Expression of novel pregnancy markers stimulated by bovine embryo at early diestrus

• Grant number: 20/11348-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2020
• End date: August 31, 2021
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Reproduction
• Principal Investigator: Guilherme Pugliesi
• Grantee: Pedro Pisani de Freitas
• Host Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 15/10606-9 - Innovations in the early pregnancy diagnosis in cattle, AP.JP

Abstract

The present proposal aims to determine which genes identified by transcriptomic analysis through RNASeq (Rocha et al., 2020) are stimulated by the bovine conceptus at the beginning of diestrus in two groups of immune cells from peripheral circulation, the PMNs (neutrophils, basophils and eosinophils) and PBMCs (monocytes and lymphocytes). These transcripts may present an earlier and more pronounced response to the interferon-tau stimulus to serve as a base to identify a marker of pregnancy status with a better accuracy compared to classic interferon-stimulated genes (ISG). For this, beef cows will be subjected to superovulation, artificial insemination and embryo collection on Day 7 ( Day 0 = day of estrus). At the moment of the embryo collection, blood samples (40 mL) will be collected for isolation of PMNs and PBMCs. The embryos collected will be evaluated, and those classified with excellent morphological quality will be cultivated for 12 hours and the conditioned culture medium will be added in culture of PMN and PBMCs collected from non-pregnant cow at early diestrus. The expression of the new transcripts identified in Experiment 1 of the Young Researcher project will be evaluated in cultured immune cells and in immune cells isolated from the blood samples collected in the moment of embryo collection compared to PMNs and PBMCs grown without embryo culture medium and isolated from non-inseminated females (control group). (AU)