AntigenInfo Flashcards
location of presentation for antigens in connective or epithelial tissue?
in lymph nodes
location of presentation for antigens in blood?
in the spleen
conventional dendritic cells location
tissues
conventional dendritic cells TLRs
TLR 4, 5, 8
conventional dendritic cells cytokines
TNF, Il-6, IL-12
conventional dendritic cells function
induction of T cell response against most antigens
plasmacytoid dendritic cells location
blood and tissue
plasmacytoid dendritic cells TLRs
TLR 7 and 9
plasmacytoid dendritic cells cytokines made
IFN a and b
plasmacytoid dendritic cells function
antiviral innate immunity and induction of T cell response against viruses
mature dendritic cells ability
able to present peptide antigens to naive T cells in lymph nodes
dendritic cell role in Antigen presentation
can express MHC II, initates T cell response to protein antigens
macrophages role in antigen presentation
inducibly expresses MHC class II, leads to effector phase of cell mediated immune response
B lymphocytes role in antigen presentation
can express MHC class II, presents antigen to helper CD4+ cells
what can B cells recognize?
proteins, nucleic acids, polysaccharides, lipids and small molecule
what can T cells recognize?
must be very small peptide fragments, and relies on MHC to process an antigen into the small peptide fragments
How does a T cell bind a peptide fragment?
it binds the fragment and the MHC component that it recognizes
MHC Class I information
found in all nucleated cells in the body and display peptide antigens that are found within the cytoplasm of the cell
What T cell mainly recognizes the MHC class I?
mainly recognized by CD8 cells because these are the cytotoxic cells that will kill cells infected in cytoplasm
MHC Class II information
these are only found in antigen presenting cells..dendritic, macrophages and B cells
display antigens from microbes in vesicles in the infected cells
What T cell mainly recognizes the MHC class II?
since displaying antigens from vesicles in the cell, these are mainly recognized by the CD4 cells since they will require helper cells
MHC name in Humans
Human Leukocyte Antigens
What chromosome is MHC on?
chromosome 6
MHC Class I names
HLA-A, HLA-B, HLA-C
MHC Class I chains
alpha chain with peptide binding cleft (a1,2,3), and beta-2 micro globulin for stability
a3 binds cd8 cell
transporter associated antigen processing for MHC class I
Proteasome breaks up into small peptides which go to ER where they are combined with MHC class I complex and then packaged and sent to membrane
MHC Class II names
HLA-DP, HLA-DQ, HLA-DR
MHC Class II chains
alpha and beta of equal size, both in membrane and both involved in binding the peptide
b2 binds cd4 cell
MHC Class II peptide association
phagocytosed an antigen, ER has MHC class II molecules with an invariant chain in the binding site, once antigen there the invariant chain leaves and the peptide can bind and the MHC II complex can go to membrane for recognition by CD4 cells
co-dominant expression of MHC genes
both mom and dad genes are transcribed so means you have more possible MHC proteins to present
polymorphic MHC genes
many different alleles in population so likely we are all different in MHC
importance of slow off rate of peptides in MHC
gives plenty of time for T cells to recognize and proliferate
celiac disease
gluten allergy that leads to fatty diarrhea, weight loss, and vitamin deficiencies
autoimmune, some genetic linkage to HLA
etiology of celiacs disease
villous atrophy intestines
treatment of celiac disease
GF diet
serological evaluation for celiacs
often have autoantibodies of EMA-IgA (antiendomysial) and tTG-IgA (transglutaminase antibody) and can test for these to do diagnosis
also have antibody against gliadin (component of gluten)
people also use endoscopy and biopsy
type 1 diabetes
autoimmune destruction of beta cells that make insulin in pancreas
some genetic linkage to HLA
treat with exogenous insulin
symptoms of type 1 diabetes
polydipsia (increased thirst) Polyuria (increased urine), weight loss
hyperglycemia, diabetic ketoacidosis
Auto-antibody testing for Type 1 diabetes
look for antibodies of anti glutamic acid decarboxylase,
anti islet cell
anti insulin
celiac disease genetic links
HLA DQ2 and HLADQ8,
type 1 diabetes genetic links
HLA DQ and HLA DR
hyperacute organ rejection
immediate, due to pre-formed antibodies, like incompatibility of ABO blood types
thrombosis occurs, organ dies
not common anymore
acute organ rejection
week to months due to developing B and T cells to foreign organ
shows with vasculitis, treat with immunosupressants
chronic organ rejection
years long, due to T and B cells
leads to fibrosis or scarring and may need new transplant
graft versus host disease
bone marrow transplant where the marrow makes new donor T cells that are sensitive against recipients MHC class…many organs effected
Graft versus host disease presentation
rash, jaundice, diarrhea, hepatosplenomegaly
