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