Immune Flashcards
Give examples of immunosuppressant drugs:
Methotrexate, azathioprine and mercaptourine
What is the mechanism of action of immunosuppressants?
Disrupt DNA synthesis
Azathioprine: blocks purine synthesis mainly in lymphocytes
Methotrexate: stops the action of the enzyme dihydrofolate needed for production of DNA
When are immunosuppressants given?
Post transplantation immunosuppression
Inflammatory bowel disease
Renal vasculitis
Paediatric leukaemia (methotrexate is used)
What are side effects of immunosuppressants?
Bone marrow suppression (leucopenia) Risk of infection Nephrotoxicity Hepatotoxicity Seizures Gl upset Mucosal ulceration Alopecia
Give examples of anti-TNF agents:
Etanercept - receptor fusion protein
Infliximab - monoclonal antibody
Adalimumab - monoclonal antibody
What is the mechanism of action of anti-TNF agents?
Anti-TNF-a and anti-TNF-B
Blocks its interactions with TF cell receptors
TNF a and B produced from macrophages and T cells
Stimulates cytokine - IL1, IL8, IL6
Reduces inflammation
When are anti-TNF agents used?
Rheumatoid arthritis
Psoriatic arthritis
Ankylosing spondylitis
Juvenile arthritis
What are side effects of anti-TNF agents?
Injection site reactions
Flu-like symptoms (fever, headache, runny nose)
Immune deficiency - in particular risk of legionella and listeria infection and reactivation of tuberci
Give examples of orally prescribed corticosteroids:
Prednisolone
Hydrocortisone
Dexamethasone
Give examples of topically prescribed corticosteroids:
Hydrocortisone
Betamethasone
Clobetasone
Give examples of parenterally administered corticosteroids:
Methypresnisolone
Hydrocortisone
Triamcinolone
What is the mechanism of action of corticosteroids?
Bind to glucocorticoid receptors
This causes up-regulation of a variety of anti-inflammatory mediators and down regulation of pro-inflammatory mediators.
This provides immunosupression.
Glucocorticoids also have metabolic effects including increased gluconeogenesis. Some glucocorticoids also have mineralocorticoid activity (discussed below).
When are corticosteroids given?
Replacement therapy in adrenal insufficiency
Post-transplantionimmunosupression
Treatment of exacerbations of a variety of inflammatory conditions (including eczema, rheumatoid arthritis, inflammatory bowel disease and multiple sclerosis).
Treatment of acute asthma
What are side effects of corticosteroids?
Sleep disturbance Mood disturbance/ psychosis Hyperglycemia Immunodeficiency Easy bruising Moon-faced Increased abdominal fat Glaucoma Striae Hypertension Gastric irritation
What are the functions of mineralocorticoids?
Increased resorption of water
Increased resorption of sodium
Increased renal excretion of potassium
Hydrocortisone has good mineralocorticoid activity, but fludrocortisone is most potent.
