title: T cell antigen discovery using soluble vaccinia proteome reveals recognition of antigens with both virion and nonvirion association.
abstract: Vaccinia virus (VACV) is a useful model system for understanding the immune response to a complex pathogen. Proteome-wide Ab profiling studies reveal the humoral response to be strongly biased toward virion-associated Ags, and several membrane proteins induce Ab-mediated protection against VACV challenge in mice. Some studies have indicated that the CD4 response is also skewed toward proteins with virion association, whereas the CD8 response is more biased toward proteins with early expression. In this study, we have leveraged a VACV strain Western Reserve (VACV-WR) plasmid expression library, produced previously for proteome microarrays for Ab profiling, to make a solubilized full VACV-WR proteome for T cell Ag profiling. Splenocytes from VACV-WR-infected mice were assayed without prior expansion against the soluble proteome in assays for Th1 and Th2 signature cytokines. The response to infection was polarized toward a Th1 response, with the distribution of reactive T cell Ags comprising both early and late VACV proteins. Interestingly, the proportions of different functional subsets were similar to that present in the whole proteome. In contrast, the targets of Abs from the same mice were enriched for membrane and other virion components, as described previously. We conclude that a "nonbiasing" approach to T cell Ag discovery reveals a T cell Ag profile in VACV that is broader and less skewed to virion association than the Ab profile. The T cell Ag mapping method developed in the present study should be applicable to other organisms where expressible "ORFeome" libraries are also available, and it is readily scalable for larger pathogens.
authors.affiliation: Division of Infectious Diseases, School of Medicine, University of California, Irvine, Irvine, CA 92697; Antigen Discovery, Inc., Irvine, CA 92618; and ddavies@uci.edu.
authors.forename: D Huw
authors.initials: DH
authors.lastname: Davies
authors.affiliation: Division of Infectious Diseases, School of Medicine, University of California, Irvine, Irvine, CA 92697;
authors.forename: Sookhee
authors.initials: S
authors.lastname: Chun
authors.affiliation: Antigen Discovery, Inc., Irvine, CA 92618; and.
authors.forename: Gary
authors.initials: G
authors.lastname: Hermanson
authors.affiliation: Division of Hematology and Oncology, School of Medicine, University of California, Irvine, Irvine, CA 92697.
authors.forename: Jo Anne
authors.initials: JA
authors.lastname: Tucker
authors.affiliation: Division of Infectious Diseases, School of Medicine, University of California, Irvine, Irvine, CA 92697;
authors.forename: Aarti
authors.initials: A
authors.lastname: Jain
authors.affiliation: Division of Infectious Diseases, School of Medicine, University of California, Irvine, Irvine, CA 92697;
authors.forename: Rie
authors.initials: R
authors.lastname: Nakajima
authors.affiliation: Division of Infectious Diseases, School of Medicine, University of California, Irvine, Irvine, CA 92697; Antigen Discovery, Inc., Irvine, CA 92618; and.
authors.forename: Jozelyn
authors.initials: J
authors.lastname: Pablo
authors.affiliation: Division of Infectious Diseases, School of Medicine, University of California, Irvine, Irvine, CA 92697;
authors.forename: Philip L
authors.initials: PL
authors.lastname: Felgner
authors.affiliation: Antigen Discovery, Inc., Irvine, CA 92618; and.
authors.forename: Xiaowu
authors.initials: X
authors.lastname: Liang
mesh_terms: D000818:Animals; D000956:Antigens, Viral / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D056724:Immunity, Humoral; D007114:Immunization; D007371:Interferon-gamma / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D020543:Proteome / Q000276:immunology*; D011948:Receptors, Antigen, T-Cell / Q000276:immunology*; D013154:Spleen / Q000166:cytology; D018417:Th1 Cells / Q000276:immunology; D018418:Th2 Cells / Q000276:immunology; D014616:Vaccinia virus / Q000276:immunology*
chemical_list: D000956:Antigens, Viral; D020543:Proteome; D011948:Receptors, Antigen, T-Cell; D007371:Interferon-gamma