Objective: To guide clinical decision making, race-, age- and gender-specific reference ranges for lymphocytes and CD4+ T-cell subsets are required.
Methods: Single platform flow cytometry to determine reference intervals for lymphocyte subpopulations and CD4+ T-cell subsets in 196 healthy Han Chinese adults.
Results: The frequencies and absolute numbers of B cells were slightly lower in Han Chinese individuals of the Shanxi region than in individuals from Hong Kong, Germany and Singapore, while percentages and absolute numbers of NK cells were slightly higher compared with individuals from Hong Kong. CD4+/CD8+ T-cell ratios, CD4+ T cell percentages and Th2 cell counts were higher, while frequencies and numbers of CD8+ T cells, numbers of NK cells and percentages of Th1 cells were lower, in females compared with males. CD4+ T cell percentages, CD4+/CD8+ T-cell ratios, numbers of CD8+ T cells and Treg cells, and Th17/Treg cell ratios differed by age.
Conclusion: We established lymphocyte and CD4+ T-cell subset reference intervals for healthy Han Chinese adults of the Shanxi region. Ethnicity, gender and age affected lymphocyte subset composition.
Keywords: CD4+ T cell subsets; Lymphocyte subsets; age; ethnicity; flow cytometry; gender; reference ranges.