Induction of B7-H6, a ligand for the natural killer cell-activating receptor NKp30, in inflammatory conditions.

Publié dans: Blood 2013 Jul; 122(3): 394-404

Auteurs: Matta J, Baratin M, Chiche L, Forel JM, Cognet C, Thomas G, Farnarier C, Piperoglou C, Papazian L, Chaussabel D, Ugolini S, Vély F, Vivier E

Résumé

B7-H6, a member of the B7 family of immunoreceptors, is as a cell-surface ligand for the NKp30-activating receptor expressed on natural killer cells. B7-H6 is not detected in normal human tissues at steady state but is expressed on tumor cells. However, whether B7-H6 can be expressed in other conditions remains unknown. We analyzed here the pathways that lead to the expression of B7-H6 in nontransformed cells. In vitro, B7-H6 was induced at the surface of CD14(+)CD16(+) proinflammatory monocytes and neutrophils upon stimulation by ligands of Toll-like receptors or proinflammatory cytokines such as interleukin-1β and tumor necrosis factor α. In these conditions, a soluble form of B7-H6 (sB7-H6) was also produced by activated monocytes and neutrophils. In vivo, B7-H6 was expressed on circulating proinflammatory CD14(+)CD16(+) monocytes in a group of patients in sepsis conditions, and was linked to an increased mortality. sB7-H6 was selectively detected in the sera of patients with gram-negative sepsis and was associated with membrane vesicles that co-sedimented with the exosomal fraction. These findings reveal that B7-H6 is not only implicated in tumor immunosurveillance but also participates in the inflammatory response in infectious conditions.

Lien vers Pubmed [PMID] – 23687088

Lien vers le DOI – 10.1182/blood-2013-01-481705