Summary
Cell-mediated immunity, measured by lymphocyte transformation tests, declines significantly with age. Older adults showed a notable decrease in immune responsiveness, with many exhibiting pathologically low values.
Area of Science:
- Immunology
- Gerontology
- Cell Biology
Background:
- Cell-mediated immunity is crucial for immune responses.
- Assessing immune function across different age groups is important for understanding age-related health changes.
Purpose of the Study:
- To evaluate cell-mediated immune reactivity in healthy individuals across different age groups.
- To determine the impact of aging on lymphocyte transformation response.
Main Methods:
- Utilized the lymphocyte transformation test (LTT) with phytohemagglutinin (PHA) as a mitogen.
- Quantified cell-mediated reactivity by measuring 2-(14)C-thymidine incorporation into DNA.
- Studied three age cohorts: up to 20 years, 21-40 years, and over 70 years, comprising 53 healthy subjects.
Main Results:
- Lymphocyte responsiveness significantly decreased with advancing age.
- The oldest age group (over 70 years) exhibited the most pronounced decline in immune function.
- Twelve subjects in the oldest cohort presented pathologically low lymphocyte transformation values, indicating impaired cell-mediated immunity.
Conclusions:
- Aging is associated with a significant reduction in cell-mediated immune responsiveness.
- The findings highlight potential age-related immune deficiencies in healthy elderly populations.
- Further research is warranted to explore the clinical implications of these age-related immune changes.
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