Harper R A, Grove G
Science. 1979 May 4;204(4392):526-7. doi: 10.1126/science.432659.
Papillary fibroblasts, when compared to reticular fibroblasts from the same skin specimen, exhibit greater proliferative capacities in vitro. These results demonstrate a difference in function between morphologically similar cells obtained from the same tissue. Such findings represent an important consideration in the study of cell aging in vitro.