FOXP3 and arthritic joint disease: Results from NR4A1-KO mice indicate that inflammatory Ly6Chigh monocytes contribute to a mouse model of arthritis; in NR4A wild-type mice, CsnB increases levels of CD4+, CD25+, and FOXP3+ Treg cells in the presence of Ly6Clow monocytes to inhibit progression of arthritis [144].