A defined bacterial consortium and spatial transcriptomics highlight the complex interaction between Campylobacter...

Area of Science:

• Microbiology
• Immunology
• Gastroenterology

Background:

• The intestinal microbiota significantly impacts host susceptibility to Campylobacter jejuni (C. jejuni) infections.
• The specific roles of individual gut bacteria in C. jejuni-mediated host responses remain largely undefined.

Purpose of the Study:

• To investigate the influence of a defined bacterial consortium on host responses to C. jejuni infection.
• To delineate the interplay between specific gut bacteria, C. jejuni, and host immunity using a controlled experimental system.

Main Methods:

• Germ-free Il10-/- mice were colonized with a defined bacterial consortium (C13) or C13 plus C. jejuni.
• 16S rRNA gene sequencing was used to analyze microbial community composition.
• Spatial transcriptomics (RNAscope and FISH) provided high-resolution mapping of host gene expression.

Main Results:

• Colonization with C. jejuni in the presence of the C13 consortium induced significant intestinal inflammation and elevated inflammatory gene expression compared to C13 alone.
• Increased relative abundance of Escherichia and Paraclostridium was observed in mice infected with C. jejuni.
• Spatially resolved transcriptomics revealed localized immune responses and epithelial remodeling, with distinct host gene modulation by tissue-associated C. jejuni versus Enterobacteriaceae.

Conclusions:

• Defined microbial consortia are valuable tools for dissecting host-pathogen-microbiota interactions.
• Spatially resolved transcriptomics offers high-resolution insights into localized immune responses during enteric infections.
• Specific bacterial members within the gut microbiota can differentially modulate host responses to C. jejuni infection.