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Updated: Jun 22, 2026

Preparation and Applications of Organotypic Thymic Slice Cultures
Published on: August 6, 2016
Why does the thymus involute? A selection-based hypothesis
Mark R Dowling1, Philip D Hodgkin
1Immunology Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3050, Australia.
Abstract:
Thymic involution remains a fundamental mystery in immunology. Here we present an argument that this seemingly counterproductive behavior may have evolved to allow for peripheral selection of a T-cell repertoire during young-adult life, optimized for fighting infections and avoiding reaction to self. Age-associated decline in immune function may be viewed as an unfortunate side effect of this selective process. Thus, the key to understanding thymic involution might lie in a more quantitative understanding of T-cell homeostasis in the periphery.
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