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Updated: May 9, 2026

Analyzing the Functions of Mast Cells In Vivo Using 'Mast Cell Knock-in' Mice
Published on: May 27, 2015
[Age-related changes in mast cells and eosinophils of human dermis]
Abstract:
In this study, quantitative analysis of inflammatory effectors--mast cells and eosinophils--in derma of people of different ages is performed. The study shows that mast cell quantity in derma increases with age. Eosinophils are rarely observed in human dermis. There are no age-correlated changes of dermal eosinophils quantity observed. Age-correlated dermal fibroblast quantity is established. PCNA+ fibroblast percentage demonstrating their proliferative pool also reliably decreases with age. Results of correlation analysis show that age-correlated increase in mast cells' quantity is reliably correlated with decrease in total number and percentage of PCNA+ fibroblasts in derma. Consequently, age-correlated increase in dermal mast cell may be proposed to be one of the inflammatory and aging mechanisms. Mast cells, whose number increases with aging, may influence dermal fibroblast number with aging.
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