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bioRxiv · 10.1101/641589

Follicular regulatory T cells can access the germinal centre independently of CXCR5

Vanderleyden, I.·Fra-Bido, S.·Innocentin, S.·Okkenhaug, H.·Evans-Bailey, N.·Pierson, W.·Linterman, M.
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Abstract

The germinal centre (GC) response is critical for generating high-affinity humoral immunity and immunological memory, which forms the basis of successful immunisation. Control of the GC response is thought to require follicular regulatory T (Tfr) cells, a subset of suppressive Foxp3+ Treg cells located within GCs. Relatively little is known about the exact role of Tfr cells within the GC, and the mechanism/s through which they exert their suppressive function. A unique feature of Tfr cells is their reported CXCR5-dependent localisation to the GC. Here we show that the lack of CXCR5 on Foxp3+ regulatory T cells resulted in a reduced frequency, but not an absence of, GC-localised Tfr cells. This demonstrates that additional, CXCR5-independent mechanisms facilitate Treg cell homing to the GC.

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Vanderleyden, I., Fra-Bido, S., Innocentin, S., Okkenhaug, H., Evans-Bailey, N., Pierson, W., Linterman, M.. 2019-05-17. Follicular regulatory T cells can access the germinal centre independently of CXCR5. https://doi.org/10.1101/641589

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