Lecture 6 flashcards
What are antigen
Proteins or carbohydtrares that engage immune system and initiates immune response.
explain the diffrent classes of that antigens can be made of
Proteins: mostly made from proteins
Polysaccharides:polysacchardies/lipopolysaccharides
lipids: non immunogenic may assists antigen-mediated immune activation.
Nucleic acid:poorly immunogenic
what are the different types of epitopes?
Linear: formed by specific sequence
Conformational: formed by 3-d structure.
what does polygenic mean and polymorphic.
several different MHC I and II alleles, therefore every individual has a set of MHC molecules with different ranges of peptide binding specificities Essential polygenic is many genes involved and polymorphic is many version of those genes
CD8+ T-cells recognizes?
MHC I
HLA-A, HLA-B, HLA-C
CD4+ T-cells recognize
MHC II
HLA-DR, HLA-DQ, HLA-DP
What is MHC haplotype
set of maternally- and paternally-derived MHC genes on each chromosome (3 MHCI, 3 MHCII from each parent – total of 12 make up your HLA “fingerprint”
Peripheral Dendritic cells:
travel from peripheral site to LN to
present antigens to T cells (can be monocyte derived)
Resident/ Follicular Dendritic cells (plasmacytoid and lmyphoid)
main role is sampling lymph fluid for opsonized antigens adn to activate b cells they can do this without mhc
What Roles of APC vary with location -macrophages
stay at sites of infection/inflammation and support the fight
at the site of infection, also re-stimulate T cells that have arrived from LN
at peripheral sites of inflammation.
in order for T-cells to become fully activated by an antigen-presenting cell (APC), three signals are necessary, what are they.
signal 1:TCR recognises and binds to peptides presented on MHC of APC
Signal 2: Co stimulation
signal 3: cytokein signaling recieve type and strength of immune response.
treg function includes
Control/ dampen immune response
Maintain tolerance to self antigens
Prevent autoimmune disease
What do seconday lymphoid organs consist of
lymph nodes
spleen
Galt: gut-associated lymphoid tissue
BALT:bronchial-associated lymphoid tissue
MALTmucosal-associated lymphoid tissue
What are Langerhans cells
immature dendritic cells found in the skin.
What happens to CD4 T cells in terms of trafiking
Some stay in ln to help activate b and cd8 cells while other go to indection sight
