Summary
Introduction. A proportion of patients with acute B-lymphoblastic leukemia fails to achieve a remission or does not tolerate a standardized chemotherapy. Immunotherapy with anti-CD agents might be an indispensable supplement to the treatment of these patients. The aim of the study was to investigate the expression patterns of potential immunological targets (CD20, CD22 and CD33) in patients with B-ALL.
Methods. 57 adult patients with acute B-lymphoblastic leukemia treated at Vilnius University Hospital "Santariskiu Klinikos" were included in the study. Diagnostic and follow-up bone marrow samples were analyzed on FACS Canto flow cytometer.
Results. CD20 was found to be positive in 50.88% of patients: in 28.07% of cases its expression was dim, in 15.79% it was heterogeneous, and in 7.02% it was intermediate or bright. CD22 was positive in 94.74% of cases. Cases with a dim or intermediate expression predominated (49.12% and 36.84% respectively). CD33 was positive in 36.84% of patients. Dim expression of marker prevailed (19.3%).
Conclusions. As CD20 is expressed only in a half of cases and its expression was mostly dim, it could be used as a target for immuno-therapy only in selected patients. On the contrary, because of extensive prevalence, CD22 targeted therapy could be applied to virtually all patients with acute B-lymphoblastic leukemia. Some patients with a significant expression of CD33 could even benefit from anti-CD33 immunotherapy.
