Immunotoxicology Flashcards
What is immunotoxicology?
The study of undesired effects resulting from the interactions of xenobiotics with the immune system
What are NSAIDs?
Inhibitors of cyclooxygenase (COX, enzymes that make prostaglandins)
E.g. ibuprofen, aspirin, or coxibs (COX2 selective)
Blocks hydrolysis of arachidonic acid, which prevents production of peroxidase
What is methotrexate?
Acts against rapidly dividing cells, used as cancer chemotherapy drug
Bone marrow/immune system also have rapidly dividing cells, therefore methotrexate is an immunosuppressant
used for cases of rheumatoid arthritis where all other drugs have failed
What is carbimazole?
Treatment for hyperthyroidism/Grave’s disease, inhibits thyroid hormone production
Grave’s disease is an autoimmune disease that is the most common cause of hyperthyroidism
Decreases the uptake of inorganic iodine by the thyroid
A pro-drug for methimazole
Toxic to bone marrow
Allergy as an overreaction of the immune system
Allergens are linked to specific IgE antibodies. IgE are also associated with some viral and parasitic infections, immunodeficiencies, and asthma.
Sensitisation - Dendritic cells capture the allergen antigen and present it to T cells. Th2 T cells then secrete interleukins resulting in B cells producing IgE. IgE binds to mast cells.
Exposure after initial sensitisation to the allergen leads to the immediate production of a large quantity of associated IgE antibodies from B cells. The allergens bind to the IgE on mast cells, causing mast cell degranulation
Autoimmune disease as an overreaction of the immune system
An autoimmune disease is a condition in which the immune system mistakes healthy body cells as foreign. Autoantibodies are released damaging these healthy body cells.
Examples include rheumatoid arthritis, multiple sclerosis or Crohn’s disease (IBS).
What is a mast cell? What does activation of mast cells do?
Mast cells are present in all connective tissue, especially at mucosal surfaces of the gut and lungs, in the skin and around blood vessels. They contain many granules of histamine and other inflammatory mediators which are released when the cells are activated. Inflammatory mediators increase blood flow to the infected or damaged areas, recruit immune cells, induce fever and promote pain.
What are the symptoms of anaphylaxis?
Swelling of face, lips, tongue and around eyes
Itching of inner ear, nose, mouth and back of throat
Hives, flushing
Signs of low blood pressure, light headed, faint, clammy, confused
Hoarse voice, difficulty swallowing
Wheeze cough and nosing breathing
Abdominal pain, nausea, vomiting, diarrhoea
