Introduction:
Chronic lymphocytic leukemia(CLL) is the most common adult leukemia comprised 20-30% of leukemia cases in humans. It is a lymphoproliferative disorder characterized by the accumulation of clonal small mature lymphocytes with a characteristic surface phenotype. The clinical course is extremely variable, from a very indolent form to progressive one. CD38 expression correlates rapid time from diagnosis to progression requiring
treatment, poor response to therapy and inferior overall survival. It might be a biomarker for predicting VH mutational status in CLL patients and also appear to be involved in the pathogenesis of this disease. The aim of the study was to determine CD38 expression on B-cells in patients suffering from B-CLL designation of CD38+ and CD38- groups of patients at the moment of diagnosis. Results were compared to obtained in peripheral
blood samples of healthy subjects. We also assessed usefulness of this antigen in the diagnosis of B-CLL determining occurrence rate of CD38 in group of patients with 30% or more CD38 positive cells(group A) and patients with less than 30% CD38 cells(group B).

Material and methods:
Leucocytes from peripheral blood of 20 B-CLL patients (both male and female) were studied.The control group consisted of 20 healthy controls. Expression of CD38 on B-CLL cells was studied in all samples using a flow cytometer FascCalibur(Becton Dickinson) and monoclonal antibody CD38 PE connection with CD19 FITC antigen.

Results:
Expression of CD38 on B-cells of chronic lymphocytic leukemia patients was significantly higher when compared to healthy subjects. We’ve designed two group of patients-with positive(CD38+) and negative(CD38-)expression of this antigen. Range of CD38 expression was 65,29% ± 17,06% for A group(>30% CD38+ lymphocytes) and
11,35% ± 7,62% for group B(<30% CD38+ lymphocytes).


Conclusions:
Our finding confirm the usefulness of CD38 expression in the diagnosis of B-CLL patients and high expression levels of this protein.