Abstract
Pertussigen, a purified protein from Bordetella pertussis, was shown to increase delayed-type hypersensitivity (DTH) to protein antigens in mice. First, it caused an .apprx. 2-fold enhancement of the magnitude of 24 h DTH reactions. Second, the peak magnitude of DTH was delayed to 4-7 days after challenge, at which time it was 5 times more intense than in mice not receiving petussigen. This reaction was antigen specific, and histologically was characterized by a dense mononuclear infiltrate. Third, pertussigen prolonged DTH so that it was still detectable 3-6 wk after challenge. The effect of pertussigen was seen only in antigen-driven reactions and was time and dose depedent, with 400 ng given 3 days after immunization resulting in the most prolonged reaction. The administration of pertussigen to the recipients of sensitized lymph node cells resulted in DTH that was more intense and prolonged than the reactions in control mice. Administration of pertussigen provides a model of prolonged and enhanced T cell-dependent inflammatory responses.