FIG. 2.

Anti-CD20–mediated B-cell depletion strongly inhibits progression to overt diabetes development only when initiated in NOD mice that have not yet become IAA positive. A: Serum was collected from 10-week-old NOD female mice that then immediately began to receive treatments at 21-day intervals with the IgG1 CD20-specific or control antibody at a 10 mg/kg body wt dose. Serum samples were retrospectively assessed for the presence of IAAs and the mice monitored for diabetes development. Mice used for the analyses had a spread of eight separate birth dates and, thus, were entered into the treatment groups in a staggered fashion. Anti-CD20 treatment significantly suppressed diabetes development in the IAA-negative (P = 0.04) but not IAA-positive recipients (P = 0.14, Kaplan-Meier analyses). B: IAA-negative NOD female mice receiving a single anti-CD20 treatment at 10 weeks of age were not protected from subsequent diabetes development. Aby, antibody.