Longterm Effects of Rituximab on B Cell Counts and Autoantibody Production in Rheumatoid Arthritis: Use of High-sensitivity Flow Cytometry for More Sensitive Assessment of B Cell Depletion

Abstract

In RA, clinical response to RTX is associated with the extent of B cell depletion and with autoantibody production. Changes in CD19+ B cell numbers correlate with those in disease activity and, in seropositive patients, also with IgM RF, but not with ACPA production. We found that hsFACS may be a useful method to more accurately assess incomplete B cell depletion.