Immune Evasion Flashcards
Ad12 E1A
Inhibits MHC I heavy chain transcription and repressed TAP & LMP transcription. By preventing phosphorylation of NFKB by PKA
What does HBZ of HTLV do to avoid immune system
Represses tax transcription and takes over role in stimulating T cell proliferation. Tax is immunogenic presented on MHCs to CTLs
EBNA1 avoids proteasomal processing how
Gly ala repeats cis acting inhib signal for proteasomal degradation
And blocks own transcription - preventing DRiPs
What protein binds tap and prevents peptides binding?
HSV ICP47
What does HCMV US6 do?
Prevents ATP binding TAP therefore prevents peptide translocation (ATP energises)
How does HCMV affect ERAP1
miR-US4-1 targets ERAP1 mRNA 3’UTR
Which HCMV proteins target MHC1 to Proteasome
US2 - via TRC8 mediated ubi
US11 - via TMEM129 mediated ubi
Both lead to ERAD
Which adenovirus protein has dilysine motif that retains MHC I in ER
E3/19K (via cop1 vesicles)
What do K3 and K5 do?
Ubiquitinate cytosilic tail of MHC leads to endocytic pathway
Polyomaviruses do what to avoid CTL mediated lysis
miR that down regulates 2 transforming proteins that are antigenic ST and LT antigens
How does HIV avoid immune detection
Antigenic drift
Genome ~9000bps and error rate of synthesis RdDp 10-4 and retro viral genome synthesised by host cell RNAP - no proof reading
What protein in HIV binds to HLA-B27, and what mut stops this
P24 gag
Arg 264 to gly/ala
HMCV UL18?
Binds B2m and peptides and then LIR-1 inhibitory R
Which HCMV protein encodes a tap independent HLA-E ligand?
UL40
Homology to HLA-Cw304
HCMV UL16 works how?
Blocks cell surface exp of ULBP1&2 by retaining in ER
and of MICA by retaining in Golgi
