title: Immunolocalization of sperm protein 17 in human testis and ejaculated spermatozoa.
abstract: Sperm protein 17 (Sp17) is a highly conserved mammalian protein whose primary function is still poorly understood. Immunohistochemistry (IHC) in the human testis reveals the presence of Sp17 in some spermatocytes and abundantly in spermatids. All spermatogonia, Sertoli cells, and Leydig cells appear to be immunonegative for Sp17, whereas some interstitial cells are immunopositive. IHC recognized two distinct populations (immunopositive or not for Sp17) in the ejaculated spermatozoa. Although it will be necessary to clarify why some ejaculated spermatozoa do not contain Sp17, its distribution suggests that this protein may be associated with some phases of germinal cell differentiation.
authors.affiliation: Scientific Direction, Istituto Clinico Humanitas, Rozzano, Milan, Italy. fabio.grizzi@humanitas.it
authors.forename: Fabio
authors.initials: F
authors.lastname: Grizzi
authors.forename: Maurizio
authors.initials: M
authors.lastname: Chiriva-Internati
authors.forename: Barbara
authors.initials: B
authors.lastname: Franceschini
authors.forename: Paul L
authors.initials: PL
authors.lastname: Hermonat
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Soda
authors.forename: Seah H
authors.initials: SH
authors.lastname: Lim
authors.forename: Nicola
authors.initials: N
authors.lastname: Dioguardi
mesh_terms: D000954:Antigens, Surface; D002148:Calmodulin-Binding Proteins; D002352:Carrier Proteins / Q000378:metabolism*; D004542:Ejaculation; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008565:Membrane Proteins; D009928:Organ Specificity; D013094:Spermatozoa / Q000378:metabolism*; D013737:Testis / Q000166:cytology / Q000378:metabolism*
chemical_list: D000954:Antigens, Surface; D002148:Calmodulin-Binding Proteins; D002352:Carrier Proteins; D008565:Membrane Proteins; C090172:SPA17 protein, human