BIOCHAP7A Flashcards
Pathogen:
an agent that causes disease
Antigen:
any molecule that may trigger an immune response
Non-self-antigen:
a molecule from outside the body that is recognized by the immune system and initiates an immune response. Also known as a foreign antigen
Major histocompatibility complex (MHC) markers:
on the surface of self-cells help the immune system distinguish them from non-self-material and prevent attacks.
MHC Class II:
expressed on antigen-presenting cells, which interact with T helper cells in the process of antigen-presentation.
Self-antigens
located on?
located on surface of cells, immune system does not attack them
self antigens
MHC class 1 markers:
expressed on all nucleated cells
self antigens
MHC class 2 markers:
found on specialized cells of immune system
Non-self-antigens
foreign, immune system attempts to eliminate it
if bacterium enters body, immune system recognizes specific bacterial proteins as foreign and attacks it
non sel antigens
MHC markers found on our cells are diff between individuals:
in organ transplants, class 1 makers expressed on doner will differ to organ receiver - triggers immune response to reject organ.
Malfunctions involving antigens
immune system will start attacking self-cells leading to autoimmune disease (allergies)
Types of pathogens
cellular
non cellular
have cellular structure and are living organisms
do not have a cellular structure and are non-living
extracellular threats:
intracellular:
threat found outside of a cell that can interfere with its function like bacteria
threat found within cell that can interfere with functioning like viruses that invade cell
