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bioRxiv · 10.1101/2022.04.29.489661

Plasma membrane topography governs the three-dimensional dynamic localization of IgM B cell receptor clusters

Saltukoglu, D.·Oezdemir, B.·Holtmannspoetter, M.·Reski, R.·Piehler, J.·Kurre, R.·Reth, M.
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Abstract

B lymphocytes recognize bacterial or viral antigens via different classes of the B cell antigen receptor (BCR). Protrusive structures termed microvilli cover lymphocyte surfaces and are thought to perform sensory functions in screening antigen-bearing surfaces. Here, we have studied the cell surface features of Ramos B cells and the spatiotemporal organization of the IgM-BCR using lattice light sheet microscopy in combination with tailored custom-built 4D image analysis. Ramos B cell surfaces were found to form dynamic networks of elevated ridges bridging individual microvilli. A proportion of membrane-localized IgM-BCR was found in clusters, which were associated with the ridges and the microvilli. The dynamic ridge network organization and the IgM-BCR cluster mobility were linked and both were controlled by Arp2/3 complex activity. Our results suggest that topographical features of the cell surface govern the distribution and dynamic localization of IgM-BCR clusters to facilitate antigen screening.

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Saltukoglu, D., Oezdemir, B., Holtmannspoetter, M., Reski, R., Piehler, J., Kurre, R., Reth, M.. 2022-04-29. Plasma membrane topography governs the three-dimensional dynamic localization of IgM B cell receptor clusters. https://doi.org/10.1101/2022.04.29.489661

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