Immunologically reactive albumin-like protein in human testis and seminal plasma

Abstract

An immunologically reactive albumin-like protein (albumin) was localized, by an immunostaining technique, in the testis of infertile men (normal spermatogenesis, obstructive azoospermia) at the level of the Sertoli cells and in some cells of the germinal epithelium (secondary spermatocytes and early spermatids). No positive reaction was detectable in prepubertal testis. In vasectomized men, mean seminal albumin values were drastically reduced (by about 80%) in comparison to fertile controls, indicating a probable testicular origin. Mean seminal albumin values were also decreased in patients affected by azoospermia due to a seminiferous tubular lesion (about 40%) and in oligozoospermic patients (about 30%). In the same seminal samples transferrin, an index of Sertoli cell function, was also measured. Albumin and transferrin results were well correlated in the seminal plasma of each group (with the exception of vasectomized subjects), including a group of men with abnormally high concentrations of seminal transferrin. A weak correlation was found between seminal albumin and sperm count. We suggest that the presence of albumin in the human adult testis and in seminal plasma could be related to its ability to transport androgens.

Human serum albumin as a new interacting partner of prolactin inducible protein in human seminal plasma

“…These results suggest that during HSA-PIP complex formation, the secondary structure of HSA is partially disordered. Human seminal plasma is a rich source of HSA and it may originate from prostate [21], epididymis or testis [22]. Orlando et al (1988) correlated its presence in seminal fluid to its ability to transport androgens.…”

“…Human seminal plasma is a rich source of HSA and it may originate from prostate [21], epididymis or testis [22]. Orlando et al (1988) correlated its presence in seminal fluid to its ability to transport androgens. HSA can bind cholesterol efficiently and current understanding points towards a model in which cholesterol diffuses out of sperm spontaneously and presence of an acceptor in the medium results in net loss of this lipid from sperm membrane resulting in altered lipid composition favoring capacitation [23,24].…”

“…It has been suggested that albumin may influence sperm plasma membrane lipid composition through acting as a sterol acceptor [11]. Orlando et al (1988) have reported that the testis is the principal source of seminal albumin and its presence is correlated with its ability to transport the androgens. HSA is also supplied externally in sperm incubation media which support viability and motility of spermatozoa during capacitation in vitro [12].…”

Semen Traits and Seminal Plasma Biochemical Parameters in White Leghorn Layer Breeders

“…Several other proteins are produced by the Sertoli cells and can be divided into testis‐specific (inhibin) and serum‐like (e.g. transferrin, somatomedin‐C, ceruloplasmin and plasminogen activator) proteins (Orlando et al. 1988).…”

Effects of short-term high-dose testosterone propionate administration on medium molecular-weight proteins of human seminal plasma

“…The authors studied the following proteins: a 82-kDa protein identified as lactoferrin which derives from seminal vesicles (Hekman & Rumke 1968;Lilja et al, 1987;Autiero et al, 1991); a 50kDa protein and a 34-kDa protein identified respectively as the two reduced subunities of prostatic-acid phosphatase and prostate-specific antigen which are the two main prostatic products (Rui et al, 1984;Balerna et al, 1990;Autiero et al, 1991); and a 66 kDa protein identified as albumin which derives in seminal plasma from different sources such as prostate, seminal vesicles and testis (Rui et al, 1984;Orlando et al, 1988;Balerna et al, 1990;Autiero et al, 1991). Part of it is transferred also through circulation to the lower genital tract (Chard et al, 1991).…”