CD25 and indoleamine 2,3-dioxygenase are up-regulated by prostaglandin E2 and expressed by tumor-associated dendritic cells in vivo: additional mechanisms of T-cell inhibition
Molecular Tumor Biology and Tumor Immunology, the Clinic I for Internal Medicine, Hematology and Oncology, the Institute of Neurophysiology, and the Institute for Pathology, University Hospital at the University of Cologne, Germany.