Figure 4: Infected and RA-induced mice produce higher levels of serum anti-CII IgG1 and IgG2 antibodies. Levels of (a) anti-CII IgG1; and (b) IgG2a Abs were measured in all of the groups sera were obtained 15 days post-HAO injection. Significant differences were observed in the IgG1 Abs between the RA versus Tc + RA and Tc versus Tc + RA in 1 : 10 dilution and Control versus Tc + RA in the 1 : 10 and 1 : 20 dilutions. In the IgG2a Abs Control versus RA and Control versus Tc + RA showed significant differences in the 1 : 10 dilution. Statistical analysis, two-way ANOVA, * .