Description:
<jats:p>Stromal cell-derived factor-1alpha (SDF-1<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="E2"><mml:mi>α</mml:mi></mml:math>) has pleiotropic effects on hematopoietic progenitor cells (HPCs). We have monitored podia formation, migration, proliferation, and cell-cell adhesion of human HPC under the influence of SDF-1<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="E3"><mml:mi>α</mml:mi></mml:math>, a peptide agonist of CXCR4 (CTCE-0214), a peptide antagonist (CTCE-9908), and a nonpeptide antagonist (AMD3100). Whereas SDF-1<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="E4"><mml:mi>α</mml:mi></mml:math>induced migration of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="E5"><mml:mrow><mml:mtext>CD</mml:mtext><mml:msup><mml:mrow><mml:mn>34</mml:mn></mml:mrow><mml:mo>+</mml:mo></mml:msup></mml:mrow></mml:math>cells in a dose-dependent manner, CTCE-0214, CTCE-9908, and AMD3100 did not induce chemotaxis in this concentration range albeit the peptides CTCE-0214 and CTCE-9908 increased podia formation. Cell-cell adhesion of HPC to human mesenchymal stromal cells was impaired by the addition of SDF-1<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="E6"><mml:mi>α</mml:mi></mml:math>, CTCE-0214, and AMD3100. Proliferation was not affected by SDF-1<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="E7"><mml:mi>α</mml:mi></mml:math>or its analogs. Surface antigen detection of CXCR4 was reduced upon treatment with SDF-1<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="E8"><mml:mi>α</mml:mi></mml:math>or AMD3100 and it was enhanced by CTCE-9908. Despite the fact that all these molecules target the same CXCR4 receptor, CXCR4 agonists and antagonists have selective effects on different functions of the natural molecule.</jats:p>