Chondroitin sulfate

Apoptosis, also called programmed cell death, is generally characterized by distinct morphological characteristics.

Lipopolysaccharide (LPS)-induced endotoxemia is a widely used in vivo model of acute systemic inflammation in which LPS, a Gram-negative bacterial endotoxin, activates innate immune signaling primarily through TLR4, leading to rapid and transient induction of pro-inflammatory cytokines such as TNF-α, IL-6, and IL-1β in circulation and tissues. This cytokine surge is commonly used as a measurable readout of systemic inflammatory activation and immune dysregulation, and is typically assessed within hours after intraperitoneal LPS administration in mouse models of endotoxemia. The model captures key features of systemic inflammatory response syndrome, including cytokine release, immune cell activation, and downstream tissue responses, and has been used to evaluate anti-inflammatory interventions such as cytokine modulation, lipid mediators, and immune cell-targeting therapies.

Apoptosis is a regulated, generally non-lytic cell-death pathway that removes unwanted, damaged, infected, or abnormal cells through coordinated morphological changes, caspase activation, DNA fragmentation, and membrane remodeling. The intrinsic apoptosis pathway is controlled mainly by mitochondrial outer membrane permeabilization, BCL-2 family proteins, cytochrome c release, apoptosome formation, caspase-9 activation, and downstream executioner caspase-3/7 activation. The extrinsic apoptosis pathway is initiated by death receptors such as Fas, TNFR, and TRAIL receptors, which recruit adaptor proteins and activate caspase-8 before engaging executioner caspases or mitochondrial amplification through BID cleavage. Apoptosis is linked to many phenotypes, including cancer cell killing, tissue homeostasis, immune regulation, neurodegeneration, infection response, and treatment-induced cytotoxicity; unresolved questions include how apoptosis interacts with necroptosis, pyroptosis, ferroptos

The NLRP3 inflammasome is a cytosolic innate immune signaling platform that integrates priming signals and danger-signal activation to promote caspase-1 activation, maturation of IL-1β and IL-18, and gasdermin D-mediated pyroptotic cell death. The core experimental logic is to determine whether inflammatory disease phenotypes are driven by increased NLRP3 expression, ASC-containing inflammasome assembly, caspase-1 cleavage, GSDMD cleavage, and extracellular release of IL-1β/IL-18 rather than by nonspecific cell injury alone. The pathway is strongly linked to inflammation-related disease phenotypes because monosodium urate crystals activate NALP3/NLRP3 inflammasome signaling in gout-like crystal inflammation, cholesterol crystals activate NLRP3 inflammasomes in atherogenesis models, and DSS-induced intestinal inflammation has been reported to involve NLRP3 inflammasome activity. However, experimental colitis studies also show context-dependent protective effects of NLRP3 inflammasome co

Recombinant protein expression in Escherichia coli followed by purification of a His-tagged soluble protein by immobilized metal affinity chromatography (IMAC), with optional MBP fusion and TEV tag removal when the construct includes these elements. The biological readout is production of the encoded target protein, detected as an inducible band at the expected molecular mass by SDS-PAGE and quantified by total protein assay or chromatographic absorbance; the purification readout is enrichment of the target protein in elution fractions after selective binding of polyhistidine residues to immobilized Ni2+/metal-chelate resin and elution by imidazole-containing buffer. Expression is driven by an inducible bacterial expression system, commonly T7/lac-based, in which IPTG or lactose/auto-induction activates transcription and translation of the cloned gene; lower induction temperature, lower inducer concentration, induction timing, and solubility-enhancing fusion tags can influence the frac