Evidence for LTB4/12-HETE binding sites in a human epidermal cell line.
We identified leukotriene B4 (LTB4)/12-hydroxyeicosatetraenoic acid (12-HETE) binding sites in a squamous cell cancer-derived human epidermal cell line. Analysis of the binding data revealed a single class of binding sites with a dissociation constant of 0.16 microM and a Bmax of 3.8 x 10(6) sites per cell. Competitive binding assays with various eicosanoids at 37 degrees C showed nearly equal binding of 12(S)-HETE, 12(R)-HETE and LTB4. 5(S)-HETE and LTB4-analogs bound with lesser affinity. Specific LTB4 binding at 37 degrees C could also be demonstrated in freshly isolated normal human keratinocytes. Since lipoxygenase-derived eicosanoids are thought to play an important role in hyperproliferative and inflammatory skin diseases, the identification of LTB4/12-HETE binding sites in keratinocytes could have implications for the development of new drugs controlling these disease processes.
Gross
E
E
Department of Dermatology, University of Munich, FRG.
Ruzicka
T
T
Mauch
C
C
Krieg
T
T
D019377:12-Hydroxy-5,8,10,14-eicosatetraenoic Acid; D001665:Binding Sites; D001667:Binding, Competitive; D002294:Carcinoma, Squamous Cell / Q000378:metabolism; D002460:Cell Line; D004817:Epidermis / Q000378:metabolism*; D006801:Humans; D006893:Hydroxyeicosatetraenoic Acids / Q000378:metabolism*; D007536:Isomerism; D007975:Leukotriene B4 / Q000378:metabolism*
D006893:Hydroxyeicosatetraenoic Acids; D007975:Leukotriene B4; D019377:12-Hydroxy-5,8,10,14-eicosatetraenoic Acid