Effect of ionizing radiation on development process of T-cell population lymphocytes in Chernobyl children

Background: The aim of preliminary study was determined development process status of T-cell population lymphocytes in Ukrainian children after 22 years from Chernobyl accident for next feasibility study. Material and Method: 150 participants aged 6 to 16 years are included in three groups: Group I (n=65), 30 to 60 km from center accident at zone 3th, Group II (n=65) 60 to 90 km from same location at zone 4th and control group (n=20) from Kiev, 100 km from same location. Peripheral blood leukocytes from buffy coats were analyzed for T-lymphocytes population such as T-lymphocytes (CD3), T-helper (CD4) and T-cytotoxic (CD8) by roseting method using erythrocytes that conjugated with monoclonal antibody against CD3, CD4, and CD8 receptors then CD4/CD8 ratio were calculated. Results: Percentage of CD3 and CD4 in groups II and I decreased significantly in compared to control group at P<0.001. Percent of CD8 decreased significantly in group I compared to control group at P <0.001. CD4/ CD8 ratio decreased significantly in-group I comparison to control group at P=0.02. Leucocytes count in groups II and I have not changed significantly in comparison to control group (P=0.09,P=0.4) but in group II, it was significantly different in comparison to group I at P <0.008. Conclusion: Our data show that after 2 decade of Chernobyl accident, ionizing radiation may have affected the developmental processes of T-cell population. Iran. J. Radiat. Res., 2009 7 (3): 127-133