Polybacterial Intracellular Macromolecules Shape Single-Cell Epikine Profiles in Upper Airway Mucosa

Area of Science:

• Immunology
• Microbiology
• Cell Biology

Background:

• The upper airway epithelium acts as a barrier against microbes.
• Nasal and oral mucosal sites are prone to dysbiosis and inflammation.
• Host-microbe interactions in these tissues are crucial for health.

Purpose of the Study:

• To investigate host-microbial interactions within human oral mucosal epithelial cells.
• To identify bacterial signatures and their impact on epithelial cell responses.
• To explore the role of persistent bacterial macromolecules in cellular function and drug response.

Main Methods:

• Reanalysis of single-cell RNA sequencing data from human oral mucosa.
• Detection of bacterial macromolecules (rRNA, mRNA, glycolipids) in oral keratinocytes using in situ hybridization and immunohistochemistry.
• In vitro and in vivo experiments challenging cells with bacterial components and analyzing epikine expression.
• Application of the Drug2Cell algorithm for drug efficacy prediction.

Main Results:

• Polybacterial signatures were identified in oral epithelial and stromal cells.
• Persistent bacterial macromolecules (PIMs) were detected within human oral keratinocytes.
• Higher PIM concentrations correlated with enhanced receptor-ligand signaling and epikine expression.
• Endogenous lipoteichoic acid, not lipopolysaccharide, directly influenced epikine expression.
• PIM detection altered drug efficacy predictions.

Conclusions:

• Polybacterial intracellular macromolecules (PIMs) persist in mucosal epithelial cells.
• PIMs linearly drive single-cell effector cytokine expression.
• PIMs influence drug responses, impacting therapeutic strategies.
• Understanding PIMs is vital for comprehending host-microbe dynamics in health and disease at a single-cell level.