To understand the occurrence of arthritis by tolerized T cells or naïve T cells, as the theory speculates, the interaction of non-tolerized T cells rather than tolerized T cells could be the major reason for the immunogenicity of CII; Corthay et al. [52] developed a thymectomized adult mice model immunized with CII for 4 weeks in order to tolerate the T cells and found the occurrence of arthritis, which could be due to IFN-γ production by partially tolerant T cells with the help of B-cell though the existence of peripheral tolerance against the glycosylated CII 256–270 epitope. The gene discussed is IFNG; the disease is Arthritis.