Induction of delayed-type hypersensitivity responses to PPD: dendritic cells in synergy with 5-hydroxytryptamine can substitute for macrophages.
We describe the use of 5-hydroxytryptamine (5HT) as an adjuvant in the induction of the delayed-type hypersensitivity (DTH) response to purified protein derivative (PPD). Based upon our previous studies with antigen-pulsed macrophages (M phi), we have shown that both the Day 2 early (2 hr) reaction and the Day 3 (24 hr) reaction are augmented if 5HT is incorporated into the priming injection. Furthermore, we have confirmed that in contrast to M phi, antigen-pulsed dendritic cells (DC) fail to prime the early (2 hr) component of DTH. However, DC do prime the early response if injected along with 5HT. A peripheral 5HT antagonist, ICS 205-930, inhibits both the M phi-mediated and the 5HT/DC-primed reactions. These findings support the hypothesis that DTH reactions require a cascade of both inflammatory and immunological signals, and that in mice vascular permeability mediated via 5HT is important in the early phase of the reaction.
Roberts
D
D
Bland Sutton Institute of Pathology, University College and Middlesex School of Medicine, London, U.K.
Katz
D R
DR
Mukherjee
S
S
Rook
G A
GA
D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D000818:Animals; D003713:Dendritic Cells / Q000276:immunology*; D005260:Female; D006968:Hypersensitivity, Delayed / Q000276:immunology*; D008264:Macrophages / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D012701:Serotonin / Q000276:immunology*; D012702:Serotonin Antagonists / Q000494:pharmacology; D014373:Tuberculin / Q000276:immunology*
D000276:Adjuvants, Immunologic; D012702:Serotonin Antagonists; D014373:Tuberculin; D012701:Serotonin