title: Sulfur mustard induces the formation of keratin aggregates in human epidermal keratinocytes.
abstract: The vesicant sulfur mustard is an alkylating agent that has the capacity to cross-link biological molecules. We are interested in identifying specific proteins that are altered upon sulfur mustard exposure. Keratins are particularly important for the structural integrity of skin, and several genetically inherited blistering diseases have been linked to mutations in keratin 5 and keratin 14. We examined whether sulfur mustard exposure alters keratin biochemistry in cultured human epidermal keratinocytes. Western blotting with specific monoclonal antibodies revealed the formation of stable high-molecular-weight "aggregates" containing keratin 14 and/or keratin 5. These aggregates begin to form within 15 min after sulfur mustard exposure. These aggregates display a complex gel electrophoresis pattern between approximately 100 and approximately 200 kDa. Purification and analysis of these aggregates by one- and two-dimensional gel electrophoresis and mass spectrometry confirmed the presence of keratin 14 and keratin 5 and indicate that at least some of the aggregates are composed of keratin 14-keratin 14, keratin 14-keratin 5, or keratin 5-keratin 5 dimers. These studies demonstrate that sulfur mustard induces keratin aggregation in keratinocytes and support further investigation into the role of keratin aggregation in sulfur mustard-induced vesication.
authors.affiliation: Applied Pharmacology Branch, U.S. Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, MD 21010-5400, USA. James.Dillman@apg.amedd.army.mil
authors.forename: James F
authors.initials: JF
authors.lastname: Dillman
authors.forename: Kriston L
authors.initials: KL
authors.lastname: McGary
authors.forename: John J
authors.initials: JJ
authors.lastname: Schlager
mesh_terms: D015153:Blotting, Western; D002478:Cells, Cultured; D002619:Chemical Warfare Agents / Q000633:toxicity*; D019281:Dimerization; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D006801:Humans; D053547:Keratin-14; D053555:Keratin-5; D015603:Keratinocytes / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D007633:Keratins / Q000032:analysis / Q000187:drug effects* / Q000378:metabolism; D009151:Mustard Gas / Q000633:toxicity*; D010449:Peptide Mapping; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D002619:Chemical Warfare Agents; C507540:KRT14 protein, human; C503940:KRT5 protein, human; D053547:Keratin-14; D053555:Keratin-5; D007633:Keratins; D009151:Mustard Gas