A crosstalk between intracellular CXCR7 and CXCR4 involved in rapid CXCL12‐triggered integrin activation but not in chemokine‐triggered motility of human T lymphocytes and CD34+ cells

@article{Hartmann2008ACB,
  title={A crosstalk between intracellular CXCR7 and CXCR4 involved in rapid CXCL12‐triggered integrin activation but not in chemokine‐triggered motility of human T lymphocytes and CD34+ cells},
  author={Tanja Nicole Hartmann and V. M. Grabovsky Grabovsky and Ronit Pasvolsky and Ziv Shulman and Eike C. Buss and Asaf Spiegel and Arnon Nagler and Tsvee Lapidot and Marcus Thelen and Ronen Alon},
  journal={Journal of Leukocyte Biology},
  year={2008},
  volume={84}
}
The chemokine CXCL12 promotes migration of human leukocytes, hematopoietic progenitors, and tumor cells. The binding of CXCL12 to its receptor CXCR4 triggers Gi protein signals for motility and integrin activation in many cell types. CXCR7 is a second, recently identified receptor for CXCL12, but its role as an intrinsic G‐protein‐coupled receptor (GPCR) has been debated. We report that CXCR7 fails to support on its own any CXCL12‐triggered integrin activation or motility in human T lymphocytes… 
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