Keywords
Peripheral blood
Lymphocyte subsets
Age correlation
Immune function
Submitted : 2026-01-25
Accepted : 2026-02-09
Published : 2026-02-24
Abstract
NK cells are an important subset of lymphocytes in the human immune system and play a key role in antiviral and anti-tumor immunity. In this paper, the distribution characteristics and dynamic changes of peripheral blood NK cells in healthy people were systematically reviewed, focusing on the influence of age, gender, ethnicity, and environmental factors. Studies have shown that NK cells show a relatively stable distribution ratio in healthy adults, while in the development stage of children, they show dynamic characteristics that increase with age. The receptor expression and function of NK cells in the elderly population showed an age-related downward trend, indicating that the quality of NK cells, rather than the quantity, was a key indicator of age-related immune changes. Different ethnic groups and high-altitude environments also had a significant impact on NK cell distribution. This paper not only summarizes the quantitative characteristics of NK cell distribution but also analyzes the mechanism of its functional phenotypic changes, provides a scientific basis for clinical immune assessment, and points out the direction for future basic research and clinical application of NK cells.
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