Using a cut-off value for anti-LtxA positivity defined by ROC, patients with early RA showed an increased frequency of anti-LtxA IgM antibodies when compared with PH (12.6% vs. 1.4%, respectively; p = 0.005) and controls (12.6% vs. 3.9%, respectively; p < 0.001) (Table 1). Here, CD40LG is linked to rheumatoid arthritis.