Defining the transcriptional signature of esophageal-to-skin lineage conversion

Abstract

The ability of epithelial cells to rewire their cell fate program beyond their physiological repertoire has become a new paradigm in stem cell biology. This plasticity leaves behind the concept of strict stem cell hierarchies, opening up new exciting questions about its limits and underlying regulation. Here we developed a heterotypic 3D culture system to study the mechanisms modulating changes in the identity of adult esophageal epithelial cells. We demonstrate that, when exposed to the foreign stroma of adult skin, esophageal cells transition towards hair follicle identity and architecture. Heterotypic transplantation experiments recapitulated this cell fate conversion process in vivo. Single-cell RNA sequencing and histological analysis, capturing the temporality of this process, reveal that most esophageal cells switching towards skin identity remain in an intermediate state marked by a transient regenerative profile and a particularly strong hypoxic signature. Inhibition of HIF1a establishes the central role of this pathway in regulating epithelial cell plasticity, driving cells away from their transition state in favor of cell fate conversion.

Hypopharyngeal reconstruction using prelaminated autologous bio-engineered pectoralis major flaps

“…4. Биоптат мышечного среза через 3 недели преламинации с эквивалентом эпителиальной ткани: а -фрагмент мышечной ткани из зоны трансплантации, окраска гематоксилином и эозином, ×100; б -иммуногистохимическое исследование, экспрессия общих цитокератинов, окрашивание DAB, ×100; в -цитологическое исследование поверхности мышечного лоскута с готовым аналогом, окраска гематоксилином и эозином, ×1000; г -иммуногистохимическое выявление эпидермального фактора транскрипции p63 в ядрах клеток, окрашивание ДАБ, ×1000 правлении под влиянием стромы взрослой кожи [16]. [5].…”

Pre-cancerous Niche Remodelling Dictates Nascent Tumour Survival

“…To explore this, we assembled 3D heterotypic cultures in which healthy epithelia from untreated mice were grown ex vivo on denuded tumour stroma (lacking the epithelial compartment) from DEN-treated mice. Such an approach allowed us to investigate how pre-existing signals in the early tumour microenvironment affect epithelial cell behaviour 23 (Fig. 2a).…”

“…Size-matched Polydimethylsiloxane (PDMS) stencil frames were placed around the tissue construct to prevent cell expansion (see "Stencil production"). The tissue was settled for 10 min prior to adding 2 ml of minimal medium (mFAD), containing one-part DMEM (Fisher Scientific; 41966029) and one-part DMEM/F12 (Fisher Scientific; 11320033) supplemented with 5 μg/ml insulin (Sigma-Aldrich; 15500), 5 % foetal calf serum (Fisher Scientific; 26140079), 1 % P/S and 5 µg/ml Apo-Transferrin (Sigma-Aldrich; T2036), as per 23,58 . 3D heterotypic cultures were maintained in standard humidified cell culture incubators at 37°C with 5 % CO 2 for up to 7 days.…”

A Scarless Healing Tale: Comparing Homeostasis and Wound Healing of Oral Mucosa With Skin and Oesophagus

“…Interestingly, keratin expression programmes can change when epithelial cells are exposed to a different environment. Epithelial cells respond to extrinsic signals and change their identity when placed in a different microenvironment, as observed when oesophageal, thymic or cornea epithelial are placed on skin microenvironment (Ferraris et al, 2000;Bonfanti et al, 2010;Bejar et al, 2021). For instance, when oesophageal epithelial cells are grafted into skin, the suprabasal layers loose Krt4 expression as it transforms into a skin identity (Bejar et al, 2021).…”

“…While in full-thickness skin transplant into the oral cavity (to reconstruct tongue or buccal mucosa), the recipient organ keeps characteristics of the donor tissue ( Vural and Suen, 2000 ; Sebastian et al, 2008 ; Amin et al, 2011 ; Aslam-Pervez et al, 2018 ), there is mounting evidence that grafted epithelial cells can adopt the phenotype of the recipient tissue, stressing the plasticity of these cells and the importance of the underlying connective tissue and fibroblasts to determine epithelial cells phenotype. Recent animal work has successfully grafted oesophageal tissue into skin demonstrating that when exposed to the adult skin dermis, oesophageal epithelial cells transition to a skin identity following a cell fate conversion process ( Bejar et al, 2021 ). This highlights how the stromal cells influence the final epithelial phenotype in a homeostatic tissue.…”