Gut Microbiota Co-microevolution with Selection for Host Humoral Immunity

Area of Science:

• Immunology
• Microbiology
• Animal Science

Background:

• The gut microbiota and host immune system engage in complex interactions.
• Understanding host-microbiota coevolution is crucial for host health and disease.
• Chickens offer a valuable model for studying host-microbiota-immunity dynamics.

Purpose of the Study:

• To investigate the coevolutionary relationship between the gut microbiota and host humoral immunity.
• To determine how microevolution of host immunity influences gut microbial composition and function.
• To identify specific microbial taxa and pathways involved in host-microbiota co-adaptation.

Main Methods:

• Utilized chicken lines divergently selected for antibody titers (HAS, LAS) and their relaxed sublines (HAR, LAR).
• Analyzed gut microbiota composition and function using high-throughput sequencing and bioinformatics.
• Correlated changes in host immune traits with microbial community structure and functional pathways.

Main Results:

• Host immune microevolution significantly shaped gut microbiota composition at the taxa level.
• Relaxing immune selection led to the enrichment of specific microorganisms.
• Enriched Ruminococcaceae and *Oscillospira* in HAR lines reduced antibody response, while *Lactobacillus* in LAR lines enhanced it.
• Microbial functional pathways related to the immune system and infectious diseases were altered.

Conclusions:

• Demonstrated a co-microevolutionary relationship between host immunity and the gut microbiota in chickens.
• Gut microorganisms play a significant role in modulating host immune responses.
• Findings highlight the reciprocal influence between host genetics, immunity, and the gut microbiome.