Oral Mucosal Immunology and Epithelial Biology

The oral mucosa represents a dynamic interface between the external environment and systemic health. A stratified squamous epithelium, underpinned by a connective-tissue lamina propria, forms a physical barrier equipped with specialised intercellular junctions and antimicrobial peptide secretion. Resident immune cells—including dendritic cells, tissue-resident macrophages and specialised T lymphocytes—surveil this mucosal surface, maintaining a balance between tolerance of commensal microorganisms and rapid responses to pathogenic threats. Homeostasis is sustained through reciprocal signalling: epithelial cells release cytokines and chemokines that recruit or modulate immune cells, while microbial products and mechanical stimuli train the local immune network. Disruption of this equilibrium, as in gingivitis or periodontitis, leads to dysbiosis, chronic inflammation and tissue destruction. Advances in tissue engineering and in vitro modelling now permit precise dissection of host–microbe interactions, barrier function and inflammatory cascades, offering new avenues for therapeutic development in both oral and systemic disease contexts.

Research from Nature Portfolio

A novel microfluidic organ-on-chip model incorporating keratinocytes, fibroblasts and endothelial cells has demonstrated sustained mucosal barrier integrity and controlled induction of gingival inflammation over a 28-day period. By administering inflammatory cytokines and testing small-molecule inhibitors, this system has pinpointed targets that both mitigate barrier disruption and promote tissue recovery, providing a scalable platform for preclinical drug screening. An organotypic reconstructed gingiva model exposed to complex commensal biofilm communities revealed that non-pathogenic oral microbiota actively enhance epithelial stratification and amplify production of antimicrobial peptides such as elafin and human β-defensins, underlining the positive role of commensals in barrier fortification. A complementary proteomic study of an 11-species subgingival biofilm co-culture with gingival tissue identified regulated human proteins involved in cytoskeletal rearrangement, stress responses and antigen presentation, alongside bacterial proteins whose abundance shifts in early host-pathogen dialogue, offering a systems-level view of periodontal pathogenesis.

Oral Mucosal Immunology and Epithelial Biology publication trend

The graph below shows the total number of articles in oral mucosal immunology and epithelial biology across all publications each year (not limited to Nature Index journals).

Technical terms

Mucosal barrier: The multi-layered epithelial interface that prevents microbial invasion while permitting selective absorption and immune surveillance.

Stratified epithelium: An arrangement of epithelial cells in multiple layers, with basal proliferative cells giving rise to differentiated superficial cells.

Biofilm: A structured microbial community adherent to a surface and enmeshed in an extracellular matrix, often exhibiting altered susceptibility to host defences and antimicrobials.

Cytokine: A small secreted protein that mediates intercellular communication in immune responses and tissue homeostasis.

Microfluidic organ-on-chip model: A miniaturised device that replicates organ-level functions and microenvironmental cues, enabling controlled study of tissue physiology and pathophysiology.

References

1. Tissue-Specific Immunity at the Oral Mucosal Barrier. Trends in Immunology (2017).
2. Oral Mucosal Epithelial Cells. Frontiers in Immunology (2019).
3. A high-throughput, 28-day, microfluidic model of gingival tissue inflammation and recovery. Communications Biology (2023).
4. Multi-species oral biofilm promotes reconstructed human gingiva epithelial barrier function. Scientific Reports (2018).
5. Proteomic profiling of host-biofilm interactions in an oral infection model resembling the periodontal pocket. Scientific Reports (2015).
6. Three‐Dimensional Humanized Model of the Periodontal Gingival Pocket to Study Oral Microbiome. Advanced Science (2023).
7. Organotypic model of the gingiva for studying bacterial and viral pathogens implicated in periodontitis. Journal of Oral Microbiology (2023).
8. A review of co-culture models to study the oral microenvironment and disease. Journal of Oral Microbiology (2020).