Increased coexpression of eotaxin and interleukin 5 in bullous pemphigoid

While the presence of eosinophils in the skin lesions of bullous pemphigoid is well documented, the chemotactic factors responsible for eosinophil recruitment into the tissue still remain to be defined. In this study, eotaxin and interleukin-5 (IL-5) concentrations were determined in the blister fluid and sera of patients with bullous pemphigoid (acute and remission phase, n=6) in comparison with normal healthy controls (n=6) using the enzyme-linked immunosorbent assay (ELISA) technique. Eotaxin and IL-5 levels were increased in the blister fluid compared with the acute and remission phase sera, as well as compared with the sera of normal controls. In addition, immunoreactivity for eotaxin was predominantly found in the inflammatory cell infiltrate of lesional bullous pemphigoid biopsy specimens. In conclusion, the data provide evidence that co-operation of eotaxin and IL-5 may play an essential role in activating and recruiting eosinophils, which ultimately contribute to the tissue damage in bullous pemphigoid.