Two-Cell Assemblage Assay: A Simple In Vitro Method for Screening Hair Growth-Promoting Compounds

November 2020 in “ Frontiers in Cell and Developmental Biology ”

Sunhyae Jang, Jungyoon Ohn, Byungjun Kang, Minji Park, Kyu Han Kim, Ohsang Kwon

From the encyclopedia

Minoxidil →

An essential vasodilator with some anti-androgenic effects

Valproic acid →

an anticonvulsant repurposed for hair loss via histone inhibition

Tofacitinib →

a JAK inhibitor for alopecia areata and other autoimmune conditions

Studysummary This study introduced a simple and reliable in vitro assay capable of large-scale simultaneous screening of hair growth-promoting compounds using a 3D co-culture system of human dermal papilla and outer root sheath cells. Our plain-language summary of this paper — not a Tressless recommendation.

The document details the creation of the "Two-Cell Assemblage" (TCA) assay, a novel in vitro method for identifying hair growth-promoting compounds. This assay utilizes a 3D co-culture of human dermal papilla (hDP) cells and human outer root sheath (hORS) cells, which together form a structure that elongates over time, especially when treated with hair growth-promoting agents. The study validated the assay by applying known hair growth compounds (minoxidil, valproic acid, purmorphamine, and tofacitinib) and observed a dose-dependent increase in both the length of the TCA and the expression of hair growth-related genes (VEGF, HGF, IGF1, FGF7, FGF10, PDGFA, and PDGFB). Despite its simplicity and high-throughput capability, the authors note that the TCA assay does not completely replicate the in vivo hair follicle environment and suggest incorporating additional cell types and structures in future models. The study included human participants who provided informed consent.

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Research cited in this study

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