Induction of ASC pyroptosis requires gasdermin D or caspase-1/11-dependent mediators and IFNβ from pyroptotic macrophages

Abstract

Mesenchymal stem cells (MSCs) have been used in cell-based therapies for a variety of disorders. Some factors such as inflammatory mediators in the diseased area might damage the survival of MSCs and affect their efficacy. Pyroptosis is a form of programmed necrosis as a response for immune cells to cytosolic pathogenic stimuli. Whether MSCs develop pyroptosis under pathological stimulation, its underlying mechanism and biological significance are still unclear. Here, we found that LPS, flagellin, dsDNA, nigericin (NIG), or LPS combined with nigericin (LPS/NIG) could not induce pyroptosis in adipose-tissue-derived mesenchymal stem cells (ASCs). However, when applied the culture media collected from LPS/NIG-induced pyroptotic bone marrow-derived macrophages (BMDMs) to incubate ASCs, ASCs developed pyroptosis. Inhibition of caspases or deletion of Caspase-1/11 in ASCs did not affect the pyroptotic macrophage media-triggered ASC pyroptosis while ablation of Caspase-1/11 abolished BMDM pyroptosis induced by LPS/NIG. Media collected from LPS/NIG stimulated Gsdmd −/− or Caspase-1/11 −/− BMDMs could not induce pyroptosis of ASCs. In addition, RNA-seq analysis showed that interferon (IFN)-stimulated genes were upregulated in pyroptotic ASCs. Adding IFNβ could boost LPS/NIG stimulated BMDM media-induced ASC pyroptosis. Surprisingly, the pyroptotic ASCs had a lower bactericidal ability to P. Aeruginosa. Taken together, induction of ASC pyroptosis requires gasdermin D or caspase-1/11-dependent mediators and IFNβ from pyroptotic macrophages.

Delivery of Ultrasmall Nanoparticles to the Cytosolic Compartment of Pyroptotic J774A.1 Macrophages via GSDMDNterm Membrane Pores

“…To address the possibility that small-sized NPs enter cells through GSDMD Nterm membrane pores, we activated GSDMD cleavage with nigericin (Nig) or adenosine triphosphate (ATP) after priming the cells with lipopolysaccharide (LPS). ,− Western blot analysis verified that anti-GSDMD antibody recognized the N-terminal 31-kDa pore-forming pyroptotic fragment GSDMD Nterm when cells were incubated with Nig or LPS/Nig (Figure a). LDH release (Figure b), real-time cell permeability (Figure c), and PI staining flow cytometric assays (Figure S3) verified the formation of GSDMD Nterm membrane pores.…”

Effects of Exosomes Derived from Adipose-Derived Mesenchymal Stem Cells on Pyroptosis and Regeneration of Injured Liver

“…However, it is worth mentioning that although ADSCs could reduce the expression of inflammatory response-related proteins such as NLRP3 in the liver tissues, they significantly increased the expression of GSDMD protein. This may be due to the release of IFN-β from macrophages at the injury site, which stimulates ADSCs after recruitment to the injury site, resulting in pyroptosis, so the examination of liver tissue results in the ADSC intervention group revealed elevated GSDMD expression [ 26 ]. However, this requires further validation, and in order to confirm whether ADSCs do not lead to more GSDMD expression when macrophages are lacking, rat primary hepatocytes injured by hypoxia–reoxygenation were intervened with ADSCs in vitro.…”

Jinwujiangu Capsule Treats Fibroblast-Like Synoviocytes of Rheumatoid Arthritis by Inhibiting Pyroptosis via the NLRP3/CAPSES/GSDMD Pathway

“…Pyroptosis is divided into classical and nonclassical pathways according to the caspases [30]. In the classical pathway, inflammasomes are polymeric protein complexes composed of PRR, procaspase-1, and ASC, which activate caspase-1 [31][32][33][34]. Subsequently, active caspase-1 converts pro-IL-1β and pro-IL-18 into mature IL-1β and IL-18 [35].…”