Platelet activating factor-induced clinical and histopathologic responses in atopic skin and their modification by...

The clinical and histopathologic responses to intradermal platelet-activating factor (PAF-acether) in atopic subjects, without evidence of atopic dermatitis are documented. An immediate acute wheal and flare reaction was observed in all volunteers. Histopathologically, the reaction was characterized by a predominantly neutrophilic response, which was seen at 30 minutes and was maximal at 4 hours. Eosinophils were observed in the infiltrate as early as 30 minutes after injection, and were maximal by 12 hours. The specific PAF-acether antagonist BN52063 antagonized the acute flare response to intradermal PAF-acether but had little effect on cellular recruitment at the site of injection.