Unit 2 Flashcards
Triggers the production of B lymphocytes, leading to destruction of the invader
Antigens
Type of immunity mediated by B-cell activation
Humoral immunity
Type of immunity mediated by T-cells, responsible for defense against intracellular microbes
Cell-mediated immunity
Low-molecular weight molecules that may contain antigenic determinants but may not be able to stimulate an immune response
Haptens
These molecules enable lymphocytes to responds to a limitless number of antigens but also recognize and ignore self-antigens expressed on tissues
Major Histocompatability Complex Molecules (MHC)
Most abundant Ig
o Possess antiviral, antibacterial and antitoxin properties
o Present in all body fluids, enters all tissues and is capable of crossing the placenta (passive immunity)
o 4 subclasses with specificity for certain types of antigens
IgG- gamma globulin
Second most abundant Ig- two identical molecules- second most common
o Secretory- found in saliva, tears, colostrum and bronchial, GI, prostatic and vaginal secretion
o Major function is local immunity on mucosal surfaces- prevents attachment of viruses and bacteria to epithelial cells
- acts locally rather than systemically
IgA
Ig- 5-membered macromolecule with identical heavy and light chains
o Agglutinating antibody- stimulating clumping of organisms for eventual lysis and elimination
o First antibody to be produced by the developing fetus and by immature B lymphocytes
- first to appear in response to an antigen
- effective in gram negative infection
-bound to B lymphs
-activates complement
IgM
Ig found on cell membranes of B cells
o Functions as a receptor for antigen
o Circulates in the serum in extremely low levels where its function is essentially unknown but may play a role in B-cell differentiation
- found primarily on cell membranes of B lymphs
IgD
Ig- least common serum IgE because it binds tightly to Fc receptors on basophils and mast cells
o Involved inflammation and allergic responses by causing mast cell degranulation and release of chemical mediators including histamine
o Essential for combating parasitic infections
IgE
The central event in initiation of humoral and cell-mediated immune responses
Activation of helper T Cells
- Function to control immune system responses
Regulatory T Cells
- CD 8- monitor the activity of all cells in the body and destroy any that threatens the integrity of the body
Cytotoxic T Cells
Central organs for immune system
Bone marrow and thymus
Responsible for T cell maturation
Thymus
Classic allergic response
Type I- IgE mediated hypersensitivity d/o
Release of histamine is associated with which cells
Mast cells and basophils
A prostaglandin released from platelets that plays a role in platelet aggregation
Thromboxane (TXA2)
This clotting factor is produced in the endothelial cells of blood vessels and circulates in the blood as a carrier protein for coagulation factor VIII- required for platelet adhesion
von Willebrand factor
Most platelet defects result in ______
Bleeding
Cyclooxygenase-1 (COX-1) inhibitors prevent clot formation by inhibiting prostaglandin synthesis, including TXA2- what is an example of this?
Aspirin
In liver damage, bleeding is more likely to occur because of lack of _______ synthesis
Prothrombin
Clotting pathway- Slow process, begins in circulation with activation of factor XII
Intrinsic
Clotting pathway-must faster (can cause clotting in 15 seconds)- begins with trauma to the blood vessel or surrounding tissues and release of tissue factor or tissue thromboplastin
Extrinsic
Both pathways terminate at the same step-activation of factor ___, which helps convert _____ to ______
X, prothrombin to thrombin
Proenzyme for fibrinolytic process is converted to its active form, plasmin- also, what’s the drug we use???
Plasminogen, tissue plasminogen activators (TPA!)
Causes activated Protein C Resistance (clotting d/o)
Factor V Leiden
Activates other lymphocytes and phagocytes
Helper T cells
Keeps cells in check to that an exaggerated immune response does not occur
Regulatory T cells
Activation of t-lymphocytes (t-helper and t-cycotoxic)- responsible for body’s defense against intracellular microbes like viruses
Cell-mediated Immunity
B-lymphocyte activation and antibody production
Humoral Immunity
Mature in bone marrow and secrete antibodies
B cells
Derived from the stem cell
Lymphocytes
Type of cell for humoral immunity
B cells
Type of cell for cell-mediated immunity
T cells
Also known as gamma globulins or immunoglobulins
Antibodies
The activated B cell divides and undergoes maturation into a ______, which produces thousands of antibodies and releases them into the blood and lymph to bind to and remove their antigen
Plasma cells
Orchestrate and control immune response/ direct the action of the immune response
Regulatory cells (t helper, t suppressor, and antigen presenting cells)
Cells that are able to attack the antigen and destroy it
Effector cells (t cytotoxic, B cells to produce antibodies, and leukocytes)
Immune response- when body first encounters the antigen- slower response, B cells need to proliferate and differentiate into plasma cells to produce the antibody
Primary Immune response
Immune response- memory cells are available, rise in antibody is more rapid because memory cells don’t have to differentiate
Secondary Immune response
Hypersensitivity Reaction:IgE mediated
o Against environmental antigens (allergens)
o IgE binds to receptors on surface of mast cells
o Histamine release causing itching, urticaria, conjunctivitis, rhinitis, hypotension, bronchospasm, dysrhythmias, GI cramps and malabsorption
o First, sensitizing event or exposure causes no symptoms, second event causes rapid reaction (immediate- within minutes)
o Can be inherited, called atopic
I