are responsible for significant disease burden in humans, ranging from recurrent disease outbreaks (yersiniosis) to pandemics (
plague). Together with rising antibiotic resistance rates, there is a ...critical need to better understand
pathogenesis and host immune mechanisms, as this information will aid in developing improved immunomodulatory therapeutics. Inflammasome responses in human cells are less studied relative to murine models of infection, though recent studies have uncovered key differences in inflammasome responses between mice and humans. Here, we dissect human intestinal epithelial cell and macrophage inflammasome responses to
. Our findings provide insight into species- and cell type-specific differences in inflammasome responses to
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The PARP inhibitor (PARPi) talazoparib may potentiate activity of chemotherapy and toxicity in cells vulnerable to DNA damage.
This phase I study evaluated the safety, tolerability, pharmacokinetics, ...and efficacy of talazoparib and carboplatin. Pharmacokinetic modeling explored associations between DNA vulnerability and hematologic toxicity.
Twenty-four patients (eight males; 16 females) with solid tumors were enrolled in four cohorts at 0.75 and 1 mg daily talazoparib and weekly carboplatin (AUC 1 and 1.5, every 2 weeks or every 3 weeks), including 14 patients (58%) with prior platinum treatment. Dose-limiting toxicities included grade 3 fatigue and grade 4 thrombocytopenia; the MTD was not reached. Grade 3/4 toxicities included fatigue (13%), neutropenia (63%), thrombocytopenia (29%), and anemia (38%). After cycle 2's dose, delays/reductions were required in all patients. One complete and two partial responses occurred in germline BRCA1/2 (gBRCA1/2) patients. Four patients showed stable disease beyond 4 months, three of which had known mutations in DNA repair pathways. Pharmacokinetic toxicity modeling suggests that after three cycles of carboplatin AUC 1.5 every 3 weeks and talazoparib 1 mg daily, neutrophil counts decreased 78% confidence interval (CI), 87-68 from baseline in gBRCA carriers and 63% (CI, 72-55) in noncarriers (
< 0.001). Pharmacokinetic toxicity modeling suggests an intermittent, pulse dosing schedule of PARP inhibition, differentiated by gBRCA mutation status, may improve the benefit/risk ratio of combination therapy.
Carboplatin and talazoparib showed efficacy in DNA damage mutation carriers, but hematologic toxicity was more pronounced in gBRCA carriers. Carboplatin is best combined with intermittent talazoparib dosing differentiated by germline and somatic DNA damage mutation carriers.
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Inflammasomes are multiprotein signaling complexes that activate the innate immune system. Canonical inflammasomes recruit and activate caspase-1, which then cleaves and activates IL-1β and IL-18, as ...well as gasdermin D (GSDMD) to induce pyroptosis. In contrast, non-canonical inflammasomes, caspases-4/-5 (CASP4/5) in humans and caspase-11 (CASP11) in mice, are known to cleave GSDMD, but their role in direct processing of other substrates besides GSDMD has remained unknown. Here, we show that CASP4/5 but not CASP11 can directly cleave and activate IL-18. However, CASP4/5/11 can all cleave IL-1β to generate a 27-kDa fragment that deactivates IL-1β signaling. Mechanistically, we demonstrate that the sequence identity of the tetrapeptide sequence adjacent to the caspase cleavage site regulates IL-18 and IL-1β recruitment and activation. Altogether, we have identified new substrates of the non-canonical inflammasomes and reveal key mechanistic details regulating inflammation that may aid in developing new therapeutics for immune-related disorders.
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•Human CASP4/5 directly process IL-18 at D36 to generate the activated cytokine•CASP4/5 cleave IL-1β at D27 into a p27 species that inactivates downstream IL-1R signaling•The tetrapeptide sequence of IL-18 and IL-1β regulates their processing by caspases•CASP11 can process IL-1β into the deactivating p27 species but does not process IL-18
Exconde et al. report that the non-canonical inflammasomes directly process IL-18 and IL-1β. The tetrapeptide sequence regulates IL-18 and IL-1β processing to generate an active or inactive cytokine respectively. These results suggest that the non-canonical inflammasomes directly modulate inflammation and may have a broader substrate repertoire than previously known.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Intracellular immune complexes known as inflammasomes sense breaches of cytosolic sanctity. Inflammasomes promote downstream proinflammatory events, including interleukin-1 (IL-1) family cytokine ...release and pyroptotic cell death. The nucleotide-binding leucine-rich repeat family, apoptosis inhibitory protein/nucleotide-binding leucine-rich repeat family, caspase recruitment domain (CARD) domain-containing protein 4 (NAIP/NLRC4) inflammasome is involved in a range of pathogenic and protective inflammatory processes in mammalian hosts. In particular, the NAIP/NLRC4 inflammasome responds to flagellin and components of the virulence-associated type III secretion (T3SS) apparatus in the host cytosol, thereby allowing it to be a critical mediator of host defense during bacterial infection. Notable species- and cell type-specific differences exist in NAIP/NLRC4 inflammasome responses to bacterial pathogens. With a focus on Salmonella enterica serovar Typhimurium as a model pathogen, we review differences between murine and human NAIP/NLRC4 inflammasome responses. Differences in NAIP/NLRC4 inflammasome responses across species and cell types may have arisen in part due to evolutionary pressures.
