(A) BCG infection of urothelial cells leads to the release of cytokines, such as IL-8. (B) Neutrophils compose the early responding cells to BCG; BCG stimulates release of TRAIL in addition to chemotactic factors. (C) Inflammatory effector cells, such as T cells and macrophages, respond to the neutrophil-secreted chemotactic signals. (D) Cytotoxic cells and TRAIL lead to tumor apoptosis.
BCG: Bacille Calmette–Guerin; TRAIL: TNF-related apoptosis-inducing ligand.