Nature Biotechnology
An engineered E. coli strain sustains intratumoral nitric oxide production to boost effectiveness of tumor immunotherapy
Nature Biotechnology, Published online: 18 March 2026; doi:10.1038/s41587-026-03055-x
An engineered Escherichia coli Nissle 1917 strain carrying a synthetic arginine–nitric oxide (NO) circuit enables sustained intratumoral NO production that promotes vascular normalization and immune reprogramming. This reshaped tumor microenvironment synergizes with blockade of the immune checkpoint PD-L1 to reinvigorate CD8+ T cells and drive durable tumor regression in mouse models.