Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2007-2-21
pubmed:abstractText
Influenza A virus-specific CD8+ T cell responses in H2(b) mice are characterized by reproducible hierarchies. Compensation by the D(b)PB1-F2(62) epitope is apparent following infection with a variant H3N2 virus engineered to disrupt the prominent D(b)NP(366) and D(b)PA(224) epitopes (a double knockout or DKO). Analysis with a "triple" knockout (TKO) virus, which also compromises D(b)PB1-F2(62), did not reveal further compensation to the known residual, minor, and predicted epitopes. However, infection with this deletion mutant apparently switched protective immunity to an alternative Ab-mediated pathway. As expected, TKO virus clearance was significantly delayed in Ab-deficient MHC class II(-/-) and Ig(-/-) mice, which were much more susceptible following primary, intranasal infection with the TKO, but not DKO, virus. CD8+ T cell compensation was detected in DKO, but not TKO, infection of Ig-deficient mice, suggestive of cooperation among CD8+ T cell responses. However, after priming with a TKO H1N1 mutant, MHC II(-/-) mice survived secondary intranasal exposure to the comparable H3N2 TKO virus. Such prime/challenge experiments with the DKO and TKO viruses allowed the emergence of two previously unknown epitopes. The contrast between the absence of compensatory effect following primary exposure and the substantial clonal expansion after secondary challenge suggests that the key factor limiting the visibility of these "hidden" epitopes may be very low naive T cell precursor frequencies. Overall, these findings suggest that vaccine approaches using virus vectors to deliver an Ag may be optimized by disrupting key peptides in the normal CD8+ T cell response associated with common HLA types.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0022-1767
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
178
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3091-8
pubmed:dateRevised
2007-12-3
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Hidden epitopes emerge in secondary influenza virus-specific CD8+ T cell responses.
pubmed:affiliation
Department of Immunology, St. Jude Children's Research Hospital, 332 N. Lauderdale Street, Memphis, TN 38105, USA.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural