Provided are a method of screening an inhibitor of caspase activity by lipopolysaccharide and a method of screening a therapeutic agent for inflammatory diseases or sepsis using the same. Accordingly, it is possible to develop a caspase-4-specific inhibitor.

It is disclosed herein that RPE degeneration in human cell culture and in mouse models is driven by a non-canonical inflammasome pathway that results in activation of caspase-4 (also known as caspase-11 in mouse) and caspase-1, and requires cyclic GMP-AMP synthase (cGAS)-dependent interferon- (IFN-) production and gasdermin D-dependent interleukin-18 (IL-18) secretion. Reduction of DICER1 or accumulation of Alu RNA triggers cytosolic escape of mitochondrial DNA, which engages cGAS. Collectively, these data highlight an unexpected role for cGAS in responding to mobile element transcripts, reveal cGAS-driven interferon signaling as a conduit for mitochondrial damage-induced NLRP3 activation, and expand the immune sensing repertoire of cGAS and caspase-4 to non-infectious human disease. Coupled with the unexpected result that caspase-4, gasdermin D, IFN-, and cGAS are elevated in the RPE of human eyes with geographic atrophy, these findings also identify new targets for a major cause of blindness.

Provided is a method of producing monomeric caspase activation and recruitment domains (CARDs) in bacteria. According to this method, CARD domains may be easily produced in a monomeric form. Monomeric CARDs may be applied to studies on the mechanism of action of caspase, the development of new drugs, detection and elimination of endotoxins, development of cosmetics, etc.

It is disclosed herein that RPE degeneration in human cell culture and in mouse models is driven by a non-canonical inflammasome pathway that results in activation of caspase-4 (also known as caspase-11 in mouse) and caspase-1, and requires cyclic GMP-AMP synthase (cGAS)-dependent interferon-? (IFN-?) production and gasdermin D-dependent interleukin-18 (IL-18) secretion. Reduction of DICER1 or accumulation of Alu RNA triggers cytosolic escape of mitochondrial DNA, which engages cGAS. Collectively, these data highlight an unexpected role for cGAS in responding to mobile element transcripts, reveal cGAS-driven interferon signaling as a conduit for mitochondrial damage-induced NLRP3 activation, and expand the immune sensing repertoire of cGAS and caspase-4 to non-infectious human disease. Coupled with the unexpected result that caspase-4, gasdermin D, IFN-?, and cGAS are elevated in the RPE of human eyes with geographic atrophy, these findings also identify new targets for a major cause of blindness.

Provided are a method of screening an inhibitor of caspase activity by lipopolysaccharide and a method of screening a therapeutic agent for inflammatory diseases or sepsis using the same. Accordingly, it is possible to develop a caspase-4-specific inhibitor.

Provided is a method of producing monomeric caspase activation and recruitment domains (CARDs) in bacteria. According to this method, CARD domains may be easily produced in a monomeric form. Monomeric CARDs may be applied to studies on the mechanism of action of caspase, the development of new drugs, detection and elimination of endotoxins, development of cosmetics, etc.

An amyotrophic lateral sclerosis (ALS)-simulating model and a method for constructing the ALS-simulating model based on a caspase-4 (CASP4) gene are provideds. The method includes: (1) constructing a targeting fragment for knock-in of the CASP4 gene; (2) injecting gRNA, Cas9 mRNA, and the targeting fragment into a mouse zygote, culturing, and passaging to produce a hCASP4flox mouse with the CASP4 gene stably inherited; and (3) crossing the hCASP4flox mouse with a Cre driver mouse to produce a double-positive heterozygous mouse, which is a mouse model in which the CASP4 gene is specifically expressed in a nervous system. An ALS-simulating animal model is constructed based on a humanized CASP4 gene. The method can effectively avoid the mouse death caused by this apoptotic factor, and leads to an ALS-simulating mouse model in which TDP-43 fragments accumulate in the cytoplasm and TDP-43 is deleted in the nucleus.