Expression and a role of functionally coupled P2Y receptors in human dendritic cells

FEBS Letters

Christensen, O.¹  Fleischmann, B.K.²  Bohlen, H.¹  Titzer, S.¹  Hescheler, J.²  Diehl, V.¹  Liu, Q.H.² 

[1] Department of Internal Medicine I, University of Cologne, Robert-Koch-Str. 39, D-50931 Cologne, Germany;Institute of Neurophysiology, University of Cologne, Robert-Koch-Str. 39, D-50931 Cologne, Germany

关键词: Human dendritic cell;    P2Y receptor;    Non-selective cation current;    Chemokine;   

DOI  :  10.1016/S0014-5793(99)00161-1

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

We investigated the physiology and function of P2Y receptors expressed in human dendritic cells (DCs) differentiated in vitro from CD14⁺ cells (DC-14). These were obtained after a 10 day stimulation period in GM-CSF, IL-4 and monocyte conditioned medium. DC-14 were found to express high amounts of MHC class II, B7, CD40 as well as CD83. The functional analysis, using single cell Ca²⁺ imaging, demonstrated the expression of at least three subtypes of P2Y receptors. We further found using patch-clamp measurements that ATP evoked a pertussis toxin insensitive non-selective cation current with a peak current amplitude of −276±43 pA (holding potential −80 mV, n=23). This current was not Ca²⁺-activated, since it was still observed under conditions of high intracellular Ca²⁺ buffering and could be blocked by Gd³⁺ (0.5 mM). In addition, intracellular application of GTP-γ-S (0.3 mM) also activated the current. Interestingly, DC-14 redirected the orientation of their dendrites as well as cell shape towards a pipette containing ATP as observed with time lapse microscopy. These data suggest that in human DCs, ATP acts via P2Y receptors and induces chemokine effects.

【 授权许可】

Unknown