Inflammatory bowel diseases (IBDs) are often associated with elevated levels of reactive oxygen species (ROS) and highly dysregulated gut microbiota. In this study, we synthesized a polymer of hyaluronic acid–poly(propylene sulfide) (HA-PPS) and developed ROS-scavenging nanoparticles (HPN) that could effectively scavenge ROS. To achieve colon tissue targeting effects, the HPN nanoparticles were conjugated to the surface of modified probiotic Escherichia coli Nissle 1917 (EcN). To enhance the bacteriotherapy of EcN, we encapsulated EcN cells with a poly-norepinephrine (NE) layer that can protect EcN against environmental assaults to improve the viability of EcN in oral delivery and prolong the retention time of EcN in the intestine due to its strong mucoadhesive capability. In the dextran sulfate sodium–induced mouse colitis models, HPN-NE-EcN showed substantially enhanced prophylactic and therapeutic efficacy. Furthermore, the abundance and diversity of gut microbiota were increased after treatment with HPN-NE-EcN, contributing to the alleviation of IBDs.

Immunotherapy strategies that use cell‐based delivery systems have sparked much interest in the treatment of malignancies, owing to their high biocompatibility, excellent tumor targeting capability, and unique biofunctionalities in the tumor growth process. A variety of design principles for cell‐based immunotherapy, including cell surface decoration, cell membrane coating, cell encapsulation, genetically engineered cell, and cell‐derived exosomes, give cancer immunotherapy great potential to improve therapeutic efficacy and reduce adverse effects. However, the treatment efficacy of cell‐based delivery methods for immunotherapy is still limited, and practical uses are hampered due to complex physiological and immunological obstacles, such as physical barriers to immune infiltration, immunosuppressive tumor microenvironment, upregulation of immunosuppressive pathways, and metabolic restriction. In this review, we present an overview of the design principles of cell‐based delivery systems in cancer immunotherapy to maximize the therapeutic impact, along with anatomical, metabolic, and immunological impediments in using cell‐based immunotherapy to treat cancer. Following that, a summary of novel delivery strategies that have been created to overcome these obstacles to cell‐based immunotherapeutic delivery systems is provided. Also, the obstacles and prospects of next‐step development of cell‐based delivery systems for cancer immunotherapy are concluded in the end.

CXCR4 antagonistic nanocomplex regulates the immune process to enhance anti–PD-L1 immunotherapy.

Cell-based therapy holds great potential to address unmet medical needs and revolutionize the healthcare industry, as demonstrated by several therapeutics such as CAR-T cell therapy and stem cell transplantation that have achieved great success clinically. Nevertheless, natural cells are often restricted by their unsatisfactory in vivo trafficking and lack of therapeutic payloads. Chemical engineering offers a cost-effective, easy-to-implement engineering tool that allows for strengthening the inherent favorable features of cells and confers them new functionalities. Moreover, in accordance with the trend of precision medicine, leveraging chemical engineering tools to tailor cells to accommodate patients individual needs has become important for the development of cell-based treatment modalities. This review presents a comprehensive summary of the currently available chemically engineered tools, introduces their application in advanced diagnosis and precision therapy, and discusses the current challenges and future opportunities.