Short duration- lasts weeks or months Naturally occurring- maternal antibodies transfer to a fetus across placental barrier and through breast milk Artificial- antibodies from sensitized host (e.g. animal) to a non-immune recipient (antiserum) Hypersensitivity vs. Immunological Tolerance Immunological Tolerance The body does not generate immune or inflammatory reactions to any of the bodies own tissues or to outside substances Hypersensitivity There is an exaggerated or inappropriate response to body tissues or outside agents which act as antigens Altered immunologic response to an antigen that results in disease or damage to the host In hypersensitivity, the body is abnormally identifying substances as antigens which it should normally immunologically tolerate. This abnormal, immunologically generated inflammatory reaction, can lead to damage of body tissues. Clinically hypersensitivity gives rise to two categories. Allergies Autoimmune disease Allergy Deleterious effects of hypersensitivity to environmental (exogenous) antigens There is an exaggerated inflammatory response to an environmental agent An antigen that generates an allergic reaction is called an allergen Antibodies Antibodies are immune proteins which are specifically synthesized to combat a specific antigen Antibodies are made of protein molecules called immunoglobulins IgA, IgD, IgE, IgE, IgM In an allergy, there is an abnormal antigen-antibody reaction which means the antibodies must be already present in body for the reaction to occur. IE the patient must have had a previous exposure – Alloimmunity Immune reaction to tissues of another individual Alloimmunity is the development of reactions to antigens produced by members of the same species. The body recognizes them as foreign and attacks them, just like it would if it was exposed to antigens from other organisms. (Friendly fire) Alloimmmunity can occur
Short duration- lasts weeks or months Naturally occurring- maternal antibodies transfer to a fetus across placental barrier and through breast milk Artificial- antibodies from sensitized host (e.g. animal) to a non-immune recipient (antiserum) Hypersensitivity vs. Immunological Tolerance Immunological Tolerance The body does not generate immune or inflammatory reactions to any of the bodies own tissues or to outside substances Hypersensitivity There is an exaggerated or inappropriate response to body tissues or outside agents which act as antigens Altered immunologic response to an antigen that results in disease or damage to the host In hypersensitivity, the body is abnormally identifying substances as antigens which it should normally immunologically tolerate. This abnormal, immunologically generated inflammatory reaction, can lead to damage of body tissues. Clinically hypersensitivity gives rise to two categories. Allergies Autoimmune disease Allergy Deleterious effects of hypersensitivity to environmental (exogenous) antigens There is an exaggerated inflammatory response to an environmental agent An antigen that generates an allergic reaction is called an allergen Antibodies Antibodies are immune proteins which are specifically synthesized to combat a specific antigen Antibodies are made of protein molecules called immunoglobulins IgA, IgD, IgE, IgE, IgM In an allergy, there is an abnormal antigen-antibody reaction which means the antibodies must be already present in body for the reaction to occur. IE – the patient must have had a previous exposure Alloimmunity Immune reaction to tissues of another individual Alloimmunity is the development of reactions to antigens produced by members of the same species. The body recognizes them as foreign and attacks them, just like it would if it was exposed to antigens from other organisms. (Friendly fire) Alloimmmunity can occur
5._diseases_of_immunity.docx