Figure 4

Pre-immunization of citBiP, and not native BiP, exacerbated collagen-induced arthritis (CIA) in mice. A. Serum levels of anti-BiP and anti-citBiP antibodies in control and CIA mice. Serum was obtained at 50 days after the first immunization. *: P < 0.05, ***: P < 0.001. B. Arthritis scores of CIA in complete Freund's adjuvant (CFA), BiP+CFA, and citBiP+CFA-pre-immunized mice (n = 10 each). *: P < 0.05. C. Histological CIA scores in CFA, BiP+CFA, and citBiP+CFA-pre-immunized mice (n = 10 each). *: P < 0.05. D. Serum levels of anti-CCP antibodies in CFA, BiP+CFA, and citBiP+CFA-pre-immunized mice (n = 10 each) after CIA development. *: P < 0.05, ***: P < 0.001. Data are representative of 3 trials and the arthritis scores for the other 2 sets of experiments are shown in Additional file 1. The horizontal lines indicate medians. P-values were calculated by Mann-Whitney U test.