An eosinophil chemotactic factor present in blister fluids of bullous pemphigoid patients.

Tissue eosinophilia is often found in the inflammatory lesions of bullous perphigoid. A study made on naturally occurring eosinophil chemotactic activity in the blister fluids of four bullous pemphigoid patients revealed the existence of this activity in all of them. Sephadex G-25 column chromatography showed that the greater part of this eosinophil chemotactic activity was composed of low molecular substance of which the weight was close to that of vitamin B12 (m.w. 1357). The blister fluids and the sera of these patients contained elevated levels of IgE. An IgE anti-skin basement, membrane antibody was found in two if the four sera, and deposits of IgE were detected along the basement membrane zone of the involved skin in one of the patients. On the basis of these findings, we have reason to believe that an eosinophil chemotactic factor of anaphylaxis (ECF-A) participates in the accumulation of eosinophils in the lesions of bullous pemphigoid.