Effects of Age and Gonadal Steroids on the Localization of Antigen Presenting Cells in the Epididymis of the Male Chicken, Gallus domesticus

Abstract

Abstract. The goal of this study was to localize antigen presenting cells (APC), which may play roles in defense against pathogens and fertility, and examine the effects of age and gonadal steroids on their population in the rooster epididymis. Healthy White Leghorn male birds (immature 60-day-old birds; matured 150-, 330-, and 550-day-old), and immature birds treated with testosterone propionate (TP) or estradiol benzoate (EB) for 3 or 6 days were used. Cryostat sections of the epididymis and ductus deference were immunostained for Ia to identify APC. RT-PCR was performed to confirm the expression of major histocompatibility complex class II (MHC class II) mRNA in the epididymis. Ia + cells were localized in the surface epithelium and subepithelial layer of the ductules and occasionally in the luminal content of the epididymis and ductus deference. RT-PCR analysis confirmed expression of MHC class II mRNA in the epididymis, ductus deferens, testis, and spleen. The frequency of Ia + cells in the subepithelial layer was significantly greater in the proximal efferent ductules than in the other two types of ductules in the epididymis of 550-day-old birds. Although there were no significant differences in the frequencies in the subepithelial layer of the proximal efferent ductules between 60-and 150-day-old birds, the frequencies were significantly greater in 330-and 550-day-old birds than in 60-day-old birds. The frequencies of Ia + cells in the ductus deferences was increased in the 150-day-old birds compared with the 60-day-old birds, with a larger increase in 330-and 550-day-old birds. The Ia + cell frequency was significantly increased by EB-injection, but not by TP-injection, on Days 3 and 6 of injection compared with Day 0. These results suggest that the population of APC in the epididymis increases with age after sexual maturation, and estrogen may be one of the factors involved in induction of Ia + cells.

Epididymal lithiasis in roosters: In the middle of the way there was a stone

“…The autoimmunity hypothesis states that the blood-lumen barrier of the efferent ductules in affected roosters is somehow disrupted or at least leakier than in non-affected animals (Jackson et al, 2006). This leakage may result in the passage of luminal content to the connective tissue and the subsequent stimulation of the interstitial immune cells, including the antigen presenting cells and CD4 + and CD8 + T cells that are abundant in the areas adjacent to the efferent ductules (Yoshimura et al, 2005(Yoshimura et al, , 2006. These cells are the putative modulators of a local immune response against luminal antigens that results in the recruitment of other immune cells and in the production of antibodies that are secreted to the lumen.…”