Figure 1a shows the time course of the CAIA experiments. Upon the CAIA induction, the WT mice displayed severe arthritis in both the forepaws and hindpaws, including the elbow and knee joints (Figure 1b). However, compared to the WT mice, Rab44-KO CAIA mice exhibited impaired arthritis phenotypes, such as edema and redness (Figure 1b). Quantification of arthritis scores revealed that Rab44-KO CAIA mice had an arthritis score approximately half that of WT CAIA mice (Figure 1c). This evidence concerns the gene RAB44 and arthritic joint disease.