Recent studies from our laboratory have shown that substance P can elicit transcription factor activation in dendritic cells. In the present study, we extend these findings by demonstrating the presence of authentic substance P (NK-1) receptors on both normal murine and human dendritic cells. Specifically, we demonstrate the presence of mRNA encoding NK-1 tachykinin receptors and have utilized specific antibodies to detect the expression of NK-1 receptor protein in dendritic cells by Western blot analysis and flaw cytometry. These data provide a crucial first step in determining the potential of substance P to modulate dendritic cell function. (C) 2001 Elsevier Science BN. All rights reserved.