PROBLEM: Uterine-derived factors are required for optimal conceptus development and secretion of the maternal recognition of pregnancy factor, interferon-tau (IFN-tau). Identifying these factors may lead to the development of schemes for increasing pregnancy success in cattle. METHOD OF STUDY: The objectives were to examine the effects of granulocyte-macrophage colony-stimulating-factor (GM-CSF) on trophectoderm proliferation rates and IFN-tau production, and verify the appropriateness of using an in vitro model of bovine trophectoderm (CT-1 cell). RESULTS: Rate of [(3)H]-thymidine incorporation into DNA was increased by supplementation of CT-1 medium with 10 or 100 ng/mL porcine (po) GM-CSF. GM-CSF supplementation to CT-1 medium also increased IFN-tau secretion. When results were normalized to account for number of CT-1 cells, 10 and 100 ng/mL poGM-CSF increased antiviral activity and IFN-tau concentrations (using an IFN-tau-specific enzyme-linked immunosorbent assay) in CT-1 conditioned medium compared with controls. CONCLUSIONS: These findings indicate that GM-CSF increases proliferation and IFN-tau production in bovine trophectoderm.
PROBLEM: Uterine-derived factors are required for optimal conceptus development and secretion of the maternal recognition of pregnancy factor, interferon-tau (IFN-tau). Identifying these factors may lead to the development of schemes for increasing pregnancy success in cattle. METHOD OF STUDY: The objectives were to examine the effects of granulocyte-macrophage colony-stimulating-factor (GM-CSF) on trophectoderm proliferation rates and IFN-tau production, and verify the appropriateness of using an in vitro model of bovine trophectoderm (CT-1 cell). RESULTS: Rate of [(3)H]-thymidine incorporation into DNA was increased by supplementation of CT-1 medium with 10 or 100 ng/mL porcine (po) GM-CSF. GM-CSF supplementation to CT-1 medium also increased IFN-tau secretion. When results were normalized to account for number of CT-1 cells, 10 and 100 ng/mL poGM-CSF increased antiviral activity and IFN-tau concentrations (using an IFN-tau-specific enzyme-linked immunosorbent assay) in CT-1 conditioned medium compared with controls. CONCLUSIONS: These findings indicate that GM-CSF increases proliferation and IFN-tau production in bovine trophectoderm.