Chemokine receptor CXCR4 signaling modulates the growth factor-induced cell cycle of self-renewing and multipotent neural progenitor cells.
CXC chemokine receptor CXCR4 is expressed in vitro in both human and rodent adult neural progenitor cells (NPCs). It has been suggested that the CXCL12-CXCR4 axis potentially enhances the proliferation of NPCs. However, whether CXCR4 is expressed in the neural stem cells (NSCs), a subset of self-renewing and multipotent NPCs, and whether CXCR4 signaling is directly required for their proliferation are not clear. In this study, we report that CXCR4 is expressed in a subpopulation of NPCs in the early embryonic ventricular zone. In studies of a CXCR4(eGFP) bacterial artificial chromosomal (BAC) transgenic mouse line, we further isolated NPCs from E12.5 transgenic telencephalon and GFP(+) cells demonstrated self-renewal and multipotency in neurosphere assays in vitro. Consistent with these observations, we enriched GFP(+)/CXCR4(+) cells by fluorescence activated cell sorting (FACS) with either CXCR4 antibody 12G5 or GFP. Furthermore, we observed that CXCL12 alone did not activate the self-renewal of NPCs or increase the proliferation of NPCs that are induced by bFGF/EGF. However, we found that blocking CXCR4 receptor with antagonist AMD3100 impaired the bFGF/EGF-induced expansion of GFP(+) NPCs through modulating their cell cycling. In addition, AMD3100 treatment of pregnant mice reduced the generation of neurospheres from E12.5 embryos. Our data suggest that CXCR4 is a potential cell surface marker for early embryonic NSCs and modulates growth-factor signaling.
Department of Neuroscience, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio 44195, USA.
Meizhang
M
Li
Cathleen J
CJ
Chang
Justin D
JD
Lathia
Li
L
Wang
Holly L
HL
Pacenta
Anne
A
Cotleur
Richard M
RM
Ransohoff
D000704:Analysis of Variance; D000818:Animals; D002453:Cell Cycle / Q000187:drug effects / Q000502:physiology*; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D004797:Enzyme-Linked Immunosorbent Assay; D004815:Epidermal Growth Factor / Q000494:pharmacology; D016222:Fibroblast Growth Factor 2 / Q000494:pharmacology; D005434:Flow Cytometry; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D051379:Mice; D008822:Mice, Transgenic; D039902:Multipotent Stem Cells / Q000187:drug effects / Q000378:metabolism*; D058953:Neural Stem Cells / Q000187:drug effects / Q000378:metabolism*; D016548:Prosencephalon / Q000166:cytology / Q000378:metabolism; D019718:Receptors, CXCR4 / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology*
C514936:CXCR4 protein, mouse; D019718:Receptors, CXCR4; D016222:Fibroblast Growth Factor 2; D004815:Epidermal Growth Factor