What do T-cells attack?
Foreign cells, malignant cells, and cells infected with microorganisms.
Where do T-cells undergo maturation?
What are examples of type I, II, III, and hypersensitivity?
- 1. Type I- Includes allergic reactions (hives, hay fever, asthma)
- 2. Type II- Generally cytolytic or cytotoxic reaction that destroys host cells. (Blood type, Rh factor)
- 3. Type III- Involves formation of immune complexes, can cause inflammation and damage to blood vessels. (arthritis, glomerulonephritis, systemic lupus)
What are normally the sterile environments of organs in humans?
Kidneys, ureters, and urinary bladder and the upper and lower respiratory tracts.
How do tears protect the eyes?
Tears (lacrimal fluid) contain large amounts of lysozyme, lactoferrin and sIgA, and they provide chemical and physical protection.
What does humoral immune response defend against?
The circulating antibodies bind to microorganisms, toxins, and extracellular viruses neutralizing them or “tagging or marking” them for destruction.
What class(es) of protein(s) is/are directed by MHC?
Transmembrane proteins in the plasma membrane. They are also called HLA (human leukocyte antigen) in humans.
What are the functions and characteristic of mast cells?
Bone marrow derived cells that differentiate themselves in the blood and connective tissue. They contain granules with histamine and other chemicals that contribute to immune/inflammatory response
How does the host have acquired immunity?
By being exposed to a foreign substance or antigens or after transfer of antibodies or lymphocytes from an immune donor. Acquired immunity may be obtained actively or passively by natural or artificial means.
How antibodies are induced to be produces?
Where are they produced?
Made by plasma cells
What are signs of true food allergy?
Itching, vomiting, nausea, diarrhea.
What is an example of atopic allergy of the lower respiratory tract?
What immunoglobulin crosses the placental barrier?
Transfer to infant during breast feeding?
What happens in the lag phase, log phase, plateau phase, and decline phase of immune response? (primary)
- Primary antibody Response
- 1. Lag phase- last several days
- 2. Log phase- antibodies titer rises logarithmically
- 3. Plateau phase- antibodies titer stabilizesDecline phase- antibody titer decreases because the antibodies are metabolized or cleared from the circulation
What happens in the lag phase, log phase, plateau phase, and decline phase of immune response? (secondary)
- Secondary Antibody Response
- 1. Lag phase- much shorter
- 2. Log phase- more rapid, longer plateau, attains higher IgG titer, produces antibodies with higher affinity for antigen
Why is the secondary immune response stronger than the primary immune response?
Because the primary response is not 100% effective
What are the characteristics associated with secondary antibody response?
Has a shorter lag phase and a more rapid log phase, persists for a longer plateau period, attains a higher IgG titer, and produces antibodies with a higher affinity for the antigen.
What type of antigens does the immune system discriminate?
What does the immune system discriminates between?
self and non-self
what role do myeloma cells play in a special type of anti-body production?
productes large quantities of antibodies used for detection.
What are the characteristics and/or function of IgG
- IgG-major Immunoglobulin in human serum;accounts for 80% of the immunoglobulin pool.
- i. Antibacterial & antiviral
- ii. Enhances oponization; neutralizes toxins
- iii. Only IgG is able to cross placenta (naturally acquired passive immunity for newborn)
- iv. Activates the complement system by classical pathway
What are the characteristics and/or function of IgD
- IgD-monomeric protein; trace amounts in serum
- i. Does not activate the complement system and cannot cross placenta
- ii. Abundant on surface of b cells where it plays a role in signaling B cells to start antibody production.
What are the characteristics and/or function of IgM
- IgM- pentameric protein joined with J chain at F ends; 10% of Ig pool.
- i. First antibody made during B-cell maturation and first antibody secreted during primary antibody response
- ii. Never leaves the bloodstream
- iii. Agulates bacteriaand activates compement by classical pathways; enhances phangocytosis of target cells
- iv. Up to 5% may be hexameric; hexameric form is better able to activate the complement system than pentameric IgM; bacterial cell wall antigens may directly stimulate b cells to produce hexameric form.
What are the characteristics and/or function of IgA
- IgA- 15% of Ig pool
- i. Some monomeric forms in serum, but most is dimeric (using a J chain) and associates with protein called the secretory component (secretory IgA or sIgA)
- ii. sIgA is primary Ig of mucosal-associated lymphoid tissue;also found in saliva. Tears and breast milk (protects nursing newborns); help rid the body of antigen-antibody complexes by excretion; functions in alternate complement pathway.
What are the characteristics and/or function of IgE
- IgE- makes up small % of Ig pool
- i. Classic skin sensitizing and anaphylactic antibodies belong to this class
- ii. Fe portion of IgE can bind to special Fe receptors on mast cells, eosinophils, and basophilsDegranulation releases histamine and other pharmacological mediators of inflammation.