MIMM 214 Lecture Notes - Lecture 2: High Endothelial Venules, Innate Lymphoid Cell, Adaptive Immune System
Document Summary
Lymphocytes encounter and respond to antigen in the peripheral lymphoid organs. T cells are in the blue area (paracortical area or t-cell zone) B cells are in the beige area (follicles, at the outer cortex) Lymph nodes= have specialized blood vessels (high endothelial venules (hev)) Lymphocytes (attracted to chemokines go in the direction of the black arrow (first in paracortical area, then the follicles) Juxtaposition of antigen, antigen-presenting cells and na ve t cells= Make t-cells bind to their specific antigen (t-cell activation!) Activation of b-cells requires: antigen binding to b-cell receptor, activated t-helper cell (effector t cell) Red *: where the t and b cells meet to activate get activated (t-cell activated first, and t-helper cells move there, to help activate b-cells) No connection with lymphatic system (everything enters through blood) Collects antigen from blood and involved in immune response for blood-borne pathogens. Composed of red pulp (rbc disposal site) and white pulp (lymphoid)