CD40LG and rheumatoid arthritis: We concluded that increased levels of IgM anti-HPT78−108 HNE, IgM anti-IGKC2−19, and IgM anti-IGKC2−19 HNE in serum can be used as diagnostic biomarkers of RA, and high levels of IgM anti-HPT78−108 HNE, IgM anti-IGKC2−19, and IgG anti-THRB328−345 are related to increased disease activity during RA development.