Adaptive immunity to retroelements promotes barrier integrity

Wells, A. C.; Lima-Junior, D. S.; Link, V. M.; Smelkinson, M.; Krishnamurthy, S. R.; Chi, L.; Segrist, E.; Rivera, C. A.; Teijeiro, A.; Bouladoux, N.; Belkaid, Y.

doi:10.1101/2024.08.09.606346

bioRxiv · 10.1101/2024.08.09.606346

Adaptive immunity to retroelements promotes barrier integrity

Wells, A. C.·Lima-Junior, D. S.·Link, V. M.·Smelkinson, M.·Krishnamurthy, S. R.·Chi, L.·Segrist, E.·Rivera, C. A.·Teijeiro, A.·Bouladoux, N.·Belkaid, Y.

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Abstract

Maintenance of tissue integrity is a requirement of host survival. This mandate is of prime importance at barrier sites that are constitutively exposed to the environment. Here, we show that exposure of the skin to non-inflammatory xenobiotics promotes tissue repair; more specifically, mild detergent exposure promotes the reactivation of defined retroelements leading to the induction of retroelement-specific CD8+ T cells. These T cell responses are Langerhans cell dependent and establish tissue residency within the skin. Upon injury, retroelement-specific CD8+ T cells significantly accelerate wound repair via IL-17A. Collectively, this work demonstrates that tonic environmental exposures and associated adaptive responses to retroelements can be coopted to preemptively set the tissue for maximal resilience to injury.

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Wells, A. C., Lima-Junior, D. S., Link, V. M., Smelkinson, M., Krishnamurthy, S. R., Chi, L., Segrist, E., Rivera, C. A., Teijeiro, A., Bouladoux, N., Belkaid, Y.. 2024-08-09. Adaptive immunity to retroelements promotes barrier integrity. https://doi.org/10.1101/2024.08.09.606346

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