T cell specificity to the CII259-273 epitope and its posttransationally modified forms in B10.DR4.Ncf1*/* mice following immunization with huCII. Experimental animals were immunized with 100 μ g huCII emulsified in CFA at day 0. Twenty-one days later the mice received a booster immunization of 50 μ g huCII in IFA. At four particular time points after immunization (day 15, 35, 50, 65) five mice per group were sacrificed and inguinal lymph nodes were harvested for further analysis. (A) T cell recall responses in huCII-immunized B10.DR4.Ncf1*/* mice following in vitro restimulation with CII259-273 peptides. Mean IFN-γ values for the conA positive control at each time point: d. 15 - 2.884 ± 0.313 ng/ml; d. 35 - 2.137 ± 0.485 ng/ml; d. 50 - 4.732 ± 0.53 ng/ml; d. 65 - 4.632 ± 0.291 ng/ml. Responses that are significantly higher than the GalOK264 response were marked with '*'. Background IFN-γ values are subtracted from the presented data. (B) Total CII-specific antibody levels in B10.DR4.Ncf1*/* mice immunized with huCII. (C) CII epitope-specific antibody levels B10.DR4.Ncf1*/* mice immunized with huCII. Data designate mean ± SE. *, P <.05; **, P <.01; ***, P <.001. CFA, complete Freund's adjuvant; con A, concanavalin A; (hu)CII, (human) collagen type II; IFA, incomplete Freund's adjuvant; IFN, interferon.