CD40 signaling instructs chronic lymphocytic leukemia cells to attract monocytes via the CCR2 axis.
Haematologica
; 102(12): 2069-2076, 2017 12.
Article
em En
| MEDLINE
| ID: mdl-28971904
ABSTRACT
Chronic lymphocytic leukemia (CLL) cells are provided with essential survival and proliferative signals in the lymph node microenvironment. Here, CLL cells engage in various interactions with bystander cells such as T cells and macrophages. Phenotypically distinct types of tumor infiltrating macrophages can either be tumor supportive (M2) or play a role in tumor immune surveillance (M1). Although recent in vitro findings suggest a protective role for macrophages in CLL, the actual balance between these macrophage subsets in CLL lymphoid tissue is still unclear. Furthermore, the mechanism of recruitment of monocytes towards the CLL lymph node is currently unknown. Both questions are addressed in this paper. Immunofluorescence staining of lymph node samples showed macrophage skewing towards an M2 tumor-promoting phenotype. This polarization likely results from CLL-secreted soluble factors, as both patient serum and CLL-conditioned medium recapitulated the skewing effect. Considering that CLL cell cytokine secretion is affected by adjacent T cells, we next studied CLL-mediated monocyte recruitment in the presence or absence of T-cell signals. While unstimulated CLL cells were inactive, T cell-stimulated CLL cells actively recruited monocytes. This correlated with secretion of various chemokines such as C-C-motif-ligand-2,3,4,5,7,24, C-X-C-motif-ligand-5,10, and Interleukin-10. We also identified CD40L as the responsible T-cell factor that mediated recruitment, and showed that recruitment critically depended on the C-C-motif-chemokine-receptor-2 axis. These studies show that the shaping of a tumor supportive microenvironment depends on cytokinome alterations (including C-C-motif-ligand-2) that occur after interactions between CLL, T cells and monocytes. Therefore, targeted inhibition of CD40L or C-C-motif-chemokine-receptor-2 may be relevant therapeutic options.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Monócitos
/
Leucemia Linfocítica Crônica de Células B
/
Transdução de Sinais
/
Movimento Celular
/
Antígenos CD40
/
Receptores CCR2
Tipo de estudo:
Prognostic_studies
Limite:
Humans
Idioma:
En
Ano de publicação:
2017
Tipo de documento:
Article