Virtually no IL-10-expressing plasma cells or plasmablasts (LAG-3+ plasma cells [Lino et al., 2018] and CD138+CD44+ plasmablasts [Matsumoto et al., 2014]) were detected in the spleen or DLNs following the induction of arthritis (Figures S1B–S1H). Here, SDC1 is linked to Arthritis.