CC Chemokine Receptor 4-Positive CD4⁺ Lymphocytes in Peripheral Blood Increases during Maturation in Healthy Beagles

Abstract

In this study, percentages of CCR4⁺ cells in peripheral CD4⁺ T-lymphocytes were examined with flow cytometry in 46 healthy beagles between 3 months and 7 years of age. The percentage of CCR4⁺ cells varied from 9.9% to 33.5%. The mean percentage was significantly lower in the group with ages of less than 1 year than those with ages equal to or more than 1 year (p<0.05), suggesting that maturation might increase the CCR4⁺ T-lymphocyte subset. No influence of aging on the percentages was detected among the groups with ages equal to or more than 1 year. The findings are useful for establishing a reference value for the percentage of peripheral CCR4⁺CD4⁺ lymphocytes in dogs.