Erika Bornscheuer

Immunohistochemical studies on NAP-1/IL-8 in contact eczema and atopic dermatitis

SummaryThe neutrophil activating peptide NAP-1/IL-8 has in the past been shown to be secreted by diverse cell-types involved in inflammatory processes. Furthermore, potent biological effects on both neutrophilic granulocytes and lymphocytes enforce its role in inflammation. Recently, immunohistochemical studies using monoclonal anti-NAP-1/IL-8 antibodies have been performed on dermal inflammatory conditions like psoriasis vulgaris. These have demonstrated epidermal IL-8 immunoreactivity in a pattern inversely related to the degree of inflammatory infiltration. Based on these results, in the present study biopsies from patients with contact eczema as well as atopic dermatitis were examined. The same patterns of immunoreactivity were found with either homogenous epidermal staining, focally negative staining or overall decreased or even absent staining. As in psoriasis, these patterns were related to the degree of inflammatory infiltration. These results prove NAP-1/IL-8 to be involved not only in psoriasis vulgaris, but more likely to be a marker of different inflammatory processes. Future work will have to examine the kinetics as well as stimuli causing these effect.

Lack of expression of interleukin 8 and RANTES in autoimmune bullous skin diseases.

Background: In autoimmune bullous skin diseases, accumulation of neutrophils and/or eosinophils in the affected skin represents a characteristic feature. So far, however, the induction of this granulocyte infiltration has not been elucidated. Objective: Regarding their biological effects, the chemokines interleukin 8 (IL-8) and RANTES (regulated upon activation normal T lymphocyte expressed and secreted) could play a role in this granulocyte accumulation. Methods: Immunohistochemical examination of lesional skin from patients with bullous pemphigoid, pemphigus, dermatitis herpetiformis and linear IgA disease was performed using a set of different antibodies against IL-8 and RANTES. Additionally, blister fluids were screened for soluble RANTES peptide using an ELISA. Results: No difference in chemokine expression was found in lesions of autoimmune bullous diseases compared to normal skin. Conclusion: In contrast to chronic inflammatory diseases like psoriasis and eczema, where keratinocyte IL-8 immunoreactivity was found to differ from normal skin, keratinocyte immunoreactivity is not altered in autoimmune bullous diseases.

Neutrophil-Activating Peptide 1/Interleukin 8

In recent years different cytokines have been claimed to play a role in initiation and perpetuation of the eczematous tissue reaction. Among these factors is the neutrophil activating peptide 1/interleukin-8 (NAP-1/IL-8) [1]. This 72 amino acid peptide and variants thereof are produced by a number of different cell types, e.g., monocytes, endothelial cells [2], and fibroblasts [3]. Apart from its main target cell, the neutrophil, NAP-l/IL-8 was also shown to exert chemotactic activity on lymphocytes [4]. As numerical and functional changes have been observed with these cells in eczema IL-8 may well play a role in this disease entity.