Changes in Gut Microbiota Prior to Influenza A Virus Infection Do Not Affect Immune Responses in Pups or Juvenile...

Area of Science:

• Microbiology
• Immunology
• Virology

Background:

• Previous research linked antibiotic (ABX) use during influenza A virus (IAV) infection in adult mice to altered gut microbiota (GM) and increased susceptibility.
• The impact of early-life ABX exposure on GM development and subsequent antiviral immunity remains less understood.

Purpose of the Study:

• To investigate the effects of perinatal and juvenile antibiotic treatment on gut microbiota composition.
• To determine if early-life antibiotic cessation influences susceptibility and immunity to influenza A virus infection.
• To assess the lasting impact on adaptive cellular and humoral antiviral immunity.

Main Methods:

• Antibiotic treatment was administered to neonatal mice (perinatal) and juvenile mice.
• Mice dams also received antibiotic treatment.
• Susceptibility to IAV, GM composition, and adaptive immune responses were analyzed following infection after antibiotic cessation.

Main Results:

• Antibiotic treatment significantly altered gut microbiota composition in juvenile mice and dams.
• However, mice whose antibiotic treatment ceased before IAV infection showed no increased susceptibility.
• No major differences in cellular and humoral adaptive antiviral immunity were detected in neonates or juveniles post-cessation.

Conclusions:

• While early-life antibiotic exposure alters gut microbiota, its cessation allows for effective immune recovery.
• Re-colonization of the gut microbiota following antibiotic cessation correlates with robust immunity against influenza A virus.
• These findings highlight the resilience of the immune system and gut microbiota following transient early-life antibiotic exposure.