Female Reproductive System and Immunology

Abstract

Health of the reproductive organs is essential for formation and production of high quality and hygienic eggs. It is of importance to review the structures and functions of female reproductive system for better understanding of the mechanism by which the eggs are formed. The unique functions of ovarian cells for follicular growth and differentiation as well as steroidogenesis and oocyte maturation are regulated by gonadotropins and gonadal steroids. The oviduct is responsible for egg formation, while the unique function to store sperms for a prolonged period takes place in the specific tissue of this organ. The unique innate and adaptive immuno-defense systems that play essential role to prevent infection are developed in the ovary and oviduct. Toll-like receptors (TLRs) that recognize the molecular pattern of microbes and initiate the immunoresponse are expressed in those organs. Avian β-defensins (AvBDs), a member of antimicrobial peptides, are synthesized by the ovarian and oviductal cells. Challenge of those cells by TLR ligands upregulates the expression of proinflammatory cytokines, which in turn stimulate the expression of AvBDs. The adaptive immune system in the ovary and oviduct is also unique, since the migration of lymphocytes is enhanced by estrogens. In contrast to the development of immuno-defense system, spontaneous ovarian cancer and uterine fibroids appear more frequently in chickens than in mammals, and thus chickens could be used as a model for studying these diseases. Thus the avian reproductive organs have unique functions not only for egg formation but also for the immuno-defense system, which is essential for prevention of infection and production of hygienic eggs.

miR‐17‐5p affects porcine granulosa cell growth and oestradiol synthesis by targeting E2F1 gene

“…Folliculogenesis is controlled by several kinds of molecules including hormones, cytokines and growth factors. A series of continuous developmental processes of follicles are undulating with the oestrous cycle, mainly undergoing three stages of initiation, growth and maturation (Yoshimura & Barua, ). Granulosa cells are an important component of pig follicles, and their growth and morphological functions change along with the whole development process of follicles.…”

Immune-Endocrine Interactions in the Fish Gonad during Infection: An Open Door to Vertical Transmission

“…The presence in the follicles of antigen-presenting cells and T and B lymphocytes is related with sexual maturation and probably with estrogen levels. Interestingly, these cells increase in number upon an infection [70]. Similarly, in the elasmobranch fish Little skate (Leucoraja erinacea) ovary, direct contact between leucocytes and the follicle wall as well as between the steroidogenic theca and granulosa cells has been demonstrated [71].…”

“…Several types of resident leucocytes are also present in the ovary of mammals, where they are involved in ovulation and in the development of the corpus luteum (see for review [20]. In hen (Gallus gallus) ovaries, macrophages are present in the theca layer and are able to phagocytose particles, being the first line of defense of pre-and post-ovulatory follicles [70]. Moreover, follicular cells (both theca and granulose cells) express TLRs that induce an innate immune response, including the expression of several β-defensins, which are important AMPs [70].…”

“…In hen (Gallus gallus) ovaries, macrophages are present in the theca layer and are able to phagocytose particles, being the first line of defense of pre-and post-ovulatory follicles [70]. Moreover, follicular cells (both theca and granulose cells) express TLRs that induce an innate immune response, including the expression of several β-defensins, which are important AMPs [70]. The presence in the follicles of antigen-presenting cells and T and B lymphocytes is related with sexual maturation and probably with estrogen levels.…”

Gallus gallus domesticus: immune system and its potential for generationof immunobiologics

“…Influx of immune cells increases with hen maturity and decreases with aging. The ovary's parenchyma and the oviduct's lamina propria express TLR (Toll-like receptor) molecules, triggering the production of pro-inflammatory cytokines and chemokines, and defensin molecules (YOSHIMuRa & BaRua, 2017).…”