Antagonistic nanobodies implicate mechanism of GSDMD pore formation and potential therapeutic application.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 39327452.
- Also identified by DOI 10.1038/s41467-024-52110-1 and PMC identifier 11427689.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Inflammasome activation results in the cleavage of gasdermin D (GSDMD) by pro-inflammatory caspases. The N-terminal domains (GSDMD<sup>NT</sup>) oligomerize and assemble pores penetrating the target membrane. As methods to study pore formation in living cells are insufficient, the order of conformational changes, oligomerization, and membrane insertion remained unclear. We have raised nanobodies (VHHs) against human GSDMD and find that cytosolic expression of VHH<sub>GSDMD-1</sub> and VHH<sub>GSDMD-2</sub> prevents oligomerization of GSDMD<sup>NT</sup> and pyroptosis. The nanobody-stabilized GSDMD<sup>NT</sup> monomers partition into the plasma membrane, suggesting that membrane insertion precedes oligomerization. Inhibition of GSDMD pore formation switches cell death from pyroptosis to apoptosis, likely driven by the enhanced caspase-1 activity required to activate caspase-3. Recombinant antagonistic nanobodies added to the extracellular space prevent pyroptosis and exhibit unexpected therapeutic potential. They may thus be suitable to treat the ever-growing list of diseases caused by activation of (non-) canonical inflammasomes.
Medical subject headings
- Single-Domain Antibodies
- Inflammasomes
- Phosphate-Binding Proteins
- Pyroptosis
- Intracellular Signaling Peptides and Proteins