Flashcards in Ch 1 Immune Mechanisms Deck (29):
genes that encode MHC are located on what chromosome? B2 microglobulin?
6 (short arm); 15
what order are the regions of MHC molecules encoded on chrom 6?
class II (HLA -DP, DQ, DR) class III, and class I (HLA- a,b,c)
what does class III MHC polypeptide region encode?
complement (Factor B, C4, C2); TNFa, lymphotoxin a & b; HSP
besides MHC II peptides, what other proteins are encoded on chrom 6 class II region
HLA-E (NK cell recognition), HLA-F (localized to ER and Golgi), HLA-G (on fetal derived placental cells), HLA-H (iron metabolism)
How do HSV and CMV evade MHC I presentation?
block TAP; remove class I molecule from ER, respectively
in MHC II processing, what occupies the binding cleft and what protein facilitates?
in ER, invariant chain is in binding cleft, cleaved to CLIP in vesicle by proteolytic enzymes, then HLA-DM (intracellular protein) removes CLIP for peptide to be bound
immune dysregulation due to mutation in foxp3; characterized by watery diarrhea, eczema and endocrinopathy
what is Bim?
pro-apoptotic factor in the BCL2 family. activated by t cells binding self-antigen without costimulation. apoptosis occurs through mitochondrial pathway
what does FasL do?
FasL (cd95L) binds with Fas (cd95) on same or nearby cells when t cell is self reactive. leads to apoptosis via caspase cascade
what is Alps caused by and what is it?
mutation in Fas or caspase 10; lymphocytes don't know when to die and they accumulate in lymph tissue and there are autoimmune problems
What is the receptor for CCL5 (RANTES)
CCR1, 3, 5
CCR4 (pro Th2 response)
mutation in what confers malaria protection?
DARC/duffy (mutation in GATA of DARC gene)
CD54 binds LFA1 and MAC1, binding for Rhinovirus A and B
CD102 binds LFA1
cd50 binds LFA1 and CD18
CD 242 binds LFA1 and CD18
cd106 binds VLA4 (a4B1); vascular
CD 31 binds CD 31 and 38; platelets
binds mucosal addressin (a4B7); mucosa; important for gut homing
CD 56 binds VLa4 (a4B1); neuronal
chemokine associated with heparin induced thrombocytopenia
how is CCR5 related to HIV?
homozygous - NO infection; heterozygous - slow progression
considered T trophic in HIV
CCL3L1 and HIV
low level leads to higher HIV acquisition, high viral load, worse disease; also known as fractalkine and can predispose to atherosclerosis