Glioma-Derived Thrombospondin-1modulates Cd14(+) Cell Tolerogenic Properties

Thrombospondin-1 (TSP1) plays a role in the immune tolerance, and is involved in the pathogenesis of glioma. This study aims to investigate the role of the glioma-derived TSP1 in the induction of the tumor immune tolerance. The results showed that the primary human glioma cells expressed high levels of TSP1. Glioma cells enhanced the expression of transforming growth factor (TGF)-beta in CD4(+) CD16-naive monocytes (Mos). The TGF-beta(+) Mos showed inhibitory effect on CD8(+) T cell proliferation. We conclude that glioma cell-derived TSP1 facilitates the induction of TGF-beta in Mos. The TSP1 may be a potential therapeutic target of glioma.