Immune System Function PDF

The Immune System Complex defense mechanism that protects from injurious agents Can decip...

The Immune System Complex defense mechanism that protects from injurious agents Can decipher which substances are “self” vs. “non-self” Immune System Function Non-self = antigens In a normally functioning immune system Rapid identification of an antigen and subjects it to barriers and protective cellular forces that destroy the threat Professor Shermel Edwards-Maddox, PhD, RN, RN-BC 0 Innate vs. Adaptive Immunity Adaptive Immunity Goals: recognize self from non-self (antigen) recognize and target a specific antigen Innate Adaptive limit its response 1st line of defense Occurs after innate development memory for future exposures (specificity) Natural mechanism More specific Barriers defense Memory response allows for quicker response upon 2 nd Normal flora Exposure to exposure WBC’s antigen Enzymes Use memory for Driven by lymphocytes that originate in bone marrow in Chemicals specific antigens immature form cannot initiate immunity until mature. 2 Types of Adaptive Immunity Humoral Cell-mediated  2 Categories of Adaptive Immunity Humoral- B Cell Immunity Immunity is developed by B lymphocytes producing Humoral Immunity Cell Mediated Immunity antibodies Known as B cell immunity Known as T cell immunity They are naïve or immature until they encounter antigens. Mature in the bone marrow, spleen, and Mature in the thymus gland  found in lymph nodes bloodstream and lymph nodes After exposure to an antigen, B cells mature into plasma Protects against extracellular pathogens Protects against intracellular pathogens cells. Plasma cells have the ability to produce specific proteins called immunoglobulins (Igs), also called antibodies. Ex: IgG, IgA, IgE, IgM, IgD Specifically recognize and bind to particular antigens Support is provided by helper T cells to help promote/escalation of immune response Cell Mediated Immunity Cell Mediated- T Cell Immunity Adaptive Immunity: Passive or Active Immune response without the use of antibodies Active Acquired Passive Acquired Uses macrophages, T-lymphocytes, and cytotoxic cells Obtained through exposure to an Premanufactured immunoglobulins are for a direct approach at pathogen destruction antigen or through immunization given or passed down. Antigen provokes antigen presenting cell (APC) which (vaccine). The body passively accepts processes antigen The patient’s body has to synthesize immunoglobulins and the body DOES specific immunoglobulins against an NOT have to manufacture them. Stimulates T-helper cells and activates macrophages antigen. This is short-term immunity. Antigen fragments are put on the surface of the APC, Either the patient contracts a disease Administered when the patient needs triggering CD8 cells known as cytotoxic cells IMMUNITY NOW because of being with and develops Igs and then recovers or CD8 cells destroy cell via apoptosis the patient is given a vaccine. close contacts or a family member who has the virus. Both endow long-term immunity. Example: hepatitis B immunoglobulin (Hbig) and immunoglobulins in breast milk Immunizations and Boosters Antibody Titer A vaccine is a weakened or inactivated virus Antibody screening tests, referred to as antibody titers, confirm adequate immune protection It cannot cause disease; it has the genes for disease removed. by measuring IgM and IgG immunoglobulins. A vaccine is administered to the body and the body “thinks” it is an antigen. If a patient has a negative titer: The body then builds specific Igs against it. They have not been exposed to disease Sometimes more than one dose is needed. Never developed immunity Example: hepatitis B vaccine (three doses) Need vaccination/booster Booster: This is a repeated vaccine administered some time after the initial vaccine in order to “remind” the body to make immunoglobulins. Examples: MMR booster is recommended before college Tdap every 10 years Influenza vaccine COVID-19 Copyright © 2016 F.A. Davis Company