Changes in Localization of T Cell Subsets in the Ovarian Follicles during Follicular Growth and Ovulation in Hens

• Published in: The Journal of Poultry Science
• Main Authors: Kalpana Subedi, Yukinori Yoshimura
• Format: Article
• Language: English
• Published: Japan Poultry Science Association 2005-08-01
• Subjects: follicular growth; laying hens; ovarian follicles; t cell subsets
• Online Access: https://www.jstage.jst.go.jp/article/jpsa/42/3/42_3_215/_pdf/-char/en

Changes in the localization of helper and killer T cells (CD4+ and CD8+ T cells, respectively) in hen ovarian follicles with follicular growth and ovulation were examined in this experiment. White follicles (WF), the largest and the third largest preovulatory follicles (F1 and F3, respectively) and the largest postovulatory follicle (POF) were collected from birds after 5hrs of oviposition. Cryostat sections were prepared and immunostained for T cells using antibodies to CD4 (antigen of helper T cells) and CD8 (antigen of cytotoxic T cells). Populations of positive cells were observed under a light microscope and counted using a computer assisted image analyzer. The CD4+ and CD8+ T cells were localized in the theca interna and externa of all examined follicles. The frequencies of CD4+ and CD8+ T cells in the theca interna were similar among each type of follicles. The frequency of CD4+ T cells in the theca externa was significantly decreased in F3 and F1 compared with WF, with a further decrease in POF (P<0.05), and that of CD8+ T cells was lower in F3, F1 and POF than WF (P<0.01). The ratio of CD4+/CD8+ T cells in the theca interna was similar among each type of follicles but significantly lower in the theca externa of POF than WF, F3 and F1 (P<0.05). These results suggest that the T cell subsets, responsible for cell mediated immunity, are reserved in the theca layer of ovarian follicles, whereas their population decreases with follicular growth in theca externa.