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bioRxiv · 10.1101/2024.07.07.602413

A pumpless and tubeless microfluidic device enables extended in vitro development of Cryptosporidium parvum

Gunasekera, S.·Thierry, B.·Cheah, E.·King, B.·Monis, P.·Carr, J. M.·Chopra, A.·Watson, M.·O'Dea, M.·Ryan, U.
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Abstract

The enteric parasite Cryptosporidium remains a treatment challenge for drinking water utilities globally due to its resistance to chlorine disinfection. However, the lack of an in vitro culture system for Cryptosporidium that is both cost-effective and reliable remains a key bottleneck in Cryptosporidium research. Here we report that the microfluidic culture of HCT-8 cells under fluid shear stress enables the extended development of Cryptosporidium parvum. Specifically, the growth of C. parvum in a user-friendly pumpless microfluidic device was assessed using immunofluorescence assays, scanning electron microscopy and quantitative PCR, which revealed that development peaked at six days post-infection but continued for ten days in total. Oocysts produced within the microfluidic device were infective to fresh HCT-8 monolayers, however these oocysts were only present at low levels. We anticipate that such microfluidic approaches will facilitate a wide range of in vitro studies on Cryptosporidium and may have the potential to be further developed as a routine infectivity assessment tool for the water industry.

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Gunasekera, S., Thierry, B., Cheah, E., King, B., Monis, P., Carr, J. M., Chopra, A., Watson, M., O'Dea, M., Ryan, U.. 2024-07-08. A pumpless and tubeless microfluidic device enables extended in vitro development of Cryptosporidium parvum. https://doi.org/10.1101/2024.07.07.602413

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