1Department of Immunology, School of Public Health, Medical Sciences /Tehran University, Tehran, Iran
2Immune and Gene Therapy Lab, Cancer Center Karolinska, Karolinska Hospital, Stockholm, Sweden
3Monoclonal Antibody Research Center, Avesina Research Institute
4Clinic of Hematology and Oncology, Firozgar Hospital, Faculty of Medicine, Iran University of Medical Sciences
5Clinic of Hematology and Oncology, Vali-Asr Hospital, Faculty of Medicine, Medical Sciences/ University of Tehran
6National Cell Bank of Iran, Pasteur Institute of Iran, Tehran, Iran
Background: Patients with B-cell chronic lymphocytic leukemia (B-CLL) have hetero-geneous clinical courses, thus several biological parameters need to be added to the cur-rent clinical staging systems to predict disease outcome. Recent immunophenotypic stud-ies performed mainly in Western populations have demonstrated the prognostic value of CD38 and ZAP-70 expression in B-CLL. Objectives: To investigate the expression pat-tern of a variety of membrane antigens on leukemic cells from Iranian patients with CLL and to find out if there are any differences in the expression of these markers between in-dolent and progressive groups. Methods: In the present study, peripheral blood samples from 87 Iranian patients with B-CLL were analysed by flow cytometry. Results: In all cases, the neoplastic cells displayed B-CLL phenotype (CD5+/CD19+/sIg+). The vast ma-jority of the cases expressed CD23, but failed to stain for CD3 or CD14. The leukemic cells of most patients expressed CD27 (84/87, 95.4%) and CD45RO (74/87, 83.9%) molecules, suggesting a memory B-cell phenotype. Comparison between the indolent (n=42) and progressive (n=37) patients revealed significantly higher frequency and inten-sity of CD38 expression in progressive group (40.5%) compared to indolent (11.9%) pa-tients (p<0.05). None of the other membrane antigens were differentially expressed in these two groups of patients. Conclusion: Our results obtained in an Asian ethnic popula-tion confirm and extend previous findings obtained from Western populations regarding the association of CD38 expression and disease progression in B-CLL.