SULFUR MUSTARD-INDUCED RESPONSES OF AIRWAY AND SKIN IN VITRO.

Sulfur mustard (SM) is a vesicant that has been used in warfare and is a potential threat to civilians either from acts of terrorism or through accidental exposure to abandoned military caches of the chemical. Exposure of the skin produces blisters and slow-healing wounds resulting in scarring, while exposure of the lung causes short-term sloughing of the epithelium and longer term fibrotic responses. Inflammatory responses are also involved. Currently, few useful therapeutic agents are available to ameliorate the adverse reactions to this agent. In vitro models of human tissues could provide faster and more cost-effective screening prior to definitive testing in an animal model. As preliminary model development, we exposed human full thickness models of the skin and airway epithelium (EpiDerm and EpiAirway cultures; MatTek Corp.) to SM vapor or to air. Half of the cultures were then transferred to the appropriate medium and the others were transferred to medium containing approximately 10 million freshly isolated human peripheral blood leukocytes. The cultures were returned to the incubator. After 24 h, the medium was harvested for analysis of matrix metalloproteinase (MMP) activity and cytokines. The cell layers were cut into two parts: one was fixed for histopathology and the other was frozen in lysis buffer. Epithelial sloughing (airway) and microblister formation (dermal) was observed in the SM-exposed cultures. The results showed upregulation of several key cytokines, with some modulation of the responses in cultures with leukocytes during the post-exposure incubations. In many cases, the responses closely mirrored responses in the lungs of rats exposed to SM vapors. MMP activity was increased in the medium as well as the cell lysates of the dermal model. These results provide preliminary information for further development of a relevant model for testing potential therapeutics.

AFT-100, EFT-400, EpiAirway, EpiDerm-FT, Guinea pigs, Histological assessment, Human peripheral leukocytes, IL-10, IL-17, IL-4, IL-8, Matrix metalloproteinase (MMP), MMP-2, MMP-9, Rats, Sulfur mustard, Th17, Th2, TNF-α, Vesicant

Leukocytes, Sulfur mustard (SM)