Similarly to B cells, an expanded T cell (CD3+) population expressing GM-CSF was seen in RA patients (3.4 ± 1.6%, n = 40) compared with both disease (1.7 ± 1.3%, n = 31, p < 0.0001) and healthy (0.6 ± 0.6%, n = 16, p < 0.0001) controls (Figure 1G). This evidence concerns the gene CSF2 and rheumatoid arthritis.