Immunology - 20 Flashcards
Is a carrier different from an adjuvant?
- Haptens are not immunogenic. They have to be bound to a carrier to elicit an immune response.
- Antigens that are mixed with adjuvants are themselves immunogenic. Adjuvants do not form stable linkages with the antigen they are mixed with
Which drugs are the most common real-life examples of haptenation: drug-induced immune hemolytic anemia?
- Methyldopa
- IV penicillin
The drug haptenates red blood cells causing phagocytosis of RBC because it has been marked as foreign (causes anemia)
Why do drugs tend not to be immunogenic?
Size matters. Small molecular structures do not elicit much of an immune response. Must be greater than 10,000 Da for proteins and 100,000 for polysaccharides. Because larger molecules are less soluble (less likely to be broken down), and the more visible to antibodies so they are easier for APC’s to phagocytose
Are molecules with lots of side chains good or bad immunogens?
Good
Are immunogens charged or neutral, hydrophilic or hydrophobic?
Charged, hydrophilic
Why are prosthetic devices not immunogenic?
Big, not a simple structure, not self, can’t be degraded so they can’t be presented to T cells
Is density important for immunogens?
Yes, the more epitopes, the more antibodies combined, the more complement is activated, and the more opsonization there is.
Also the more foreign, the better
Which routes of administration elicit a stronger immunogenic response,
Subcutaneous or intramuscular elicits a stronger response than oral
Which immunoglobulin subtype is only present when the baby is breast-fed?
IgA
What are epitopes?
Small parts of a larger antigen
B cells and T cells usually do not have the same epitope. Why not?
B cell binds the native molecules that are floating around outside of cells while T cell must have a peptide presented to it.
