Immunophenotypes in peripheral blood of children in pre-school age: reference values

Abstract

The immune system during human development undergoes changes due to maturity and exposure to antigens. The objective of this study is to evaluate leukocyte populations and lymphocyte subpopulations in health children. Peripheral blood was obtained to identify leukocytes, memory (CD45RO+) and effector cells. A total of 102 preschoolers were analyzed; those from four to five years presented a decrease in leukocytes and naïve cells (CD4+CD45RA), in relation to children from six to 24 months. Children from 25 to 48 months showed a decrease in CD8+ CD45RA+, compared to children aged 6 to 24 months. The Natural Killer ncreased in the group from 25 to 48 months. Other increased subpopulations were CD8+, CD3+CD45RO+, and CD4+CD45RO+ in children aged 49 to 60 months. In those from 25 to 48 months, the CD4+CD45RA+CD45RO+, CD8+CD45RA+CD45RO+, and CD8+CD45RO+ were found to be increased. As a conclusion, the populations of leukocytes and lymphocytes showed statistically significant changes, regarding the chronology of their ages of Mexican children.