Single-Cell Transcriptomics Uncover Key Regulators of Skin Regeneration in Human Long-Term Mechanical Stretch-Mediated Expansion Therapy

Yidan Sun; Luwen Xu; Yin Li; Jian Lin; Haizhou Li; Yashan Gao; Xiaolu Huang; Hainan Zhu; Yingfan Zhang; Kunchen Wei; Yali Yang; Baojin Wu; Liang Zhang; Qingfeng Li; Caiyue Liu

doi:10.3389/fcell.2022.865983

Single-Cell Transcriptomics Uncover Key Regulators of Skin Regeneration in Human Long-Term Mechanical Stretch-Mediated Expansion Therapy

Front Cell Dev Biol. 2022 May 30:10:865983. doi: 10.3389/fcell.2022.865983. eCollection 2022.

Authors

Yidan Sun¹, Luwen Xu¹, Yin Li², Jian Lin³, Haizhou Li¹, Yashan Gao¹, Xiaolu Huang¹, Hainan Zhu¹, Yingfan Zhang¹, Kunchen Wei¹, Yali Yang^{4

5}, Baojin Wu⁶, Liang Zhang^{2

7}, Qingfeng Li¹, Caiyue Liu¹

Affiliations

¹ Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
² CAS Key Laboratory of Tissue Microenvironment and Tumor, Shanghai Institute of Nutrition and Health, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China.
³ Department of Orthopedics, Shanghai Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
⁴ Department of Dermatology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
⁵ Department of Laser Cosmetology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
⁶ Department of Plastic Surgery, Shanghai Huashan Hospital, Fudan University School of Medicine, Shanghai, China.
⁷ Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, China.

Abstract

Tissue expansion is a commonly performed therapy to grow extra skin in vivo for reconstruction. While mechanical stretch-induced epidermal changes have been extensively studied in rodents and cell culture, little is known about the mechanobiology of the human epidermis in vivo. Here, we employed single-cell RNA sequencing to interrogate the changes in the human epidermis during long-term tissue expansion therapy in clinical settings. We also verified the main findings at the protein level by immunofluorescence analysis of independent clinical samples. Our data show that the expanding human skin epidermis maintained a cellular composition and lineage trajectory that are similar to its non-expanding neighbor, suggesting the cellular heterogeneity of long-term expanded samples differs from the early response to the expansion. Also, a decrease in proliferative cells due to the decayed regenerative competency was detected. On the other hand, profound transcriptional changes are detected for epidermal stem cells in the expanding skin versus their non-expanding peers. These include significantly enriched signatures of C-FOS, EMT, and mTOR pathways and upregulation of AREG and SERPINB2 genes. CellChat associated ligand-receptor pairs and signaling pathways were revealed. Together, our data present a single-cell atlas of human epidermal changes in long-term tissue expansion therapy, suggesting that transcriptional change in epidermal stem cells is the major mechanism underlying long-term human skin expansion therapy. We also identified novel therapeutic targets to promote human skin expansion efficiency in the future.

Keywords: AREG–EREG ligands; c-fos; epithelial to mesenchymal transformation; mechanical stretch; single cell RNA sequence; skin regeneration; tissue expansion.