Near-infrared remote triggering of bio-enzyme activation to control intestinal colonization by orally administered microorganisms

Oral biotherapeutics hold significant promise, but their lack of controllability and targeting poses a major challenge, particularly for intestinal bacterial biotherapeutics. In response, we have developed a nanoencapsulation approach that responds to the release of enzyme activity in the organism and activates the enzyme in situ, allowing for controlled colonization of microbes in the gut. The nano-coating comprises a two-layer structure: an inner layer of polydopamine with photothermal and adhesive properties, and an outer layer of gelatin–sodium carboxymethylcellulose, which is hydrolyzed by cellulases in the gut following photothermal interaction with dopamine. We have successfully achieved controlled colonization of a wide range of microorganisms. Furthermore, in a diabetes model, this approach has had a profound impact on regulating glucagon-like peptide-1 (GLP-1) production, β-cell physiology, and promoting insulin secretion. This nanocoating is achieved by in situ activation of cellulase without the need for genetic or targeted molecular modification, representing a new paradigm and alternative strategy for microbial therapy. It not only enables precise and controlled colonization of probiotics but also demonstrates great potential for broader application in the field of oral biotherapy.

Statement of significance

We have developed a nano-encapsulation method that triggers enzyme activity in response to enzymatic activity, resulting in the controlled release and adhesion of a wide range of microorganisms in the gut. The nano coating comprises two layers: an inner layer of polydopamine with photothermal and adhesion properties, and an outer layer of a gelatin-sodium carboxymethylcellulose polymer, which can be hydrolyzed by cellulases in the intestine. Additionally, this method allows for the preparation of various microbial coatings. This approach holds significant promise for regulating GLP-1 production, the physiological function of pancreatic β-cells, and promoting insulin secretion in diabetes models.