•Mice express several different NAIPs, each recognizing a specific bacterial ligand.•Humans express one functional NAIP, which broadly detects multiple bacterial ligands.•NAIP inflammasome in murine intestinal epithelial cells (IECs) controls Salmonella.•NAIP inflammasome controls Salmonella in human macrophages but not in human IECs.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In this paper, I examine the relation between law and morality within the context of Kant’s late work The Metaphysics of Morals. I argue that Kant’s conception of the law is based on a fundamental ...distinction between Right and Virtue, which respectively correspond to his legal-political theory and moral philosophy. My analysis is two part: in the first part, I examine the relationship between the Doctrines of Right and Virtue within the Kantian architectonic; in the second, I evaluate two cases of adjudication in the Rechtslehre that exemplify the distinction between law and morality explicated in the preceding section. I begin by showing that Kant’s legal and moral philosophies are normatively distinct, insofar as Right and Virtue belong to incommensurable realms of freedom and necessity. From this distinction, I derive Kant’s conception of the legal state as principally concerned with external freedoms and the preservation of the lawful condition itself. The second part of this paper analyzes Kant’s views on two cases of criminal justice, revealing his prioritization of the political over independent ethical considerations in juridical decision-making. Here, the conceptual barrier between law and morality serves as a caveat against facile recourses to Kantian ethics as means of legitimizing juridico-political decisions.
3D bioprinting of granular hydrogels comprising discrete hydrogel microparticles (microgels) may overcome the intrinsic structural limitations of bulk (nanoporous) hydrogel bioinks, enabling the ...fabrication of modular thick tissue constructs. The additive manufacturing of granular scaffolds has predominantly relied on highly jammed microgels to render the particulate suspensions shear yielding and extrudable. This inevitably compromises void spaces between microgels (microporosity), defeating rapid cell penetration, facile metabolite and oxygen transfer, and cell viability. Here, this persistent bottleneck is overcome by programming microgels with reversible interfacial nanoparticle self‐assembly, enabling the fabrication of nanoengineered granular bioinks (NGB) with well‐preserved microporosity, enhanced printability, and shape fidelity. The microporous architecture of bioprinted NGB constructs permits immediate post‐printing 3D cell seeding, which may expand the library of bioinks via circumventing the necessity of bioorthogonality for cell‐laden scaffold formation. This work opens new opportunities for the 3D bioprinting of tissue engineering microporous scaffolds beyond the traditional biofabrication window.
A nanoengineered granular bioink (NGB) is developed to enable the extrusion 3D bioprinting of hydrogel microparticle (microgel)‐based scaffolds with preserved interconnected microporosity. The reversible self‐assembly of heterogeneously charged colloidal nanoplatelets adsorbed onto gelatin methacryloyl (GelMA) microgels enables the extrudability and shape fidelity of NGB at a low packing state without filling the void spaces among the microgels.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Abstract
Legionella pneumophila is a facultative intracellular bacterial pathogen that is responsible for a pneumonia called Legionnaire’s disease. Legionella invades cells by using a type IV ...secretion system that delivers effector proteins into the host cell cytosol to facilitate its intracellular survival and replication. Macrophages serve as the primary replicative niche for Legionella. In contrast, dendritic cells (DCs) have been shown to rapidly restrict Legionella infection by activating cell death. The host and bacterial factors that induce this response remain elusive. We found that DCs undergo caspase-dependent cell death and that this response is triggered by a subset of secreted effectors that block host protein synthesis. Specifically, we show that these effectors decrease the levels of pro-survival proteins in DCs, thus leaving cells poised to undergo cell death. Altogether, our data show that pro-survival molecules in DCs serve as guard proteins that detect pathogenic activities to limit bacterial replication.
Supported by a National Science Foundation Graduate Research Fellowship Program (DGE-2236662)
Salmonella enterica serovar Typhimurium is a Gram-negative pathogen that causes diseases ranging from gastroenteritis to systemic infection and sepsis. Salmonella uses type III secretion systems ...(T3SS) to inject effectors into host cells. While these effectors are necessary for bacterial invasion and intracellular survival, intracellular delivery of T3SS products also enables detection of translocated Salmonella ligands by cytosolic immune sensors. Some of these sensors form multimeric complexes called inflammasomes, which activate caspases that lead to interleukin-1 (IL-1) family cytokine release and pyroptosis. In particular, the Salmonella T3SS needle, inner rod, and flagellin proteins activate the NAIP/NLRC4 inflammasome in murine intestinal epithelial cells (IECs), which leads to restriction of bacterial replication and extrusion of infected IECs into the intestinal lumen, thereby preventing systemic dissemination of Salmonella. While these processes are quite well studied in mice, the role of the NAIP/NLRC4 inflammasome in human IECs remains unknown. Unexpectedly, we found the NAIP/NLRC4 inflammasome is dispensable for early inflammasome responses to Salmonella in both human IEC lines and enteroids. Additionally, NLRP3 and the adaptor protein ASC are not required for inflammasome activation in Caco-2 cells. Instead, we observed a necessity for caspase-4 and gasdermin D pore-forming activity in mediating inflammasome responses to Salmonella in Caco-2 cells. These findings suggest that unlike murine IECs, human IECs do not rely on NAIP/NLRC4 or NLRP3/ASC inflammasomes and instead primarily use caspase-4 to mediate inflammasome responses to Salmonella pathogenicity island 1 (SPI-1)-expressing Salmonella.
Extrusion Bioprinting
In article number 2202390, Amir Sheikhi and co‐workers develop a nanoengineered granular bioink (NGB) to enable the extrusion 3D bioprinting of hydrogel microparticle ...(microgel)–based scaffolds with preserved interconnected microporosity. The reversible self‐assembly of heterogeneously charged colloidal nanoplatelets adsorbed onto gelatin methacryloyl microgels enable the extrudability and shape fidelity of NGB at a low packing state without filling the void spaces among the microgels. This work opens new opportunities for the 3D bioprinting of tissue engineered microporous scaffolds beyond the traditional biofabrication window.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
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