Soluble B7-H1: differences in production between dendritic cells and T cells

Immunol Lett. 2012 Feb 29;142(1-2):78-82. doi: 10.1016/j.imlet.2011.11.001. Epub 2011 Nov 25.


Tumor cells aberrantly express several T cell inhibitory molecules including members of the B7-H co-regulatory family. Presumably tumor-expressed B7-H1 and B7-H3 confer resistance to elimination by the immune system. In addition, elevated levels of soluble B7-H1 (sB7-H1) has been identified in the sera of cancer patients, including renal carcinoma patients and is associated with increased cancer related death. Here we report that sB7-H1 is produced and released by activated mature dendritic cells (mDC). Immature DC, macrophages, monocytes, or T cells are refractory to releasing sB7-H1. Exposure of CD4+ and CD8+ T cells to mDC-derived sB7-H1 molecules induced apoptosis. These data suggest that the immunobiology of B7-H1 is perhaps more complex than previously thought. sB7-H1 molecules may represent an unanticipated contributing factor to immune homeostasis. That both immune and tumor cells can be sources of sB7-H1 suggests that optimization of co-regulatory blockade immunotherapy for solid malignancies of necessity will require impact of targeting tumor and immune-derived B7-H1 molecules.

Publication types

  • Letter
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apoptosis
  • B7-H1 Antigen / biosynthesis*
  • Carcinoma, Renal Cell / immunology
  • Dendritic Cells / immunology
  • Dendritic Cells / metabolism*
  • Homeostasis / immunology*
  • Humans
  • Kidney Neoplasms / immunology
  • Lymphocyte Activation / immunology
  • Solubility
  • T-Lymphocytes / immunology
  • T-Lymphocytes / metabolism*


  • B7-H1 Antigen