Rho family small GTPases control migration of hematopoietic progenitor cells into multicellular spheroids of bone marrow stroma cells.
J Leukoc Biol
; 72(4): 837-45, 2002 Oct.
Article
em En
| MEDLINE
| ID: mdl-12377954
ABSTRACT
Seeding of hematopoietic progenitor cells (HPC) into the bone marrow requires a complex interaction between cell membrane and adhesion systems and cell signaling pathways. We established a multicellular, spheroid coculture model to study HPC migration in a three-dimensional stromal environment. Here, entry of primary CD34(+) cells into stroma cell spheroids was independent of the integrins very late antigen (VLA)-4, VLA-5, lymphocyte function-associated antigen-1, and the chemokine receptor CXCR4. Experiments using a panel of bacterial toxins selectively targeting key regulators of cellular locomotion, the Rho family small GTPases Rho, Rac, and Cdc42, revealed a considerable reduction or even abrogation of TF-1 cell migration without an increase of apoptosis or impairment of proliferation. Pertussis toxin, an inhibitor of Galpha(i) proteins, showed a similar effect. In some in vitro invasion assays, phosphatidylinositol-3 kinase (PI-3K) was shown to mediate Rac- and Cdc42-induced cell motility and invasion. However, inhibition of the PI-3K pathway by LY294002 did not impair TF-1 cell migration in our three-dimensional model system.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Bactérias
/
Células-Tronco Hematopoéticas
/
Movimento Celular
/
Proteínas rho de Ligação ao GTP
/
Proteína cdc42 de Ligação ao GTP
/
Proteínas rac de Ligação ao GTP
Tipo de estudo:
Prognostic_studies
Limite:
Humans
Idioma:
En
Ano de publicação:
2002
Tipo de documento:
Article