IMMUNOLOGY2026™ Conference Recordings For Attendees-Maternal regulation of offspring immunity

Video Transcription

Video Summary

The talk explored how maternal antibodies, especially IgG in breast milk, shape immune development in early life. The speaker’s lab studies how newborns learn to tolerate beneficial microbes and food antigens while still responding to pathogens. Using mice that lacked maternal antibodies, they found that infants without these antibodies developed exaggerated gut immune activation after weaning, including expansion of T follicular helper (TFH) cells and germinal center B cells in gut-associated lymphoid tissues.<br /><br />They then showed that this effect depends on antibodies received in the first week of life. Purified milk IgG, but not IgA, was sufficient to suppress the abnormal TFH response. This IgG had to be consumed orally, bind intestinal microbes, and signal through the offspring’s Fc receptor and complement pathways. It did not significantly alter overall microbiota composition, suggesting it works by immune programming rather than by reshaping the microbial community.<br /><br />The speaker also showed that maternal IgG influenced responses to a new dietary antigen (ovalbumin), reducing TFH and IgE responses while promoting tolerance-associated T cell states. The proposed model is that maternal IgG provides early, local instructional signals that help the infant immune system develop tolerance to unpredictable environmental antigens, while pathogen-specific antibodies can still protect against infection.

Meta Tag

Date April 16, 2026 10:09 AM - 10:42 AM

Room 253

Session Major Symposium A: Early Life Immune Development and Function

Speaker Meghan Koch

Track Hematopoiesis and Immune System Development (HEM)

Year 2026

Keywords

maternal antibodies

IgG

breast milk

immune development

T follicular helper cells

gut immune tolerance

microbiota

April 16, 2026 10:09 AM - 10:42 AM

253

Major Symposium A: Early Life Immune Development and Function

Meghan Koch

Hematopoiesis and Immune System Development (HEM)

2026