Modulation of Maternal Immune System During Pregnancy in the Cow

Abstract

Contents There is a molecular crosstalk between the trophoblast and maternal immune cells of bovine endometrium. The uterine cells are able to secrete cytokine/chemokines to either induce a suppressive environment for establishment of the pregnancy or to recruit immune cells to the endometrium to fight infections. Despite morphological differences between women and cows, mechanisms for immune tolerance during pregnancy seem to be conserved. Mechanisms for uterine immunesuppression in the cow include: reduced expression of major histocompatability proteins by the trophoblast; recruitment of macrophages to the pregnant endometrium; and modulation of immune‐related genes in response to the presence of the conceptus. Recently, an eGFP transgenic cloned embryo model developed by our group showed that there is modulation of foetal proteins expressed at the site of syncytium formation, suggesting that foetal cell can regulate not only by the secretion of specific factors such as interferon‐tau, but also by regulating their own protein expression to avoid excessive maternal recognition by the local immune system. Furthermore, foetal DNA can be detected in the maternal circulation; this may reflect the occurrence of an invasion of trophoblast cells and/or their fragment beyond the uterine basement membrane in the cow. In fact, the newly description of exosome release by the trophoblast cell suggests that could be a new fashion of maternal‐foetal communication at the placental barrier. Additionally, recent global transcriptome studies on bovine endometrium suggested that the immune system is aware, from an immunological point of view, of the presence of the foetus in the cow during early pregnancy.

Subcutaneous Immunization with Inactivated Bacterial Components and Purified Protein of Escherichia coli, Fusobacterium necrophorum and Trueperella pyogenes Prevents Puerperal Metritis in Holstein Dairy Cows

“…In the present study, intravaginal immunization was not effective in preventing uterine diseases, suggesting that mucosal immunization of the vagina, considering dose and composition used, does not affect the immunological status of the uterus. Nevertheless, it is important to highlight that the uterus is an immune tolerant environment during pregnancy [51], and this might have prevented the uterus to develop an immune response to the intravaginal vaccines. Further investigation is needed to evaluate if intravaginal vaccination administered prior to pregnancy would elicit a uterine immune response capable of prevent uterine diseases, and conclude if local synthesis of specific antibodies by the uterine mucosa is important for the prevention of puerperal metritis and endometritis in heifers.…”

Exosomes: an overview of biogenesis, composition and role in ovarian cancer

“…Presently, ~2,000 microRNAs have been described in human [78] microRNAs have been reported to play important role in in cellular and developmental processes, including developmental timing, organ development, differentiation, proliferation, apoptosis and immune regulation [67]. Recently, Taylor and his colleagues reported the presence of diagnostic miRNAs from EpCAM-positive exosomes from ovarian cancer patients’ serum [12].…”

Developing a conceptual model of possible benefits of condensed tannins for ruminant production

“…Immune-physiological reproductive evidence suggests that increased numbers of γδ T-cells in endometrial luminal epithelium are not only dependent upon conceptus stimulus (Tekin and Hansen, 2004) but also on systemic signals (i.e. maternal blood circulation; Majewski et al, 2001;Oliveira et al, 2012). In immune-modulating in vitro assays (Holderness et al, 2007) with apple CT (i.e.…”

“…It is also likely that protein mediators (i.e. limphokines) produced by epithelial uterine lymphocytes induce regulatory dynamics on IFN-τ and IFN-γ (Oliveira et al, 2012). However, although the function of γδ T-lymphocyte on early maternal − embryonic and embryonic − foetal interfaces is not clear, Holderness et al (2007) and Jutila et al (2008) suggested that CT (i.e.…”