CXCL12 secretion by bone marrow stromal cells is dependent on cell contact and mediated by connexin-43 and connexin-45 gap junctions.
Nat Immunol
; 12(5): 391-8, 2011 May.
Article
em En
| MEDLINE
| ID: mdl-21441933
ABSTRACT
The chemokine CXCL12 is essential for the function of hematopoietic stem and progenitor cells. Here we report that secretion of functional CXCL12 from human bone marrow stromal cells (BMSCs) was a cell contact-dependent event mediated by connexin-43 (Cx43) and Cx45 gap junctions. Inhibition of connexin gap junctions impaired the secretion of CXCL12 and homing of leukocytes to mouse bone marrow. Purified human CD34(+) progenitor cells did not adhere to noncontacting BMSCs, which led to a much smaller pool of immature cells. Calcium conduction activated signaling by cAMP-protein kinase A (PKA) and induced CXCL12 secretion mediated by the GTPase RalA. Cx43 and Cx45 additionally controlled Cxcl12 transcription by regulating the nuclear localization of the transcription factor Sp1. We suggest that BMSCs form a dynamic syncytium via connexin gap junctions that regulates CXC12 secretion and the homeostasis of hematopoietic stem cells.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Células da Medula Óssea
/
Células-Tronco Hematopoéticas
/
Células Estromais
/
Junções Comunicantes
/
Conexinas
/
Quimiocina CXCL12
/
Células-Tronco Mesenquimais
Limite:
Animals
/
Humans
Idioma:
En
Revista:
Nat Immunol
Assunto da revista:
ALERGIA E IMUNOLOGIA
Ano de publicação:
2011
Tipo de documento:
Article
País de afiliação:
Israel