Apoptosis of Peripheral Blood Mononuclear Cells in Different Ages of Normal Children

ABSTRACT

PURPOSE: To survive in an ecological environment, an individual must develop immunity to various antigens. Therefore, populations of peripheral blood mononuclear cells (PBMC) in humans change continuously with growth. The object of this study is to evaluate the apoptosis of peripheral blood mononuclear cells (PBMC) in normal children of different ages. METHODS: PBMC were isolated from the study groups. Ten cord blood samples of normal babies, 10 blood samples of normal children each from 4 different age groups (0-1, 2-5, 6-10, 11-15 year- old and adult), and 20 from normal adults were included in this study. After 24 and 48 hrs incubation in RPMI1640 media containing 10% fetal calf serum, cells were stained with Annexin V and PI and then analyzed with FACScan flowcytometer. RESULTS: Cord blood mononuclear cells showed the lowest percentage of apoptosis compared to other age groups. PBMC isolated from the 0-1 year-old normal children showed the highest percentage of apoptosis, and the percentage of apoptosis decreased with increase of age. After the age of 10, the percentage of PBMC apoptosis was the same as that of adults. CONCLUSION: The differences in the percentage of PBMC apoptosis with different age groups might be from immunologically different state of the hosts with different age. This result could be a useful reference data for the study of apoptosis in pediatric disease in the future.