CC chemokine receptor 4-positive CD4(+) lymphocytes in peripheral blood increases during maturation in healthy beagles

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.