Age-Dependent Normalization Functions for T Lymphocytes in Healthy Individuals

Area of Science:

• Immunology
• Biostatistics
• Human Physiology

Background:

• Lymphocyte counts change significantly with age, particularly in children.
• Existing normalization functions are limited and often exclude pediatric data.
• Accurate reference data is crucial for understanding lymphocyte dynamics in health and disease.

Purpose of the Study:

• To develop novel normalization functions for T lymphocyte (CD3+, CD3+CD4+, CD3+CD8+) counts and percentages across a wide age range (0-62 years).
• To establish reference trajectories for lymphocyte dynamics in a healthy Dutch population.
• To provide tools for quantifying lymphocyte changes in longitudinal studies, including disease states like HIV.

Main Methods:

• Analysis of cross-sectional data from 673 healthy Dutch individuals.
• Fitting lymphocyte subset data (naive and memory T cells) using a delayed exponential function.
• Modeling absolute cell counts derived from percentages and total lymphocyte counts.

Main Results:

• A delayed exponential function accurately described T lymphocyte trajectories.
• Parameter estimates were obtained for each T cell subset, reflecting both count and percentage changes.
• T lymphocyte counts showed an increasing trend in the first six months of life.

Conclusions:

• The study provides robust functions for T lymphocyte counts and percentages in the Dutch population.
• These functions serve as essential references for studying T lymphocyte dynamics in various diseases.
• The developed models enable precise quantification of lymphocyte changes in longitudinal studies, aiding clinical insights.