Multiphoton imaging the disruptive nature of sulfur mustard lesions

Abstract

Sulfur mustard [bis-2-chloroethyl sulfide] is a vesicating agent first used as a weapon of war in WWI. It causes debilitating blisters at the epidermal-dermal junction and involves molecules that are also disrupted by junctional epidermolysis bullosa (JEB) and other blistering skin diseases. Despite its recurring use in global conflicts, there is still no completely effective treatment. We have shown by imaging human keratinocytes in cell culture and in intact epidermal tissues that the basal cells of skin contain well-organized molecules (keratins K5/K14, 6 4 integrin, laminin 5 and 3 1 integrin) that are early targets of sulfur mustard. Disruption and collapse of these molecules is coincident with nuclear displacement, loss of functional asymmetry, and loss of polarized mobility. The progression of this pathology precedes basal cell detachment by 8-24 h, a time equivalent to the "clinical latent phase" that defines the extant period between agent exposure and vesication. Our images indicate that disruption of adhesion-complex molecules also impairs cytoskeletal proteins and the integration of structures required for signal transduction and tissue repair. We have recently developed an optical system to test this hypothesis, i.e., to determine whether and how the early disruption of target molecules alters signal transduction. This environmentally controlled on-line system provides a nexus for realtime correlation of imaged lesions with DNA microarray analysis, and for using multiphoton microscopy to facilitate development of more effective treatment strategies.

Microarray Analysis of Mouse Ear Tissue Exposed to Bis-(2-chloroethyl) Sulfide: Gene Expression Profiles Correlate with Treatment Efficacy and An Established Clinical Endpoint

“…K5/K14 are associated with proliferating cells in the basal layer of the epidermis, whereas K1/K10 are associated with terminally differentiating cells in the suprabasal layers of the epidermis. SM exposure also results in perturbation of the actin cytoskeleton (Werrlein et al, 2005). Our data regarding altered gene expression are in agreement with these observations that cytoskeletal proteins are adversely affected by SM exposure.…”

Direct binding of sulfur mustard and chloroethyl ethyl sulphide to human cell membrane-associated proteins; implications for sulfur mustard pathology

“…There has been little research into the effect of SM on actin in the cell. Werrlein et al showed a collapse of the actin cytoskeleton in the cell on exposure to SM [27]. Dabrowska et al showed that disruption of the long actin filament stress fibres and rounding of cells preceded other features of apoptosis, and noticed an increase in the amount of actin monomer compared to filaments [28] and recently Mol et al showed that SM bound to actin in human keratinocyte cells [9].…”

The use of doxycycline as a protectant against sulphur mustard in HaCaT cells

“…Later work by Werrlein et al (2005) indicated that laminin 5 and other molecules such as keratin K5 and K14, and the integrins (α 3 β 1 and α 6 β 4 ) were early targets of HD in human keratinocyte cultures. Disruption of these targets precedes the detachment of basal cells.…”

“…Laminin, one of the most important molecules which mediate attachment of the basal epidermal layer to the underlying basement membrane (Abrahamson, 1986;Katz, 1984), has been found to undergo degradation in Yucatan mini pig skin following topical exposure to HD (Lindsay and Rice, 1995). Later work by Werrlein et al (2005) indicated that laminin 5 and other molecules such as keratin K5 and K14, and the integrins (α 3 β 1 and α 6 β 4 ) were early targets of HD in human keratinocyte cultures. Disruption of these targets precedes the detachment of basal cells.…”