SH3BP2 and Arthritis: The severity of arthritis was significantly higher in arthritic Sh3bp2KI/+ mice compared with arthritic Sh3bp2+/+ mice at day 35–42 (12.83±1.02 in Sh3bp2KI/+ vs. 8.07±0.94 in Sh3bp2+/+ at day 42) (Figure 2C).