Engineered HMGB1 Construct with Tandem HMG B Domains that Promotes Tissue Regeneration without Potential for Deleterious Inflammation or Thrombosis

Vinals Guitart, A.; Lee, C.; Espirito Santo, A.; Ruan, J.-L.; Redfield, C.; Yue, W.; Burgess-Brown, N.; Fedorov, O.; Nanchahal, J.

doi:10.1101/2024.11.06.622383

bioRxiv · 10.1101/2024.11.06.622383

Engineered HMGB1 Construct with Tandem HMG B Domains that Promotes Tissue Regeneration without Potential for Deleterious Inflammation or Thrombosis

Vinals Guitart, A.·Lee, C.·Espirito Santo, A.·Ruan, J.-L.·Redfield, C.·Yue, W.·Burgess-Brown, N.·Fedorov, O.·Nanchahal, J.

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Abstract

Fully reduced High Mobility Group Box 1 (HMGB1) binds CXCL12 and signals via CXCR4 when released into the extracellular space. It acts as a chemokine and transitions stem cells from quiescent G to a primed GAlert state. Cells in GAlert rapidly enter G1 in response to activating factors released by tissue injury to promote tissue repair. However, oxidative conversion of FR-HMGB1 into the disulfide form activates proinflammatory pathways via TLR-2, TLR-4 and RAGE. Peptide mapping and NMR spectroscopy identified a conserved CXCL12-binding motif within each Box and adjacent flanking regions. We decoupled the regenerative and inflammatory functions using an engineered construct (dBB12L), comprising tandem Box B domains with a flexible linker. dBB12L exhibited CXCL12 binding and accelerated repair equivalent to FR-HMGB1. Importantly, dBB12L lacked detectable RAGE binding and did not signal via TLR-2 and TLR-4, establishing it as a potential therapeutic to promote tissue repair without deleterious inflammation.

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Vinals Guitart, A., Lee, C., Espirito Santo, A., Ruan, J.-L., Redfield, C., Yue, W., Burgess-Brown, N., Fedorov, O., Nanchahal, J.. 2024-11-07. Engineered HMGB1 Construct with Tandem HMG B Domains that Promotes Tissue Regeneration without Potential for Deleterious Inflammation or Thrombosis. https://doi.org/10.1101/2024.11.06.622383

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