PSL201Y1 Lecture Notes - Lecture 25: T Helper Cell, Cytotoxic T Cell, Natural Killer Cell
Document Summary
Helper t cells among the important lymphokines secreted by the helper t ells are following. Il2, il3, il4, il5, il6, granulocyte-monocyte colony stimulating factor interferon gamma. Certain cancers and viruses, they actively inhibit production of class 1 mhc on affected cells so enable these to escape detection by cytotoxic t cells. Suppressor t cells regulate activities of the other cell and prevent excessive immune reactions that may be damaging to body"s own tissue play a role in immune tolerance. Cytotoxic t cell is activated either by specific contact with infected cell presenting viral antigens by class 1 mhc and il-2 secreted by helper t cell these then produce perforins and fragmentins and induce cell death. Immune dysfunctions allergy autoimmune diseases immunodeficiency diseases role of stress in the immune response. Which can result from histamine induced contraction of smooth muscle in respiratory airways.
