Figure 2

Ex vivo analysis of the development of the A12-specific T-cell response in DR1 Tg mice. DR1 mice were immunized with either A12 or OVA, and individual mice were killed on day 10 after immunization. Cells from inguinal lymph nodes were collected and either analyzed immediately (a, b) or stimulated for 4 days with the A12 peptide or Ova before analysis (c, d). (Lower panel) DR1 mice were immunized with either CII/CFA (e) or Ova (f) and, at the time of onset of arthritis, were treated subcutaneously (100 μg/mouse in IFA) with either A12 peptide (e) or Ova (right) (f). Cells were collected from inguinal lymph nodes on day 26 after treatment with peptide, and the cells were analyzed for the presence of tetramer-positive cells directly ex vivo with flow cytometry. All cells were analyzed for the presence of A12-specific T cells by using the DR1-A12 tetramer and anti-CD3 or anti-CD4, anti-CD8, and anti-CD19. Anti-CD8 and anti-CD19 were used simultaneously in the FL4 channel, and anti-CD3 or anti-CD4 was used in the FL1 channel. The cells represented are CD19^-/CD8^-/CD3⁺ or CD19^-/CD8^-/CD4⁺. Data are representative of at least six mice per time point and are based on a minimum of 100,000 cells analyzed.