LIFESCI 2 Lecture 5: The Immune System LS 2.docx
Document Summary
Physical barriers (non specific: skin(keratin, mucous membranes, cornea(fibrous layers of eyes) Makes hematopoetic stem cells which differentiate into different types of immune cells. Release cytokines(trigger immune response and signal) and vasodilators and chemotaxins(attract immune cells to location) Monocytes(in circulating blood)/ macrophages(in tissue and going to attack): engulf and digest, activate t cells. Mast cells: found in connective tissues (not blood), release histamine(dilate) and other chemicals involved in inflammation. B lymphocytes: transform into plasma cells and release antibodies into circulation, form memory cells. Cytotoxic t cells induce apoptosis; release perforin and granzymes. Lymph nodes: round structures dispersed at lymphatic vessels; filled with lymphocytes which kill pathogens in lymph. Nonspecific immune response/ inflammatory response: phagocytosis and recruitment, macrophages detect bacteria and engulf them, macrophages release cytokines, mast cells release histamine d. Injured cells release chemotaxins: histamine causes vasodilation, edema(inflammation) and increase in permeability a.
