Infecção de Listeria spp. em células trofoblásticas bovinas

Abstract

Listeria monocytogenes is a Gram-positive, facultative intracellular and invasive bacterium that has tropism to the placenta, and causes fetal morbidity and mortality in several mammalian species. While infection by L. monocytogenes and L. ivanovii are known as an important cause of abortion and reproductive failure in cattle, the pathogenesis of maternal-fetal listeriosis in this specie is poorly known. This study used the bovine chorioallantoic membrane explant model to investigate the kinetics of L. monocytogenes, L. ivanovii and L. innocua infections in bovine trophoblastic cells for up to 8 hours post infection. L. monocytogenes and L. ivanovii were able to invade and multiply in trophoblastic cells without causing cell death or inducing expression of pro-inflammatory genes. Although L. innocua was unable to multiply in bovine trophoblastic cells, it induced transcription of the proinflammatory mediator CXCL6. This study demonstrated for the first time the susceptibility of bovine trophoblastic cells to L. monocytogenes and L. ivanovii infection. The bovine chorioallantoic membrane explant model proved to be a suitable tool for studying the molecular mechanisms of Listeria spp. pathogenesis in bovine trophoblastic cells, which may lead us to a better understanding of Listeria-induced abortion in cattle.