Perkins, M.A., M.A. Osterhues, S. Vogelpohl, and M.K. Robinson. (2000). A clinical skin sampling approach to assess sensory skin irritation. The Toxicologist 54(1). Abstract # 689.
lactic acid - 0005021-5; capsaicin - 00404-86-4
We have developed a noninvasive Sebutape sampling procedure to adsorb and quantify molecular mediators of skin inflammation. This procedure has been used to distinguish inflamed from normal skin or mucosa, where the inflammation is caused by chemical irritants or existing dermatoses such as diaper dermatitis or gingivitis. Recently, we have applied this methodology to atempt to define quantitative markers for neurosensory skin irritation. Sensory skin irritation refers to the myriad of symptomatic complaints (including itch, sting, and burn) frequently associated with inflammatory skin conditions or skin intolerance to various products. Often, sensory skin irritation occurs in the absence of visual skin reactions. The use of our Sebutape procedure was introduced to provide potential means for quantitative assessment of these responses. Study subjects were first introduced to a clinical assessment scale (the labeled magnitude scale or LMS) used to evaluate chemosensory skin reactions to chemical agents. They were then treated with escalating concentrations of chemical stimuli (lactic acid, capsaicin) on the face or arm. After each treatment, they rated the intensity of the reaction on the LMS scale. Applications continued until a moderate degree of intensity was noted. At different times, Sebutape samples were collected from the treatment sites and frozen until analyzed. The clinical results showed a clear dose response pattern in the LMS to the chemical treatments, with most subjects achieving a moderate intensity of response. The Sebutape samples were extracted in buffer and analyzed (via chemical or immunoassay methods) for recoveries of various neuro- and inflammatory mediators. Precise correlations between incidence and/or severity of sensory skin irritation must await large scale subject evaluation; however, clear indications of elevation or decline in specific mediator recoveries (e.g., interleukin-1alpha, interleukin-1 receptor antagonist, IL-1ra/IL-1alpha ratios, interleukin-8, nitric oxide) have been observed and continue to drive this research effort.