Primary immune thrombocytopenia (ITP) is a disorder caused by autoantibody-mediated
platelet destruction and decreased platelet production. Rituximab, a B cell–depleting agent,
has become the first-line treatment for ITP; however, patients with refractory disease usually
require splenectomy. We identified antibody-secreting cells as the major splenic B cell
population that is resistant to rituximab. The phenotype, antibody specificity, and gene
expression profile of these cells were characterized and compared to those of antibody …

B cells play an important role in the immune response and can lead to the development of
autoimmune diseases and particularly immune thrombocytopenia (ITP). A rational approach
to ITP treatment could involve B-cell depletion such as with rituximab. Rituximab is a
chimeric monoclonal antibody directed against CD20 molecule. It has direct effects on
antibody production and indirect effects on cellular immunity. Rituximab demonstrated an
overall response rate of 62.5% that lasted from 2–48 months. The ability of rituximab as an …