Campylobacter fetus Induced Proinflammatory Response in Bovine Endometrial Epithelial Cells

Abstract

Campylobacter fetus subsp. fetus is the causal agent of sporadic abortion in bovines and infertility that produces economic losses in livestock. In many infectious diseases, the immune response has an important role in limiting the invasion and proliferation of bacterial patho¬gens. Innate immune sensing of microorganisms is mediated by pattern-recognition receptors (PRRs) that identify pathogen-associated molecular patterns (PAMPs) and induces the secretion of several proinflammatory cytokines, like IL-1β, TNF-α, and IL-8. In this study, the expression of IL-1β, TNF-α, IL-8, and IFN-γ in bovine endometrial epithelial cells infected with C. fetus and Salmonella Typhimurium (a bacterial invasion control) was analyzed. The results showed that expression levels of IL-1β and IL-8 were high at the beginning of the infection and decreased throughout the intracellular period. Unlike in this same assay, the expression levels of IFN-γ increased through time and reached the highest peak at 4 hours post infection. In cells infected with S. Typhimurium, the results showed that IL8 expression levels were highly induced by infection but not IFN-γ. In cells infected with S. Typhimurium or C. fetus subsp. fetus, the results showed that TNF-α expression did not show any change during infection. A cytoskeleton inhibition assay was performed to determine if cytokine expression was modified by C. fetus subsp. fetus intracellular invasion. IL-1β and IL-8 expression were downregulated when an intracellular invasion was avoided. The results obtained in this study suggest that bovine endometrial epithelial cells could recognize C. fetus subsp. fetus resulting in early proinflammatory response.

Frecuencia de Campylobacter fetus en bovinos sementales en la zona centro de Tamaulipas México

“…La enfermedad es considerada de reporte obligatorio, incluída en la Lista B de las enfermedades de los animales terrestres según la Organización Mundial de Salud Animal (OMSA), antes OIE (Tshipamba et al, 2020). En rumiantes Cff se ha demostrado que el patógeno afecta el sistema entérico, especialmente el intestino (Li et al, 2022), por otro lado, los toros con Cfv son reservorio porque las bacterias viven y se adaptan en los quistes prepuciales, mientras que en las vacas las colonizaciones son en vagina, cuello uterino y útero (Cagnoli et al, 2020y Lúcio et al, 2019 induciendo procesos proinflamatorios (Campos-Múzquez et al, 2021) debido a la internalización en células del epitelio endometrial (Campos-Múzquez et al, 2019) provocando abortos (Clune et al, 2022); C. fetus también puede afectar a humanos y se ha reportado induciendo infecciones sistémicas (Adhikari et al, 2022) endocarditis (Lynch et al, 2022 y meningitis (Fernández et al, 2022). El aislamiento bacteriológico y la utilización de pruebas bioquímicas juegan un papel importante para la identificación de C. fetus y la diferenciación entre Cff y Cfv, ya que se consideran el estándar de oro, sin embargo, la implementación de estas técnicas de cultivo es difícil, ya que Campylobacter requiere condiciones de cultivo in vitro más exigentes que otros géneros bacterianos, además, el cultivo es pobre en confiabilidad y reproducibilidad (Iraola et al, 2016).…”