Inflammatory response in the pig uterus induced by seminal plasma

Seminal plasma regulates endometrial cytokine expression, leukocyte recruitment and embryo development in the pig

“…Overt inflammatory indices subsided by day 5, perhaps because of an inhibitory role for increasing progesterone which acts to reduce expression of inflammatory mediators during early pregnancy in the mouse (Robertson et al 1996b) and human (Critchley et al 1996). The current study confirms and extends the previous observations (Bischof et al 1994, Engelhardt et al 1996 by clearly demonstrating that factors in seminal plasma, rather than the mating event itself, initiate the inflammatory cascade. Moreover, by quantifying the cellular changes, we have confirmed that both macrophages and MHC class II þ cells increase.…”

“…Most prevalent amongst the infiltrating cells were macrophages and MHC class II þ cells in the endometrium, and granulocytes in the luminal fluid. Previous studies in pigs have noted an increase in MHC class II þ cells in the subepithelial endometrial tissue after mating with intact or vasectomised boars (Bischof et al 1994, Engelhardt et al 1996). These authors also described a concurrent endometrial hypertrophy, consistent with our observations on uterine vascularity, luminal fluid content and weight.…”

“…Leukocytes, including macrophages and dendritic cells, neutrophils, eosinophils and lymphocytes are present in the pig endometrium where their numbers fluctuate over the course of the cycle and during pregnancy (Hussein et al 1983, King 1988, beginning early after natural mating with intact boars (Bischof et al 1995). Exposure to seminal plasma is implicated in eliciting leukocyte recruitment since qualitative observations show that natural mating with a vasectomised boar may increase the numbers of major histocompatibility complex (MHC) class II þ cells in the endometrium, accompanied by changes consistent with lymphocyte activation in draining lymph nodes (Bischof et al 1994). However, the possible impact of neuroendocrine stimulation as a consequence of the physical act of mating was not precluded in this experiment and the molecular mediators of the effects of seminal plasma were not investigated.…”

Reproductive performance and uterine prostaglandin secretion in gilts conditioned with dead semen and receiving dietary supplements of folic acid

“…Such a result suggests a thickening of the uterine wall. A similar observation was reported by Bischof et al (1994), along with proliferation of the uterine glands, 2 to 4 d after exposure to seminal plasma. They attribute their effect to the fact that seminal plasma would be the primary physiological and immunological stimulus initiating an inflammatory response, which in turn induced dynamic changes in the tissue and cellular components of the endometrium.…”

“…The potential stimulation of uterine immuno-protective activity by folic acid on uterine secretion may be lower in nulliparous than in multiparous sows because the uterus has not yet been sensitized with antigenic factors. In nulliparous sows, a pronounced immunological change in the uterus, such as up-regulation of major histocompatibility complex (MHC) class 2 and Interleukin 2 receptors, can be induced after uterine infusion with seminal plasma (Bischof et al 1994). The increased litter size after intrauterine infusion of dead semen (Murray and Grifo 1986), and seminal or sperm antigens (Murray et al 1983) before breeding has been attributed to a suppression and/or modulation of the uterine immune system.…”