Effect of azathioprine on Na(+)/H(+) exchanger activity in dendritic cells

Cell Physiol Biochem. 2012;29(3-4):533-42. doi: 10.1159/000338507. Epub 2012 Apr 3.


Azathioprine is a powerful immunosuppressive drug, which is partially effective by interfering with the maturation and function of dendritic cells (DCs), antigen-presenting cells linking innate and adaptive immunity. DCs are stimulated by bacterial lipopolysaccharides (LPS), which trigger the formation of reactive oxygen species (ROS), paralleled by activation of the Na(+)/H(+) exchanger. The carrier is involved in the regulation of cytosolic pH, cell volume and migration. The present study explored whether azathioprine influences Na(+)/H(+) exchanger activity in DCs. DCs were isolated from murine bone marrow, cytosolic pH (pH(i)) was estimated utilizing 2',7'-bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein (BCECF-AM) fluorescence, Na(+)/H(+) exchanger activity from the Na(+)-dependent realkalinization following an ammonium pulse, cell volume from forward scatter in FACS analysis, ROS production from 2',7'-dichlorodihydrofluorescein diacetate (DCFDA) fluorescence, TNFα release utilizing ELISA, and migration utilizing transwell migration assays. Exposure of DCs to lipopolysaccharide (LPS, 1 μg/ml) led to a transient increase of Na(+)/H(+) exchanger activity, an effect paralleled by ROS formation, increased cell volume, TNFα production and stimulated migration. Azathioprine (10 μM) did not significantly alter the Na(+)/H(+) exchanger activity, cell volume and ROS formation prior to LPS exposure but significantly blunted the LPS-induced stimulation of Na(+)/H(+) exchanger activity, ROS formation, cell swelling, TNFα production and cell migration. In conclusion, azathioprine interferes with the activation of dendritic cell Na(+)/H(+) exchanger by bacterial lipopolysaccharides, an effect likely participating in the anti-inflammatory action of the drug.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Azathioprine / pharmacology*
  • Cell Movement
  • Cell Size
  • Cells, Cultured
  • Cytosol / metabolism
  • Dendritic Cells / drug effects*
  • Dendritic Cells / metabolism
  • Dendritic Cells / physiology
  • Enzyme-Linked Immunosorbent Assay
  • Female
  • Flow Cytometry
  • Fluoresceins / metabolism
  • Fluorescence
  • Hydrogen-Ion Concentration
  • Lipopolysaccharides / pharmacology
  • Mice
  • Mice, Inbred C57BL
  • Reactive Oxygen Species / metabolism
  • Sodium-Hydrogen Exchangers / drug effects*
  • Sodium-Hydrogen Exchangers / metabolism
  • Sodium-Hydrogen Exchangers / physiology
  • Tumor Necrosis Factor-alpha / metabolism


  • Fluoresceins
  • Lipopolysaccharides
  • Reactive Oxygen Species
  • Sodium-Hydrogen Exchangers
  • Tumor Necrosis Factor-alpha
  • diacetyldichlorofluorescein
  • 2',7'-bis(carboxyethyl)-5(6)-carboxyfluorescein
  • Azathioprine