Advanced Course in Immunology On Demand Lecture Recordings-Innate Immunity and NK Cell Responses to Pathogens and Tumors

Video Transcription

Video Summary

The lecture gives an overview of innate immunity, focusing on natural killer (NK) cells and how they fit into the broader immune response. The speaker first emphasizes that modern immunology no longer fits neatly into rigid “innate vs. adaptive” boxes: many classic rules have exceptions, such as memory-like behavior in innate cells and self-reactivity in both innate and adaptive immunity. The immune response is also highly contextual, varying by tissue, timing, age, and infection.<br /><br />NK cells are introduced as members of the innate lymphoid cell (ILC) family. Unlike T and B cells, they do not require antigen receptor rearrangement and are especially important in early defense against viruses and tumors. They can kill target cells by releasing cytotoxic granules containing perforin and granzymes, and they also produce cytokines like interferon-gamma. Their activity can be measured by assays such as CD107 mobilization.<br /><br />A major theme is target recognition. NK cells use a balance of inhibitory and activating receptors rather than a single antigen receptor like T cells. They detect “missing self” when MHC class I is reduced, but they also require activating signals. Receptor families differ between mice and humans, reflecting convergent evolution. NK cells are further “licensed” or educated by self-MHC, which helps explain why some HLA-KIR combinations are associated with disease outcomes.<br /><br />The lecture concludes with emerging NK cell biology: memory-like NK cells, cytokine-induced memory, and NK cells as tools in cancer immunotherapy, including adoptive transfer and CAR-NK approaches.

Asset Subtitle

Lecture 2: Wayne M. Yokoyama, Washington University School of Medicine

Asset Caption

Wayne M. Yokoyama, Washington University School of Medicine - Innate Immunity and NK Cell Responses to Pathogens and Tumors

Keywords

innate immunity

natural killer cells

innate lymphoid cells

cytotoxic granules

perforin

granzymes

interferon-gamma

missing self

MHC class I

NK cell education

HLA-KIR interactions

memory-like NK cells

cancer immunotherapy