A non-invasive tape absorption method for recovery of inflammatory mediators to differentiate normal from compromised scalp conditions.

BACKGROUND/AIMS: A simple non-invasive tape (Sebutape) adsorption method was used to recover inflammatory proteins from normal and compromised human scalp (i.e. dandruff and seborrheic dermatitis) in order to assess the inflammatory and immunologic changes relevant to these clinical conditions. METHODS: The scalps of subjects identified by a dermatologist as having either dandruff (n = 18), seborrheic dermatitis (n = 19) or normal scalp (n = 16) were visually graded to obtain total adherent scalp flaking scores (TASFS). Sebutape samples were then collected from both the high and low TASFS scalp sites using a one-minute tape application. To recover inflammatory molecules, tapes were extracted in buffered saline with sonication and the tape extracts analysed using commercial immunoassay methods for pro-inflammatory cytokines [i.e. interleukin-1alpha (IL-1alpha), IL-1beta, IL-1 receptor antagonist (IL-1ra), IL-8 and tumor necrosis factor-alpha (TNF-alpha)] and the immunologic cytokines [i.e. IL-2, IL-4, IL-10, IL-12, IL-15 and interferon gamma (IFN-gamma)]. Nitric oxide (NO) was also assayed on tape extracts using the Greiss reaction. To account for differences in protein loading on the tapes all cytokine and NO results were normalized using the total protein (TP) amounts recovered in tape extracts. RESULTS: The IL-1alpha/TP levels recovered from dandruff and seborrheic scalps were significantly decreased (P = 0.03) compared to normal appearing scalp levels. The scalp levels of IL-1ra/TP and the ratio of IL-ra to IL-1alpha were significantly (P = 0.002) or directionally (P = 0.07) higher in seborrheic dermatitis scalps and dandruff scalps, respectively, compared to normal scalps. The IL-1ra and the IL-1ra/IL-1alpha ratio values correlated well with the TASFS. The TNF-alpha/TP levels recovered from dandruff scalps were significantly higher (P = 0.02) than levels recovered from seborrheic dermatitis and normal scalp subjects. IL-2/TP was significantly increased (P = 0.01) and IFN-gamma and NO significantly decreased (P = 0.05) in the seborrheic dermatitis scalp samples compared to normal controls. CONCLUSION: The Sebutape method has proven useful for distinguishing normal from diseased scalp conditions. The cytokines recovered from the scalp tape samples showed distinct patterns that differentiated dandruff, seborrheic dermatitis and normal scalp populations. These methods may also prove useful for monitoring the clinical efficacy of therapeutic actives for treating dandruff and seborrhea.

A noninvasive method to assess skin irritation and compromised skin conditions using simple tape adsorption of molecular markers of inflammation.

BACKGROUND/AIMS: We have developed a simple noninvasive method to assess inflammatory changes in human skin, even in the absence of visible clinical irritation. Our approach is based on a simple tape (Sebutape) adsorption method to recover molecular mediators of skin inflammation (e.g., cytokines). This procedure has been used to investigate baseline cytokine levels on skin, to assess normal skin condition and to evaluate changes due to chemical insult, existing dermatitis, or sun exposure. METHODS: In clinical studies, Sebutape was applied to normal appearing uncompromised skin, as well as to compromised (diaper or heat rash), chemically treated (sodium laurel sulfate), or sun-exposed skin. Sebutape was applied to the skin for a 1 min collection interval. Tapes were extracted in saline using a 10 min sonication, and the extracts were analyzed for human interleukin-1alpha (IL-1alpha), IL-1 receptor antagonist (IL-1RA) and IL-8 using commercial immunoassay test kits. The cytokine levels recovered from each tape extract were normalized to total protein (TP) levels. In infant product use tests, the severity of skin irritation (diaper and heat rash or erythema) was also assessed using a visual grading scale. RESULTS: The method itself caused minimal, if any, skin damage. Additionally, Sebutape was shown to quantitatively adsorb detectable levels of cytokine from normal-appearing (control) or compromised (e.g., rashed or chemically treated) skin. In infant studies, significant increases in IL-1alpha levels were found in skin exhibiting diaper rash, heat rash and erythema compared with normal appearing control skin sites. When these results were normalized to total protein levels recovered from each tape, the significance was maintained. A positive correlation (r2=0.82) existed between IL-1RA levels and diaper rash severity. Significant increases in IL-8 levels were recovered from diaper rash versus control skin sites. There were differences in baseline cytokine levels in normal skin related to body site and sun exposure. The IL-1 RA/IL-1alpha ratios for sun-exposed skin of the face and lower leg were significantly (P<0.05) higher (3-6-fold) than those for skin sites that typically receive minimal sun exposure (i.e., underarm, upper leg and upper back). There was a significant increase in IL-1alpha and a directional increase in IL-8 levels in adult skin sites treated with the irritant, sodium lauryl sulfate, even in the absence of visible skin irritation (erythema). CONCLUSION: Our results demonstrate that this method is a useful noninvasive technique for assessing skin inflammatory events. In addition, the method is simple and easily applied in a clinical setting, whether on infants or adults.