MicroPara

• immunology: study of immune system and immune response
• immunogen: any substance that are capable of inducing an immune system
• Epitope: a structure in an antigen that is recognized by B and T cells
• Hapten: a substance that is low in molecular weight that can induce an immune response if bound to another substance that is immunogenic
• antigen: a substance recognized by immune system whether by T cells or B cells, that serves as a target of the immune response but may not necessarily lead to an immune response
• 4 properties of an antigen: 1. foreignness and genetic composition 2. chemical composition and complexity 3. molecular size and shape 4. antigen's mode of entry
• foreignness and genetic composition: antigens are genetically foreign to the host or recognized by the body as non self
• most organic substances can be antigenic except for pure lipids and nucleic acids
• proteins: most immunogenic
• glycoprotein: more antigenic
• molecules with molecular weight greater than 10,000 daltons are very potent immunogens
• antigen's mode of entry: dose of antigen and mode of administration is considered
• immune system composition: 1. central lymphoid organs 2. peripheral lymphoid organds
• primary sites for differentiation and maturation of the important cells
• central lymphoid organs: 1. Bone Marrow 2. Thymus
• bone marrow: site of blood formation
• Bone Marrow: where the precursor cells differentiate into B and T cells
• B cells mature in: bone marrow
• T cells mature in: Thymus
• peripheral lymphoid organs: 1. lymph nodes 2. spleen 3. mucosa associated lymphoid tissues
• MALT: tonsils, adenoids, peyer's patches
• peripheral lymphoid organs: site of reactivity of lymphoid cells where antigens are trapped and subsequently encounter T and B cells
• peripheral lymphoid organs: where mature T and B cells are found
• Cells of the Immune system: 1. white blood cells 2. antigen presenting cells 3. other WBC 4. natural killer cells 5. T lymphocytes and B lymphocytes
• major role of neutrophils is acute inflammatio and bacterial infection
• major role of lymphocytes are chronic inflammation and viral infection
• major role of macrophages is chronic inflammation
• white blood cells consist of: 1. Granulocytes 2. Lymphocytes 3. Monocytes and Macrophages
• antigen presenting cells: cells that are involved in the processing and presentation of antigens to the T cells
• professional antigen presenting cells that are also dendritic cells and most important: Macrophages, B cells, Dendritic cells, Langerhans cells, Kupffer cells, Glial cells
• antigen presenting cells: wear MHC2 proteins
• follicular dendritic cells are found in lymphoid follicles
• dendritic cells: considered as true link between innate and adaptive immunity
• langerhans cells: skin
• kupffer cells: liver
• glial cells: CNS
• langerhans cells: bring antigens to paracortical zone of lymph node
• Other WBC include: eosinophils, basophils, platelets
• eosinophils: secrete major basic protein that is toxic to parasites
• eosinophils: possess eosinophilic granules that play a role in type I hypersensitivity reaction or allergies