Immune System PDF Tagged Notes

Immune System Specific Immunity T-Cells (lymphocytes) Cell-to-Cell combat Cannot recognize antigens (foreign substances such as bacteria/viruses) Must the presented by APC’s (Antigen Presenting Cells) such as monocytes/macrohages  Once activated, the T-cells clone into hundred...

Immune System Specific Immunity T-Cells (lymphocytes) Cell-to-Cell combat Cannot recognize antigens (foreign substances such as bacteria/viruses) Must the presented by APC’s (Antigen Presenting Cells) such as monocytes/macrohages  Once activated, the T-cells clone into hundred of thousands of cells Cytotoxic cells which make contact with invaders and secrete cytotoxic chemicals Helper T-cells (T4 cells) that recruit the other type of lymphocytes (B-cells) into the battle. Memory T-cells – remain in the body after the initial battle, in case the subject is exposed again. This time, the immune response will be faster and more intense (this is the principle of vaccinations) Suppressor T-cells – act in a delayed way to end the immune response  B-cells can directly recognize antigens. They then can blast (change) into Plasma Cells Plasma cells can then secrete protective proteins called antibodies or immunoglobulins.  Hypersensitivity – exaggerated response to a foreign substance or a perceived foreign substance and a damage is done to the body’s own cells Type I Type III Hypersensitivities – Immune Complex Type III Hypersensitivities occur when immune complexes (Ab-Ant) have not been adequately cleared by innate immunity phagocytes and cause inflammatory reactions. Type IV Hypersensitivity Has nothing to do with Ig’s, but involves a delayed reaction with T- cells, monocytes and macrophages. Pt. must have come into contact with An at least once before. CONTACT SENSITIVITY urushiol  Chronic graft rejections PPD tests (Purified Protein Derivatives skin test such as the Mantoux Rx) Latex Nickel Poison Ivy