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Immunity. It is the ability of the body to protect itself against foreign agents [I] Natural [II] Acquired immunity immunity. These are foreign agents protein or glycoprotein which produce an immune response e.g bacteria, viruses and foreign cells.
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Immunity • It is the ability of the body to protect itself against foreign agents • [I] Natural [II] Acquired • immunity immunity
These are foreign agents protein or glycoprotein • which produce an immune response • e.g bacteria, viruses and foreign cells. • Antigen • Haptens These are substances with low molecular weight (<8000) as drugs(pencillin) which combine with a protein in the body and then behaves as a foreign protein and initiates immune response.
[I] Natural immunity (1) Intact skin. - Engulfing of foreign particles (2) phagocytes - Destruction and digestion of engulfed organisms (3) The presence of certain chemical structures as Lysozymes • 3-Natural Killer Cells • 4-Inflammation • 5-COMPLEMENT • 6-INTERFERONS
[II] Acquired immunity • It is of two types 1-Humoral immunity 2-Cell-mediated immunity:
Memory T-cells (Thymus) Cellular immunity T-lymphocytes Cytotoxic T-cell (T8) Stim. (+) Inh. (-) Helper T-cell (T4) Supressor T-cell Bone marrow lymphocytes precursors Stimulation (+) Inhibition (-) Humoral immunity Plasma cells B-lymphocytes (liver-spleen) Memory B-cells Cell mediated immunity IG’s M,A,G,E,D
The memory T & B cells persist in the body for years and readily converted to effector cells by exposure to the same antigen giving more rapid and greater immune response as in vaccination. Secondary immune response
NK and LAK cells K cell Activated macrophages Eosinophils Non-specific Killer Cells
also known as large granular lymphocytes (LGL) kill infected and malignant cells activated by IL2 and IFN-to become LAK cells Natural Killer (NK) cells
kills malignant cells kills transformed and malignant cells Lymphokine Activated Killer (LAK) cell IFN IFN IL2 IL2
K Cells • morphologically undefined • have IgG Fc receptor • recognize antibody coated targets • could be NK cells (IgG), macrophages (IgG), eosinophils (IgE) or other cells (IgG)