Journal of Andrology, Vol. 25, No. 6, November/December 2004
Copyright © American Society of Andrology
Identification and Characterization of an Antigen Recognized by Monoclonal Antibody TRA 54 in Mouse Epididymis and Vas Deferens
KÉLEN F. ARROTÉIA*,
PAULO P. JOAZEIRO*,
ÁUREO T. YAMADA*,
HIROMITSU TANAKA
,
YOSHITAKE NISHIMUNE
AND
LUÍS. A. V. PEREIRA*
From the * Laboratory of Cytochemistry and
Immunocytochemistry, Department of Histology and Embryology, Institute of
Biology, State University of Campinas (UNICAMP), Campinas, SP, Brazil; and the
Institute for Microbial Diseases, Osaka
University, Suita, Osaka, Japan.
|
Correspondence to: Dr Luís Antonio Violin Pereira, Department of
Histology and Embryology, Institute of Biology, State University of Campinas
(UNICAMP), PO Box 6109, 13083-970, Campinas, SP, Brazil (e-mail:
lviolin{at}unicamp.br). |
Spermatozoa in testicular fluid are known to have weak forward motility and
cannot fertilize eggs. The epididymis is known to participate in sperm
maturation leading fertilization, but little is known about the specific
epididymal molecules involved in the modification of sperm. In this study, we
characterized the new pattern of expression of an antigen previously
identified in testicular germ cells by monoclonal antibody (mAb) TRA 54. This
antigen is expressed in epididymal and vas deferens epithelial cells in mice
older than 24 days but not during younger developmental stages. Evaluation by
immunohistochemistry shows that antigen expression is limited to the cytoplasm
of a specific cell population of epithelia along the epididymal regions and
vas deferens of adult mice. The molecules synthesized and released by
epididymal and vas deferens epithelia into their lumen seem to bind on
spermatozoa moving down through the ducts. Immunoblot analysis showed that the
molecules recognized by mAb TRA 54 in testis and epididymis were similar and
share a common epitope involving carbohydrate domains. Interestingly, the
antigens identified in epididymal and vas deferens epithelial cells were
expressed independently of testicular germ cells and are produced in an
androgen-dependent manner. Finally, the molecules recognized by mAb TRA 54
seem to play an important role in spermatogenesis, as well as in epididymal
function related to spermatozoa maturation and ability to fertilize.
Key words: Testis, sperm antigens, cryptorchidism, castration, testosterone replacement
Copyright © 2004 by The American Society of Andrology.