Effects of cytokines on CD20 antigen expression on tumor cells from patients with chronic lymphocytic leukemia

Anti-CD20 antibody is an established treatment for low-grade non-Hodgkin's lymphoma (NHL). Augmenting the expression of CD20 antigen on the tumor cell s may increase the cell kill and therefore increase the effectiveness of th e antibody. To study this, we incubated peripheral blood lymphocytes from C LL patients with the following cytokines: EPO, SCF, TNF alpha, TGF beta, GM CSF, TPO, IL-1, IL-2, IL-3, IL-4, GCSF. CD20 expression was studied by flow cytometry at baseline, 24 and 72 h after exposure to these cytokines. Upre gulation of CD20 antigen expression was observed with IL-4, TNF alpha and G MCSF. (C) 2000 Elsevier Science Ltd. All rights reserved.