How Campylobacter jejuni survives within cells
Campylobacter jejuni is one of the major causes of infectious diarrhoea world-wide, although relatively little is know about its mechanisms of pathogenicity. After infection through the oral route, this bacterium invades the cells of the intestinal epithelium, a property that is important for its ability to cause disease. Usually, bacteria and other material entering the cell are moved to compartments called lysosomes, where an acidic mix of enzymes digests them. This study shows that C. jejuni can survive within intestinal epithelial cells by avoiding delivery to lysosomes. In contrast, in macrophages, which are specialized cells with the capacity to engulf and kill bacteria, C. jejuni cannot avoid delivery into lysosomes and consequently is rapidly killed. However, recovery of intracellular bacteria required pre-culturing under oxygen-limiting conditions, suggesting that C. jejuni undergoes significant physiological changes within the intracellular environment. The authors found that in epithelial cells the C. jejuni containing vacuole deviates from the usual endocytic pathway after a unique caveolae-dependent entry pathway, thus avoiding delivery into lysosomes. In contrast, in macrophages, C. jejuni is delivered to lysosomes and consequently is rapidly killed. Taken together, these studies indicate that C. jejuni has evolved specific adaptations to survive within host cells and help explain an important virulence attribute of C. jejuni.
Related:
- Campylobacter jejuni
- Listeria monocytogenes replication in macrophage vacuoles
- Legionnaires Disease – the invaders from within
Tags: Bacteria, Biology, Health, Medicine, Microbiology, Science
