“What You Really Need to Know” Gail Lupica PhD, RN, CNE Nurs 211 The Immune System “What You Really Need to Know” Gail Lupica PhD, RN, CNE Nurs 211

Immune System Overview Non-specific Defenses (first, second) Mechanical Chemical Phagocytosis Inflammation Specific Defenses (third line of defense) The Immune response

Immune System Overview What happens? (T & B cell immunity) Antigens (complex proteins) (self or foreign) allow cells to distinguish between self and non-self. These cell markers destroy foreign antigens because they are recognized as invaders.

Immune System Overview Then next time, memory cells of the immune system recognize the same invader and a response is developed (B cell antibody). T-memory cells remember that invader, and sets off the specific ANTIGEN-ANTIBODY response

Immune System Overview Components of the Immune System Immune cells (B and T cells) Thymus (source of mat of T cells) Lymph nodes/Lymphatic tissue Adenoids, tonsils, spleen Bone marrow (source of mat of B cells)

Immune System Overview Let’s look at the Primary and Secondary Immune responses…

Immune System Antigens: Substances that elicit the immune response. All body cells have self antigens on their surface that are unique to that person . The immune system tolerates self antigens just fine, and does not recognize them as foreign. They are non-responsive to self.

Immune System Antigens: Self antigens are called cell markers That are coded by genes: Detected on cell membranes of leukocytes (Provide a close match in tissues that are to be transplanted.) EX: Human Leukocyte Antigen (HLA)

Immune System Let’s look at the cells of the Immune system…

Immune System There are two types of lymphocytes: T- Lymphoctyes (cell mediated- 70%) B- lymphocytes (humoral immunity)

Immune System Antibodies/ Immunoglobulins Produces by plasma cells in response to a challenge by an antigen Antibodies (immunoglobulins known to have specificity for a particular antigen)

Immune System Antibodies/ Immunoglobulins Are proteins with a unique sequence of amino acids on a common base Binds to a specific matching antigen and KILLS IT! They are the basis for how immunity to a disease develops. Found in general circulation. There are five classes, each with a special structure, and function:

Immune System Natural vs. Acquired Immunity (table)

Immune System Active Passive Natural Natural contact with antigen through clinical infection-- --You get the chicken pox, mumps, measles Passed through placenta to unborn infant or fed to infant through colostrum/ breast milk— (lots of IgA) Artificial Immuniza tion with an antigen--- Immunization with live or killed vaccines (tetanus) Injections or infusions of human immune globulin

Immune System What are Cytokines? Chemicals that act as messengers to cells. They can cause proliferation, differentiation, secretion or activity. There are over 100 types.

Immune System Cytokines Interleukins Colony stimulating Factor (CSF) Types: Interleukins Colony stimulating Factor (CSF) Erythropoetin (hormone) Tumor Necrosis Factor (TNF)

Immune System Hypersensitivity disorders: The immune system overreacts against foreign antigens Types: Type 1, 11, 111= humoral (immediate) Type 1V = cellular (delayed)

Hypersensitivity disorders Type 1 IgE mediated response Mast cells and Basocells release chemical mediators when an antigen (allergen) is bound to an Ig E antibody on a second exposure to this allergen. Example:???

Hypersensitivity disorders Type 11 Antibody Mediated Cytotoxic Disorders What does cytotoxic mean? Result of IgG and IgM class antibodies interacting with tissue/cell surface antigens Subsequent activation or cell-mediated cytotoxicity (the cell is doomed) occurs. Example???

Hypersensitivity disorders Type 111 Immune Complex Disorders mediated by the formation of antigen-antibody complexes (immune complexes), which cause a release of Vasoactive mediators causing tissue damage (by altering blood flow, and increasing vascular permeability.) Immune complexes produce damage both in the vascular lining itself and the organs where they may deposit (kidney, lung, joints) causing an inflammatory response. Example:???

Hypersensitivity disorders Type 1V Cell mediated “delayed” (24-72 hours) Hypersensitivity It is mediated by T-cells that are Cytotoxic and release inflammatory chemicals in the surrounding tissue. These substances attract T or B lymphocytes. The coagulation cascade is activated causing formation and deposition of fibrin. Example???

How much did you learn? Describe the development of antibodies to a specific antigen

How much did you learn? Predict why a person only has chicken pox once in a lifetime

How much did you learn? Why is a secondary response to an antigen faster and greater than the primary response

How much did you learn? Where is IgG found in the body?

How much did you learn? Explain why a newborn infant is protected from infection by the measles virus immediately after birth but later will be given measles vaccine.

Great Job!!