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Updated: Jun 21, 2026

Isolation, Culture, and Characterization of Primary Dermal Fibroblasts from Human Keloid Tissue
Published on: July 28, 2023
The man behind the eponym: Hans Biberstein and follicular hyperplasia overlying dermatofibroma
Johanna Hamel1, Walter H C Burgdorf, Wolfgang Bräuninger
1Department of Dermatology, Johannes Gutenberg University, Mainz, Germany.
Abstract:
Hans Biberstein first described the basaloid follicular hyperplasia overlying dermatofibromas in 1923 and published his extensive observations on the subject in 1931. Part of Josef Jadassohn's department in Breslau, he was forced to leave German by the National Socialist regime and spent the rest of his career in New York. After a hiatus of 30 years, the dermatopathologic literature once again began addressing his seminal finding but never gave him proper credit. We suggest Biberstein's sign as an appropriate term for basaloid follicular hyperplasia overlying a dermatofibroma and as a small tribute to a pioneer dermatopathologist.
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