The University of Southampton
University of Southampton Institutional Repository

Effects of irritants in the epidermis: the role of kallikrein 5 and 7 and protease activated receptor 2

Effects of irritants in the epidermis: the role of kallikrein 5 and 7 and protease activated receptor 2
Effects of irritants in the epidermis: the role of kallikrein 5 and 7 and protease activated receptor 2
Contact dermatitis affects 0.5-1.9 cases per 1,000 full-time workers annually, with 80% of cases accounted for by irritant contact dermatitis. The mechanisms underlying irritant contact dermatitis are incompletely understood and there is also a large need in industry for screening tools to identify the irritant potential of novel chemical compounds. The aim of this thesis was to investigate whether disruption of the stratum corneum barrier by irritants induces epidermal serine proteases such as KLKs which act through the PAR2 receptor to cause a pro-inflammatory response. Croton oil (3%) and SDS (5%) were applied to ex vivo human skin and expression of KLK5, KLK7 and PAR2 analysed. Both croton oil and SDS increased KLK5 (p=0.0001 and 0.0002 respectively), KLK7 (p=0.0027 and 0.0009 respectively), and PAR2 (p=0.0057 and p=0.0215 respectively). In addition, protease activity within the epidermis was concomitantly increased (p=0.0094 for croton oil and p=0.0185 for SDS).

Although these findings help to provide mechanistic insight, and could have some use as a screening tool, the availability of human skin is a limiting factor in an industrial setting. Using Rho kinase-inhibition to increase the proliferative capacity of adult human keratinocytes to generate 3D epidermal equivalents, it was noted that the resulting stratum corneum was insufficiently resilient to withstand application of SDS, even at reduced concentrations. However, in monolayer cultures it was noted that, following initial screening using qPCR arrays, croton oil and dithranol caused upregulation of IL6, IL36A, CCL5 and CSF2 in Rho kinase-inhibited keratinocytes, and that CCL5 and CSF2 were similarly upregulated in normal human keratinocytes exposed to these compounds. Thus, in Rho kinase-inhibited keratinocytes, CCL5 and CSF2 (and possibly IL6 and IL36A) may form a useful screening tool for potential irritants generated in industry, although further work will be required to test sensitivity and specificity of this approach.
University of Southampton
Underwood, Joanne
7f90e572-decb-4c0e-9de9-02c2b346dbbe
Underwood, Joanne
7f90e572-decb-4c0e-9de9-02c2b346dbbe
Healy, Eugene
400fc04d-f81a-474a-ae25-7ff894be0ebd
Friedmann, Peter
d50bac23-f3ec-4493-8fa0-fa126cbeba88

Underwood, Joanne (2013) Effects of irritants in the epidermis: the role of kallikrein 5 and 7 and protease activated receptor 2. University of Southampton, Doctoral Thesis, 260pp.

Record type: Thesis (Doctoral)

Abstract

Contact dermatitis affects 0.5-1.9 cases per 1,000 full-time workers annually, with 80% of cases accounted for by irritant contact dermatitis. The mechanisms underlying irritant contact dermatitis are incompletely understood and there is also a large need in industry for screening tools to identify the irritant potential of novel chemical compounds. The aim of this thesis was to investigate whether disruption of the stratum corneum barrier by irritants induces epidermal serine proteases such as KLKs which act through the PAR2 receptor to cause a pro-inflammatory response. Croton oil (3%) and SDS (5%) were applied to ex vivo human skin and expression of KLK5, KLK7 and PAR2 analysed. Both croton oil and SDS increased KLK5 (p=0.0001 and 0.0002 respectively), KLK7 (p=0.0027 and 0.0009 respectively), and PAR2 (p=0.0057 and p=0.0215 respectively). In addition, protease activity within the epidermis was concomitantly increased (p=0.0094 for croton oil and p=0.0185 for SDS).

Although these findings help to provide mechanistic insight, and could have some use as a screening tool, the availability of human skin is a limiting factor in an industrial setting. Using Rho kinase-inhibition to increase the proliferative capacity of adult human keratinocytes to generate 3D epidermal equivalents, it was noted that the resulting stratum corneum was insufficiently resilient to withstand application of SDS, even at reduced concentrations. However, in monolayer cultures it was noted that, following initial screening using qPCR arrays, croton oil and dithranol caused upregulation of IL6, IL36A, CCL5 and CSF2 in Rho kinase-inhibited keratinocytes, and that CCL5 and CSF2 were similarly upregulated in normal human keratinocytes exposed to these compounds. Thus, in Rho kinase-inhibited keratinocytes, CCL5 and CSF2 (and possibly IL6 and IL36A) may form a useful screening tool for potential irritants generated in industry, although further work will be required to test sensitivity and specificity of this approach.

Text
J Underwood PhD Thesis - Version of Record
Available under License University of Southampton Thesis Licence.
Download (7MB)

More information

Published date: September 2013
Organisations: University of Southampton, Clinical & Experimental Sciences

Identifiers

Local EPrints ID: 408107
URI: https://eprints.soton.ac.uk/id/eprint/408107
PURE UUID: 20892ccc-af65-4b77-a79b-e0a374c403f4

Catalogue record

Date deposited: 12 May 2017 04:03
Last modified: 13 Mar 2019 19:56

Export record

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of https://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×