Clostridioides difficile stimulates CCL20 expression in human colonoid monolayers in a transwell-based co-culture system that supports its anaerobic growth

Zucchi, P.; Gladden, A. D.; Day, A. W.; Dressler, J.; Govind, R.; Almeqdadi, M.; Roper, J.; Tai, A.; Batorsky, R.; Kumamoto, C. A.

doi:10.64898/2026.04.28.721417

bioRxiv · 10.64898/2026.04.28.721417

Clostridioides difficile stimulates CCL20 expression in human colonoid monolayers in a transwell-based co-culture system that supports its anaerobic growth

Zucchi, P.·Gladden, A. D.·Day, A. W.·Dressler, J.·Govind, R.·Almeqdadi, M.·Roper, J.·Tai, A.·Batorsky, R.·Kumamoto, C. A.

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Abstract

The pathogenic bacterium Clostridioides difficile is a major cause of antibiotic-associated diarrheal disease. Treatment of the disease is challenging because antibiotics used for treatment may also perpetuate the conditions that contributed to initial susceptibility. Elucidating the mechanisms of C. difficile/intestinal epithelium interaction is needed to facilitate the development of new therapeutic options. The studies described in this communication demonstrate the development of a tissue culture system that supported the growth of C. difficile in co-culture with a model of the human intestinal epithelium produced from colonoids, organoids derived from human colonic biopsies. Epithelial cell responses to C. difficile included upregulation of CCL20, encoding a chemokine that was previously shown to be upregulated in response to C. difficile challenge. Additionally, bacteria associated with the monolayer in a non-toxin dependent manner. This system will support future investigation of epithelium/C. difficile interactions during CDI and identification of mechanisms that drive pathogenesis by C. difficile in the human intestine.

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Zucchi, P., Gladden, A. D., Day, A. W., Dressler, J., Govind, R., Almeqdadi, M., Roper, J., Tai, A., Batorsky, R., Kumamoto, C. A.. 2026-04-29. Clostridioides difficile stimulates CCL20 expression in human colonoid monolayers in a transwell-based co-culture system that supports its anaerobic growth. https://doi.org/10.64898/2026.04.28.721417

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