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bioRxiv · 10.64898/2026.01.27.702115

Establishment of Galleria mellonella as a Model for Achromobacter xylosoxidans Infection

Abstract

Achromobacter xylosoxidans (Ax) is an emerging pathogen with a strong capacity to adapt to different niches, but its pathogenesis is poorly understood. To investigate the virulence of this versatile bacterium, alternative infection models are valuable. Galleria mellonella wax moth presents cost and ethical advantages as an in vivo infection model. Here, we investigate the utility of Galleria as a model of Ax infection and demonstrate that mortality following Ax infection in Galleria recapitulates survival outcomes observed in infected mice. We further show that the Galleria infection model can be used to examine antimicrobial activity against Ax. Visualization of hemocytes suggested that Ax was internalized into immune cells, similar to what is observed in vertebrate models. Overall, our work establishes Galleria mellonella as a model of Ax infection that mirrors disease severity and innate immune cell interactions in murine models.

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Lam, H. N., Lloyd, C., Wimbush, B., Lam, N. T., Adams, P., Acharya, P.. 2026-01-27. Establishment of Galleria mellonella as a Model for Achromobacter xylosoxidans Infection. https://doi.org/10.64898/2026.01.27.702115

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