| Seminal plasma (SP) transforming growth factor beta-1 (TGFbeta-1) presumably is an immune modulator in mammalian female reproductive tract. Four experiments examined (1) distribution of TGFbeta-1 and associated molecules in sheep uterus shortly after breeding, (2) role of SP in stimulating uterine TGFbeta-1 as embryo enters the uterine horn, (3) SP TGFbeta-1 on gene expression of immune tolerance related factors at embryonic attachment, and (4) relationship of SP TGFbeta-1 and sperm characteristics in rams and bulls. Ewes were mounted (day 0) but not mated or were mated by intact or vasectomized rams or were inseminated with semen containing additional or less TGFbeta-1. Uterus was collected day 0, 2, 4, 6 or 22. Total and latent luminal TGFbeta-1 concentrations varied among days 0, 2, 4 and 6, and were affected by serum progesterone concentration; luminal active TGFbeta-1 appeared highest on day 4 and lowest on day 6. Tissue staining for TGFbeta-1 was strongest at estrus in endometrial epithelium, glands closer to lumen, endothelium, phagocytes and fibroblasts. TGFbeta-1 receptor type II was in myometrial blood vessel muscularis, phagocytes, and deep uterine gland epithelia. Decorin, which sequesters active TGFbeta-1, was in serosa and extracellular space surrounding myometrial muscle fibers and tunica adventitia. Shift in distribution of TGFbeta-1, its receptor, and decorin was observed with stronger immunostaining in luminal proximity on day 0 and 2. Content of TGFbeta-1 in tissue layers did not vary, and luminal and tissue concentrations did not differ due to SP. Thus, uterine TGFbeta-1 did not have SP origin. Further, SP TGFbeta-1 had no effect on expression of maternal immune tolerance factors, although expression of cell cycle and anti-cancerous-like genes were down-regulated in artificially inseminated ewes and more so in the group with less TGFbeta-1. Concentration of TGFbeta-1 in ram and bull SP was not correlated to sperm morphology or motility or TGFbeta-1 in blood (rams). In conclusion, location of TGFbeta-1 in uterus early after mating shifted, but TGFbeta-1 concentration was not dependent on SP. Gene expression at placental attachment was affected by SP TGFbeta-1 suggesting that SP TGFbeta-1, in conjunction with other SP components, has functions other than immuno-regulatory. |
