IMMUNOLOGY2024™ Conference Recordings-Tissue and age determinants for human immune response

Video Transcription

Video Summary

The speaker described a large human tissue resource from organ donors spanning infancy to old age, allowing study of immune cells across many organs and ages. The focus was on how tissue location and age shape immune responses, especially T cells and gamma-delta T cells.<br /><br />Key findings:<br />- Immune cell composition is highly tissue-specific. Blood and lymph nodes contain mostly naive cells, while gut and lung are enriched for tissue-resident memory T cells (TRM), which are important for protection.<br />- TRM have a shared core gene program across tissues, including markers that help them stay in place and rapidly respond, but they also show tissue-specific adaptations. For example, gut TRM differ from lung and skin TRM transcriptionally and clonally.<br />- Adult tissues show stable T-cell composition, but age can reduce some functional features, such as lymphoid identity or cytokine production.<br />- Gamma-delta T cells change much more dramatically with age. Children have more diverse, tissue-repair-oriented gamma-delta cells, while adults have more clonal, effector-like, cytolytic cells.<br />- These age-related differences may help explain why children are often protected from severe tissue damage during infections.<br /><br />The talk ended with discussion of plasma cells, memory formation, sex differences, and how tissue environment and inflammation influence TRM development.

Keywords

tissue-resident memory T cells

TRM

gamma-delta T cells

immune cell composition

tissue specificity

age-related immune changes

organ donor tissue atlas