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bioRxiv · 10.1101/2024.10.27.620510

Modulation of Host Cell Membrane Biophysics Dynamics by Neospora caninum: A Study Using LAURDAN Fluorescence with Hyperspectral Imaging and Phasor Analysis

Diaz, M.·Robello, C.·Cabrera, A.·Malacrida, L. S.
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Abstract

Neospora caninum is known to manipulate host cell organelles and recruit lipids for its survival. However, the impact of this lipid redistribution on host cell membranes remains poorly understood. This study used LAURDAN fluorescence, hyperspectral imaging, and phasor plot analysis to investigate how N. caninum modifies membrane order in Vero cells. The results revealed a significant decrease in host cell plasma and internal membrane order upon infection, suggesting that cholesterol is redistributed from the host plasma membrane to the parasitophorous vacuoles. To mimic cholesterol depletion, uninfected cells were treated with methyl-{beta}-cyclodextrin (MBCD), which increased membrane fluidity. Conversely, replenishing infected cells with cholesterol-loaded MBCD restored membrane fluidity to levels lower than control cells, indicating cholesterol enrichment. These findings provide novel insights into how N. caninum modulates host cell membrane dynamics through lipid manipulation, potentially aiding its intracellular survival.

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Diaz, M., Robello, C., Cabrera, A., Malacrida, L. S.. 2024-10-29. Modulation of Host Cell Membrane Biophysics Dynamics by Neospora caninum: A Study Using LAURDAN Fluorescence with Hyperspectral Imaging and Phasor Analysis. https://doi.org/10.1101/2024.10.27.620510

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