Changes with Advancing Age in the Cell Population of Human Skin

Abstract

Using human autopsy skin specimens from 144 Caucasian males, 172 Japanese males and 103 Japanese females at different ages ranging from infants to 94 years old, age changes in cellularity, vascularity and proportions of several cell types in connective tissue of the dermis were studied.
In the youngest age group, cellularity of the dermis was high, and the cells were constituted almost entirely by fibroblasts and macrophages. Cellularity in the dermis decreased with age.
The number of fibroblasts with dark nuclei increases in older age groups. The number of demonstrable mast cells also increases. The number of papillae in a given area decreases remarkably in the later decades. There is an apparent increase in percentage of lymphocyts with age. However, the increase is not significant according to analysis by the Tukey methods.
With the exception of the number of fibroblasts with dark nuclei, the difference in number of all types of cells between Japanese males and females are not significant.
However, difference between two races (Caucasian males and Japanese males) are significant statistically with a few exceptions. The difference in the age change in number of several types of cells, as between the two races, are significant.