Modulation of genes stimulated by interferon-tau secreted by the bovine conceptus into immune cells

Abstract

The development of new technologies to reliably detect pregnancy before the21st day after insemination would allow the opportunity for a new service at the nextestrus and could improve reproductive performance and profitability for commercialdairy and beef farms. Thus, the quantification of genes stimulated by interferon-Ä(ISG) in peripheral blood leukocytes and Doppler ultrasonography of the corpusluteum (CL) were tested by our group as early methods of pregnancy diagnosis. Although the assessment of luteolysis by Doppler ultrasonography is an excellentpregnancy predictor, it is not efficient in monitoring the viability of the conceptus andin predicting embryonic mortality between 20 and 30 days in cattle with active CL. Furthermore, the proportion of false-negative results is still not adequate for the useof ISG expression as an accurate and viable method for detecting pregnancy beforethe 20th day. Therefore, a better understanding of the basic events involved inmodulating the immune system in early pregnancy is the first step towardsdiscovering new biomarkers for earlier pregnancy detection than traditionalmethodologies. Therefore, our main objective with the present study is to understandthe direct and indirect response of immune cells to conceptus signaling during theearly stages of pregnancy in bovine females using an in vitro study model. To thisend, the profile of classic ISGs and new potential pregnancy markers involved in theuterine and peripheral immune response will be determined using an in vitro immunecell culture system associated with treatments with uterine flush (UF) and exogenousIFN-Ä. We anticipate that understanding the response of immune cells circulating tothe conceptus during days 15 and 20 of pregnancy has the potential to result in thediscovery of new pregnancy markers that can be determined in peripheral blood orimmune cells. The new knowledge and innovative methods proposed here will serveas a basis for the development of new technologies for diagnosing pregnancy incattle.