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Updated: Feb 25, 2026

Rapid Genetic Analysis of Epithelial-Mesenchymal Signaling During Hair Regeneration
Published on: February 28, 2013
The patch assay reconstitutes mature hair follicles by culture-expanded human cells
Qun Zhang1,2, Tingjian Zu2, Qian Zhou2
1Suzhou Institute of Shandong University, Building H of NUSP, 388 Ruoshui Road, Suzhou Industrial Park, Suzhou, Jiangsu, China.
Aim:
We tested whether the a simple injection known as the patch assay could reconstitute mature hair follicles by culture-expanded human cells and explored whether the assay could reflect the trichogenicity of cultured cells.
Materials & Methods:
Dissociated culture-expanded fetal or adult scalp dermal cells combined with foreskin keratinocytes were subcutaneously injected into the back skin of immunosuppressive mice to form the patch skin. The patches were collected and characterized and were analyzed for hair formation efficiency.
Results:
Using culture-expanded human fetal cells, the patch assay can efficiently reconstitute mature hair follicles and the efficiency of hair formation in the patch assay correlates with cell trichogenicity.
Conclusion:
The patch assay has the potential for testing the trichogenicity of human cells.

