Lab-Engineered 'Oral Cavity on a Chip' Models Bacterial, Fungal, and Viral Infections at the Gum-Tooth Interface
Researchers have developed a bioengineered microphysiological system that recreates the human gum-tooth interface, capable of modeling infections by bacteria, fungi, and SARS-CoV-2. The platform integrates vascularized human gingival tissue with tooth analogs and controlled saliva flow, enabling detailed study of host-microbe interactions. The system offers a human-relevant alternative to animal models for investigating oral disease mechanisms, including how dry mouth conditions worsen fungal infections.
A team of researchers has created a bioengineered oral microphysiological system — essentially a miniaturized, lab-grown model of the human oral cavity — that replicates the gingival-tooth interface with vascularized tissue and tooth analogs. The platform was used to study cross-kingdom biofilm formation involving the bacterium Streptococcus mutans and the fungus Candida albicans, two common oral pathogens. Single-cell RNA sequencing and global metabolomics revealed that fungal colonization triggers epithelial-to-mesenchymal transition, a cellular process associated with tissue remodeling and disease progression, accompanied by distinct transcriptional and metabolic changes. The system was also adapted to simulate SARS-CoV-2 infection, allowing researchers to observe how gingival tissue responds to live-virus challenge. Additionally, by incorporating controlled human saliva flow, the researchers demonstrated that hyposalivation — reduced saliva production — significantly amplifies the pathogenic potential of fungal infection. The study positions oral microphysiological systems as a powerful and human-relevant experimental tool for mechanistic investigation of oral infections under controlled laboratory conditions.
What's missing
The study does not report in vivo validation comparing the platform's outputs to clinical patient data, leaving open the question of how faithfully the system recapitulates the full complexity of human oral disease.
What different sources said
- bioRxivCenter
Emulating the gingival-tooth interface during bacterial, fungal, and viral infection in a microphysiological model of the human oral cavity
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