INTRODUCTION: The growing global awareness of bacterial pathogens is highlighting previously underestimated organisms and their contribution to established infections. Wohlfahrtiimonas chitiniclastica has been lately identified in chronic, non-healing diabetic foot ulcers (DFUs), highlighting its emerging role in these infections.

METHODS: To explore host-pathogen interactions, an epithelial cell line A549 and monocyte cell line THP-1 cells were infected with W. chitiniclastica. Gene expression profiling was conducted. To mimic diabetic conditions, infections were performed under varying glucose levels, followed by PCR for cytokine analysis. To assess potential effects on wound healing, a scratch assay was performed on epithelial cells infected with W. chitiniclastica for 24 h, using a Keyence BZ-X800 microscope for analysis.

RESULTS: While no significant direct effect on epithelial cells was detected, the lack of a beneficial cellular response may still promote delayed wound healing and thereby contribute to disease progression. However, it elicited a pronounced activation of THP-1 monocytes, characterized by elevated cytokine production. Notably, cytokine expression in THP-1 cells was attenuated under high-glucose conditions. Surprisingly, the scratch assay revealed a significant delay in cell line closure in the presence of all W. chitiniclastica isolates or their supernatants. Additionally, all strains demonstrated robust growth in different glucose concentration environments, with no significant differences observed.

CONCLUSION: These findings suggest that W. chitiniclastica modulates immune responses in a glucose-dependent manner, potentially enabling immune evasion in the inflammatory environment of DFUs. W. chitiniclastica isolates significantly delayed wound closure, indicating a potential role in impaired chronic wound healing. Furthermore, W. chitiniclastica's ability to grow in hyperglycaemic conditions without classical fermentation indicates oxidative glucose metabolism and a survival advantage.