Progression of Oocyte Maturation From Metaphase I to Metaphase II is disturbed by previous immunological interference with cumulus cell function

Abstract

The effects of an antibody preparation reacting with preovulatory mouse cumuli oophori (anticumulus Ig) on oocyte maturation in vivo and in vitro were studied. Continuous presence of anticumulus Ig in culture medium did not impair oocyte maturation in vitro. Similarly, no effect on oocyte maturation in vivo was observed when anticumulus Ig was given to females superovulated with pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG) at the time of hCG treatment. However, when administered earlier, anticumulus Ig brought about serious disturbances of oocyte meiotic competence, since only immature oocytes were ovulated after anticumulus Ig injection at the time of PMSG treatment and as much as 70% of the ovulated oocytes were immature when the antibody was applied 24 hr later. Previous absorption of anticumulus Ig with isolated cumulus cells removed the inhibitory effect of this preparation on oocyte meiotic competence to the same extent as absorption with whole cumuli oophori, despite the persistence of a strong reactivity of the cumulus cell-absorbed antibody preparations with the cumulus intercellular matrix. The ability of oocytes obtained from antibody-injected animals to mature in vitro was also considerably impaired when the injection was made at the time of PMSG treatment. In all cases the maturation defect concerned the progression of meiosis from metaphase I to metaphase II, while the ability of oocytes to undergo germinal vesicle breakdown (GVBD) was unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)

Evidence of new antigens in the mouse cumulus oophorus during preovulatory cumulus expansion

“…Complementing previous in vivo studies in mice (Tesarik et al, , 1991, we have evaluated the effects of anti-COC on murine in vitro fertilization (IVF). Anti-COC was active a t low doses in IVF, since preincubation with 5% anti-serum led to a very poor fertilization rate and fertilization was inhibited in a dose-dependent manner (Fig.…”

“…A recent analysis of oocyte maturation disturbance provoked by passive immunization of mice with our antibody (Tesarik et al, 1991) showed that mostly immature oocytes were ovulated after anti-COC injection at the time of PMSG treatment. The 2 different antifertility effects observed by passive immunization, i.e., impairment of oocyte maturation and inhibition of mature oocyte fertilization, might be related to antibodies directed against the cellular fraction and matrix components, respectively.…”

“…The presence of specific antigens in the preovulatory cumulus oophorus could be of importance for the development of contraceptive vaccines based on cumulus antigens. It has been shown recently that rabbit antiserum against the mouse cumulus-oocyte complexes (anti-COC) inhibited both oocyte maturation and fertilization performance of mature oocytes (Tesarik et al, , 1991. On the other hand, an antiserum raised against a cell-free preparation of the human cumulus intercellular matrix was previously reported to inhibit in vitro fertilization of human oocytes (Tesarik, 1989).…”

Localization and partial characterization of a rat ovarian granulose cell protein with a monoclonal antibody

“…It has been shown recently that the fully developed cumulus exerts two important biological roles. Before ovulation, it controls oocyte maturation, and after ovulation it participates in the complex mechanisms controlling the access of the fertilizing spermatozoon to the oocyte [26,27]. In this light Amiel et al [1] tested the effects of an antiserum against mouse cumulus-oocyte complexes (anti COC) on in vitro fertilization of mouse oocytes and results indicated the appearence of new antigens in mouse cumulus during preovulatory expansion.…”

“…This observation leads to the suggestion that the follicle exerts an inhibitory influence on the oocyte [29]. It has been shown recently that antiserum against the mouse cumulusoocyte complexes inhibited both the oocyte maturation and fertilization performance of mature oocytes [26,27]. In vivo, the growing oocyte is surrounded by follicular cells whose processes pass through the forming zona pellucida and terminate on the oocyte with gap junction; oocytes continue to grow in vitro only when oocyte-granulosa cell contacts are maintained [9].…”