immunology

Question 1

Myasthenia gravis

Answer 1

Myasthenia gravis is an autoimmune disease which results from antibodies that block acetylcholine receptors at the junction between the nerve and muscle. This prevents nerve impulses from triggering muscle contractions.

Question 2

Graves disease

Answer 2

is a autoimmune disease that come from antibodies connecting to the TSH receptor in the thyriod gland and increase the production of T3 and T4. resulting in hyperthyroidism

Question 3

Haemolytic desease of a newborn

Answer 3

IgG molecules produced by the mother pass through the placenta.

Among these antibodies are some which attack antigens on the red blood cells in the fetal circulation, breaking down and destroying the cells (haemolysis). The fetus can develop reticulocytosis and anaemia.

Question 4

The ABCD of immune reactions

Answer 4

A= Allergy
B=AntiBody - antigen reaction
C=Immune Complexes
D= Delayed hypersensitivity

Question 5

how many types of hypersensitivity and give an example of one disease in each.

Answer 5

4 types

type I= immediate hypersensitivity

• basically an antibody-antigen reaction
• IgE attaced to mast cells
  ex: asthma, hayfever

type II= self-cell lysis

• basically antibodies targeted aganst cells
• If the target antigen is on a cell surface, the antibody would be expected to disrupt cell function, and would probably kill the cell.
  ex: graves disease, Myathenia gravis

type III= hypersensitivity occurs when there is accumulation of immune complexes (antigen-antibody complexes) that have not been adequately cleared by immune cells, giving rise to an inflammatory response and attraction of leukocytes. Such reactions progressing to the point of disease produce immune complex diseases.

• Symptoms include fever, joint pain, dermatitis, lymphadenopathy, and in severe cases proteinuria and compromised pulmonary function. Similar symptoms occur in SLE.
  ex: Polyarteritis nodosa, SLE, and advanced cancers

type IV: Delayed-type hypersensitivity
-Contact dermatitis is the most common and probably most pure form of delayed hypersensitivity
-It is usually due to organic compounds or heavy metals such an nickel attaching to proteins in the skin and acting as haptens.
-The combination is then taken up, by tissue Langerhans’ cells, processed, and expressed on the cell surface in association with class II MHC proteins.
-Antiself T cells (TDh)cells are activated
ex: autoimmune myocarditis, diabetes type 1, hashimoto`s thyroiditis
MS

Question 6

What Is goodpasture syndrome

Answer 6

An autoimmune disease in which antibodies attack the basement membrane in lungs and kidneys, leading to bleeding from the lungs and kidney failure. It is thought to attack type IV collagen, which has therefore been referred to as Goodpasture antigen.