The immunoreaction was not org an specific, but was present also in seminal vesicles, epididymis, sal ivary glands, and kidney. As spermatozoa present in epididymis and sem inal vesicles were likewise immunoreactive, a polytopic origin of the respective antigen was concluded. CONCLUSIONS. Prostatsomes therefore should rather be designated as ''seminosomes'' which more clearly refe rs to the composite origin of these particles. (C) 1997 Wiley-Liss, In c.