The article reported by the team of Liang Xiaolong and Ma Xiaotu from the Ultrasound Medicine Department of Peking University Third Hospital, from the perspective of biomaterials, the most remarkable aspect is not "another engineered bacterium was created", but that the authors truly connected metabolic engineering, tumor microenvironment remodeling, and immune checkpoints into a closed loop. The article used the engineered probiotic E. coli Nissle 1917 to continuously produce NO within the tumor, not just providing gas molecules temporarily, but turning the bacteria into a long-term "in situ NO factory". The result was that it not only promoted the normalization of tumor blood vessels and alleviated hypoxia, but also improved the immunosuppressive microenvironment, promoted the recruitment of DCs, and cooperated with αPD-L1 to amplify the CD8⁺ T cell response, ultimately achieving persistent tumor suppression and even long-term immune memory in various solid tumor models.
The related research was published in Nature Biotechnology under the title "Sustained nitric oxide production by engineered E. coli remodels the tumor microenvironment and potentiates immunotherapy". Xu Shuqi, a 2022-level doctoral student from Peking University Third Hospital, and Zhang Tianjiao, a 2023-level doctoral student, are the co-first authors of the paper, while Researcher Liang Xiaolong and Associate Researcher Ma Xiaotuo are the co-corresponding authors.