Revisión de la patogénesis molecular del aborto por Brucella

C.A. Rossetti

doi:10.30972/vet.3527875

Authors

C.A. Rossetti Instituto de Patobiología.Instituto de Patobiología Veterinaria https://orcid.org/0000-0002-6932-2521

DOI:

https://doi.org/10.30972/vet.3527875

Keywords:

Tophoblasts, Cytokines, Hormones, Vaccines, Infection models

Abstract

Brucellosis is a global chronic zoonotic infectious disease caused by bacteria of the genus Brucella spp. It causes economic losses in livestock and public health problem. Abortion is the main clinical sign and is the most important vehicle for dissemination and maintenance of the disease. However, knowledge of the molecular mechanisms of the abortion is very limited. Brucella spp. shows a special tropism for the pregnant uterus in the last third of the gestation, where it survives and replicates inside the trophoblasts. The high number of bacteria within trophoblasts induces apoptosis of infected cells due to endoplasmic reticulum stress. The massive destruction of trophoblasts leads to fibrino-necrotic placentitis, which prevents nutritional and gas exchange between the mother and the fetus. Interruption of pregnancy occurs when healthy placentomes are not sufficient to maintain the gestation. The interaction between Brucella and trophoblasts has not been studied in detail, and many scenarios of this interaction are inferred from observations in other cells. This article discusses the Brucella virulence factors that are part of the adhesion, invasion and intratrophoblastic replication of the bacteria, and the local consequences that occur, together with the preventive action of the vaccines on the abortion. Finally, several available in vivo and ex vivo models of study that have not been fully explored and that could help obtain more information about the molecular pathogenesis of Brucella abortion are presented.

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References

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