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bioRxiv · 10.1101/403592

In vivo function of the lipid raft protein Flotillin 1 during CD8+ T cell-mediated host surveillance

Ficht, X.·Ruef, N.·Stolp, B.·Moalli, F.·Page, N.·Merkler, D.·Nichols, B. J.·Diz-Munoz, A.·Niggli, V.·Stein, J.
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Abstract

Flotillin-1 (Flot1) is a highly conserved, ubiquitously expressed lipid raft-associated scaffolding protein. Migration of Flot1-deficient neutrophils is impaired due to a decrease in myosin II-mediated contractility. Flot1 also accumulates in the uropod of polarized T cells, suggesting an analogous role in T cell migration. Here, we analyzed morphology and migration of naive and memory WT and Flot1-/- CD8+ T cells in lymphoid and non-lymphoid tissues with intravital two-photon microscopy, as well as their clonal expansion during antiviral immune responses. Flot1-/- CD8+ T cells displayed minor alterations in cell shape and motility parameters in vivo but showed comparable homing to lymphoid organs and infiltration into non-lymphoid tissues. Taken together, Flot1 plays a detectable but unexpectedly minor role for CD8+ T cell behavior under physiological conditions.

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Ficht, X., Ruef, N., Stolp, B., Moalli, F., Page, N., Merkler, D., Nichols, B. J., Diz-Munoz, A., Niggli, V., Stein, J.. 2018-08-29. In vivo function of the lipid raft protein Flotillin 1 during CD8+ T cell-mediated host surveillance. https://doi.org/10.1101/403592

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