The effects of aging, sex, and tumor burden on the peripheral blood immune cell profile and absolute counts.

Abstract

Background: To better assess the peripheral immune status and aid in the early diagnosis and prognosis of tumors, we compared the proportion and absolute counting of peripheral immune cell subsets in healthy individuals and tumor patients of varying ages, taking into account the impact of sex and tumor metastasis. Methods: We used peripheral blood mononuclear cell (PBMC) samples from 520 patients with various tumor types and 109 healthy volunteers. The absolute numbers of lymphocytes and monocytes were identified by an automated blood analyzer, and multi-parameter flow cytometry was used to examine the subsets of natural killer (NK) cells (CD3-CD16+CD56+), T cells (CD3+CD4+/CD8+), and mononuclear cells (CD14+) in PBMC. Results: The percentage of T cells (CD3+) in peripheral blood mononuclear cells (PBMC) was 55.83% VS 45.54% (P<0.0001) between healthy volunteers and tumor patients, showing a significant downward trend. Meanwhile, the percentages of monocytes (CD14+) and NK cells (CD3-CD16+CD56+) showed a significant upward trend. Single factor or multifactor analysis yielded identical findings on the proportion of PBMC between healthy individuals and patients with different malignancies, considering the three confounding variables of age, sex, and tumor metastasis. Conclusion: The proportion and absolute counting of acquired immune T cells, innate immune NK cells, and monocytes in PBMCs all exhibit substantial changes between cancer patients and healthy individuals, and the differences are influenced by age, sex, and tumor progression.