TAP1-independent loading of class I molecules by exogenous viral proteins.
Presentation of peptides derived from endogenous proteins on class I molecules needs functional TAP peptide transporters. To reveal whether class I-associated presentation of exogenous proteins also required the presence of TAP transporters, we assessed in vitro the ability of spleen cells and macrophages from TAP1-deficient mice (TAP1-/-) to present peptides derived from exogenous recombinant viral proteins on their class I molecules. We found that recombinant glyco- and nucleoprotein from lymphocytic choriomeningitis virus and nucleoprotein of vesicular stomatitis virus were presented as efficiently by TAP1-/- cells as by control cells. Peptide regurgitation was not involved. Since particulate, non-replicating antigens can efficiently prime anti-viral cytotoxic T cells in vivo, this new, TAP-independent pathway of class I-associated antigen presentation may be applicable for vaccine strategies.
Bachmann
M F
MF
Department of Pathology, University of Zürich, Switzerland.
Oxenius
A
A
Pircher
H
H
Hengartner
H
H
Ashton-Richardt
P A
PA
Tonegawa
S
S
Zinkernagel
R M
RM
D000818:Animals; D017951:Antigen Presentation; D002478:Cells, Cultured; D015395:Histocompatibility Antigens Class I / Q000276:immunology / Q000378:metabolism*; D008264:Macrophages / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D008817:Mice, Mutant Strains; D009842:Oligopeptides / Q000235:genetics / Q000378:metabolism*; D013154:Spleen / Q000276:immunology; D014764:Viral Proteins / Q000276:immunology* / Q000378:metabolism
D015395:Histocompatibility Antigens Class I; D009842:Oligopeptides; D014764:Viral Proteins; C080396:trypsinogen activation peptide