Tape strips in dermatology research Hughes, A. J.; Tawfik, S. S.; Baruah, K. P. ...
British journal of dermatology (1951),
July 2021, Letnik:
185, Številka:
1
Journal Article
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Summary
Tape strips have been used widely in dermatology research as a minimally invasive method to sample the epidermis, avoiding the need for skin biopsies. Most research has focused on epidermal ...pathology, such as atopic eczema, but there is increasing research into the use of tape strips in other dermatoses, such as skin cancer, and the microbiome. This review summarizes the technique of tape stripping, and discusses which dermatoses have been studied by tape stripping and alternative minimally invasive sampling methods. We review the number of tape strips needed from each patient and the components of the epidermis that can be obtained by tape stripping. With a focus on protein and RNA extraction, we address the techniques used to process tape strips. There is no optimal protocol to extract protein, as this depends on the abundance of the protein studied, its level of expression in the epidermis and its solubility. Many variables can alter the amount of protein obtained from tape strips, which must be standardized to ensure consistency between samples. No study has compared different RNA extraction techniques, but our own experience is that RNA yield is optimized by using 20 tape strips and the use of a cell scraper.
What is already known about this topic?
Tape strips have been widely used in dermatology research as a minimally invasive method to collect epidermal samples.
Tape strips can be used as an alternative to skin biopsies in certain circumstances.
Tape strips can be used to determine protein, RNA, lipid and microbial expression.
There is currently no standardized protocol used for collecting and processing tape strips.
What does this study add?
This review summarizes the technique of tape stripping, what information can be obtained from tape stripping and which dermatoses have been studied by tape stripping.
Evidence regarding different protocols for protein and RNA extraction from tape strips is reviewed.
Maximal RNA yield is obtained from 20 tape strips using a cell scraper.
Summary
Background
Linear morphoea (LM) is a rare connective tissue disorder characterized by a line of thickened skin and subcutaneous tissue and can also affect the underlying muscle and bone. ...Little is known about the disease aetiology, with treatment currently limited to immune suppression, and disease recurrence post‐treatment is common.
Objectives
In order to uncover new therapeutic avenues, the cell‐intrinsic changes in LM fibroblasts compared with site‐matched controls were characterized.
Methods
We grew fibroblasts from site‐matched affected and unaffected regions from five patients with LM, we subjected them to gene expression analysis and investigation of SMAD signalling.
Results
Fibroblasts from LM lesions showed increased migration, proliferation, altered collagen processing, and abnormally high basal levels of phosphorylated SMAD2, thereby rendering them less responsive to transforming growth factor (TGF)‐β1 and reducing the degree of myofibroblast differentiation, which is a key component of the wound‐healing and scarring process in normal skin. Conditioned media from normal fibroblasts could reverse LM‐affected fibroblast migration and proliferation, suggesting that the LM phenotype is driven by an altered secretome. Gene array analysis and RNA‐Seq indicated upregulation of ADAMTS8 and downregulation of FRAS1 and SOSTDC1. SOSTDC1 knock‐down recapitulated the reduced TGF‐β1 responsiveness and LM fibroblast migration, while overexpression of ADAMTS8 induced myofibroblast markers.
Conclusions
We demonstrate that cell‐intrinsic changes in the LM fibroblast secretome lead to changes observed in the disease, and that secretome modulation could be a viable therapeutic approach in the treatment of LM.
What's already known about this topic?
Linear morphoea (LM) is a rare connective tissue disorder.
The underlying mechanism responsible for the fibrosis of LM is unknown.
What does this study add?
LM fibroblasts from diseased skin possess a persistent identifiable cell phenotype.
LM fibroblasts display increased cell growth and migration, and reduced response to transforming growth factor‐β1.
What is the translational message?
Cell‐intrinsic changes in the LM fibroblast secretome lead to changes observed in the disease.
Secretome modulation could be a viable therapeutic approach in the treatment of LM.
Linked Comment: Mellody et al. Br J Dermatol 2019; 180:985–987.
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