OP0186 #EULAR2021 by Dr. Mariele Gatto. Anti-cancer effect of immunotherapy with ICI is believed to be mediated by CD8 positive Tc cells. It is not known if other cells get activated. This study looks at B cells. Transitional B cells ⬆️ in ICI induced arthritis (CP-IA). /TK https://t.co/szFF81SKVL