What does the immune system do? X3
- Detect self from non-self: meaning: autoimmune: what us suppose to be there versus not? Attacks stuff that is not suppose to be there
- Nonspecific response: inflammation
- Specific response: recognize and remove undesirable material from cells, tissue, and organs (what exactly is it targeting? I know what that is and I am going to attack it)
What does the thymus mature T cells do?
Active in fetal development to ignore self antigens later on the thymus becomes less active
What is an antigen?
Either foreign substances or human cell surface molecules that are unique in each individual
1. Activate the immune system to produce specific antibodies
2. Major histocompatibility complex: MHC: inherited from parents, codes for antigens representing self that are displayed in cellular plasma membranes
What does an autoimmune disease do?
Diseases are an exception n which the immune system no longer recognizes self from no self and begins to attach its own cells/ structures or organisms
What does a macrophage do?
Large phagocytes cell that intercept and engulf foreign material (pac man cell)
Then process and display antigens from the foreign material on their cell membrane
Lymphocytes respond to this display by initiating the immune response
What does a lymphocyte do?
- Primary cell in the immune response
- B lymphocytes: humoral immunity and T lymphocytes: cell mediated immunity
- Natural killer cells are lymphocytes distinct from t and b lymphocytes: they destroy without any prior exposure and sensitization,tumor cells and cells infected with viruses
What do T Cells do?
Cell mediated immunity develops when a T lymphocyte with protein receptors on the cell surface recognizes antigens on the surface of target cells and directly destroys the invading antigens
- Cytotoxic CD8 positive killer cells: regulate all cells in the immune system- who needs to go where
- Helper CD4 positive T cells- facilitate the immune system response by secreting messenger cytokines: HIV VS. AIDS
- Memory T cells: remain in the lymph nodes for years, ready to activate the response again if the same invader returns
What does B cells do?
Human immunity though the production of antibodies (immunoglobulins)
B lymphocytes act primarily against bacteria and viruses that are outside the body cells
1. Becomes antibody producing plasma cells or a b memory cell
2. B memory cells provide for repeated production of antibodies
3. Antibodies bind to the specific matching antigen and destroy it (lock and key)
Made and matured in the bone marrow
IgG location and action
Location: Most common antibody in the blood
Action: Antibacterial, antiviral, and antitoxin antibodies: Crosses placenta creating passive immunity in newborns
IgM location and action
Location: Bounded to B lymphocytes in circulation, Usually the first to increase in the immune response
Action: Forms natural antibodies: involved in blood ABO types incompatibility reaction
IgA location and action
Location: Secretions such as tears and saliva, in mucous membranes, and colostrum
Action: Protects newborns: immune function of mucus membranes
IgE location and action
Location: Binds to Mast cells in skin and mucous membranes , eosinophils
Action: When linked to allergens, cause release of histamine and other chemicals, resulting in inflammation
IgD location and Action
Location: Attached to B cells
Action: Activates B cells
What is the immune response like after the first introduction?
Rapid and intense
What is HLA (MHC) Typing?
Complete tissue matching before transplant procedures
What is active immunity?
Develops in a persons own body develops antibodies or T cells in a response to a specific antigen introduction into the body
Previous infection, long lasting
What is passive immunity?
Antibodies are transferred from one person to another: think mother to baby or transfusions
Example Mechanism Memory of Natural Active
Person has an infection then develops antibodies
Yes
Person has chicken pox once
Example Mechanism Memory of Artificial active
Vaccine is infective into a person; no illness results, but antibodies from it
Yes
Measles vaccine
Example Mechanism Memory of Natural Passive
Antibodies passed directly from mother to baby to provide temporary protection
No
Breast milk
Example Mechanism Memory of Artificial Passive
Antibodies injected into person to provide temporary protection or minimize severity of infection
No
Gamma globulin if recent exposure to microbe: transfusions
Obstacle
Immune system of recipient responds to HLAs in foreign tissue rejecting and destroying graft tissue
Example, Mechanism, Effects of TYPE 1 Allergic reaction
Hay fever, anaphylaxis, asthma, eczema, food allergies
IgE bonds to mast cells; release of histamines and chemical mediators
Immediate inflammation and pruitus
Example, Mechanism, Effects of TYPE 2 Cytotoxic Hyper- sensitivity
IgG or IgM reacts with antigen on cell complement activated
IgG or IgM reacts with antigen on cell complement activated
Cell lysis and phagocytosis
