antigens and MHC Flashcards
define immunogen
able to provoke an immune response AND react with the products of response (antibodies, T cell receptors)
define antigen
reacts with products of immune response
autoantigens
self antigens (autoimmune disease). person’s own antibody (autoantibodies) reacts with one’s own antigen
alloantigens
antigens found in non-identical individuals of same species
allograft
human to human transplant
eg of alloantigens
A and B blood group antigens and HLA aka MHC
HLA/MHC fn
allows T lymphocytes to distinguish btwn self and non self
heterophilic or hetrogenic antigen
similar/identical antigens found on dissimilar
eg of hetrophilic antigen
Streptococcus and human cells in the heart/joints
epitotes aka
immunogenic or antigen determinants on antigen
fn of epitotes
interact with antigen binding site of an antibody or T cell receptor
structure of epitotes
four to six aa. small portions of immunogen/antigen distant in 1 structure but brought together by 2 3 and 4 structure
imp of epitotes
ID of unique epitotes essential to production of monoclonal antibodies and vaccines
define haptens
small low molecular weight substances. sugar, aa, drugs and metabolites
do haptens cause formation of antibodies
no not on their own
how do haptens become immunogenic
conjugate to protein carrier molecule
eg of hapten-carrier molecule
drugs attached to surface of platelets causes drug induced thrombocytopenia
where are MHC located on human chromosome
chromosome 6 except gene for beta2-microglobulin found on 15
which MHC classes encodes for complements
Class III gene
define MHC I and II
HLA. members of immunoglobin superfamily. include T cell receptors & antibodies
location of transmembrane protein
extend from cytoplasm through PM onto surface. eg HLA
which cell recognizes epitotes of antigen in class II MHC
t helper cells
which cell recognizes antigens in MHC I
T cytotoxic cells
structure of MHC I
3 alpha domains, 1 beta domain called Beta2microglobulin
