TPT-260

Western blotting (WB) is a commonly used experimental method in molecular biology, biochemistry, and immunogenetics for identifying and quantifying target proteins. It combines gel electrophoresis with immunoassay, enabling researchers to analyze protein expression, post-translational modifications, and molecular weight.

Live/dead viability and cytotoxicity staining assays are based on the simultaneous detection of intracellular esterase activity in metabolically active (viable) cells and membrane integrity loss in non-viable cells. In commonly used dual-staining approaches, membrane-permeant fluorogenic substrates are converted by intracellular esterases into fluorescent products in live cells, while impermeant DNA-binding dyes selectively enter cells with compromised plasma membranes and label nucleic acids in dead or dying cells, enabling discrimination between viable and non-viable populations by fluorescence microscopy or flow cytometry.

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

Congo red amyloid staining is a histochemical method used to detect extracellular amyloid deposits in tissue sections based on the affinity of Congo red dye for β-pleated sheet-rich protein aggregates. When bound to amyloid, Congo red produces characteristic apple-green birefringence under polarized light microscopy, which is widely regarded as a diagnostic feature of amyloid deposition in histopathology. The diagnostic principle relies on the combination of dye binding (congophilia) and optical anisotropy under polarized illumination, which distinguishes amyloid from most non-amyloid eosinophilic extracellular deposits in routine histological evaluation. Amyloid identification by Congo red staining remains a cornerstone in diagnostic pathology despite the availability of adjunct methods such as immunohistochemistry and mass spectrometry, particularly because of its ability to localize deposits directly within tissue architecture. The specificity of Congo red-positive deposits is incre

The following protocol uses the MTT colorimetric assay as a classic literature-established method for assessing cell viability/metabolic activity in cultured mammalian cells. MTT[3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] is reduced by metabolically active cells to a colored formazan product; the amount of formazan is quantified spectrophotometrically and provides an indirect measure of metabolically active viable cells. Importantly, MTT reduction reflects cellular oxidoreductase/metabolic activity rather than an absolute direct count of living cells, so changes in cellular metabolism can alter the signal independently of cell number.

Alzheimer’s Disease (AD) is a neurodegenerative disorder characterized by a progressive decline in cognitive functions and loss of specific types of neurons and synapses. Alzheimer's symptoms can be simulated in mice by injecting drugs (such as Aβ) or genetically modified.

Kinase activity assays measure the ability of kinases to transfer phosphate groups from ATP to specific substrates, while phosphorylation assays detect the presence and levels of phosphorylated proteins. Common methods include radiolabeled ATP incorporation (e. g. ,), ADP release detection via bioluminescence (e. g. ,[3]), enzyme-linked immunosorbent assays (ELISA) for phospho-specific epitopes (e. g. ,[6]), and microtiter-based formats for high-throughput screening (e. g. ,[8]). The ADP-Glo assay quantifies kinase activity by measuring ADP produced during phosphorylation using a luciferase-based system. Radiometric assays involve autoradiography or scintillation counting after incorporation of ³²P-labeled ATP into substrate proteins. ELISA-based approaches rely on phospho-specific antibodies to detect activated kinases in cell lysates or purified samples.

Cytoplasmic-nuclear fractionated protein extraction separates soluble cytoplasmic proteins from nuclear-enriched proteins by mild plasma-membrane permeabilization, differential centrifugation, washing of nuclei, and extraction of nuclear proteins for downstream immunoblotting or related molecular analysis. The readout is the relative abundance of a protein in cytoplasmic and nuclear fractions, commonly assessed by western blotting together with compartment markers such as tubulin or pyruvate kinase for cytoplasm and lamin, nucleoporin, hnRNP, H2AX, or Lamin B for nuclear fractions.

Cytotoxicity assays are usually based on the assessment of cell membrane damage, which can also be indirectly detected by measuring cell viability. Detection methods include MTT assay, CKK-8 assay, LDH assay and ATP assay, etc.

Dextran sulfate sodium (DSS)-induced colitis is generated by administering DSS in mouse drinking water, producing epithelial injury, barrier disruption, weight loss, diarrhea, fecal blood, colon shortening, histologic mucosal damage, and inflammatory mediator changes; the model is mainly used to study acute or chronic intestinal inflammation resembling selected features of ulcerative colitis. DSS injury is interpreted through clinical and tissue readouts rather than a single molecular endpoint: daily body weight, stool consistency, and bleeding are combined into a disease activity index, while colon length, histology, cytokines, myeloperoxidase activity, intestinal permeability, and tight-junction markers provide complementary measures of inflammation and barrier damage.

TNBS-induced colitis is produced by intrarectal delivery of 2,4,6-trinitrobenzene sulfonic acid in ethanol, where ethanol disrupts the mucosal barrier and TNBS haptenates colonic proteins, generating immune-mediated colonic inflammation with weight loss, diarrhea, ulceration, transmural injury, inflammatory-cell infiltration, and cytokine responses. The model is used as an experimental intestinal inflammation model with Crohn’s disease–like features, especially when Th1-type responses, IL-12–dependent inflammation, chronic relapsing inflammation, or fibrosis-related endpoints are studied.

Kinase activity assays measure transfer of phosphate from ATP to a protein or peptide substrate, generating phosphorylated substrate, ADP, or incorporated radiolabeled phosphate as the readout; phosphorylation assays measure site-specific phosphorylation in cells or tissues as a proxy for kinase-pathway activation, inhibition, or substrate regulation. Phosphorylation can be detected by phospho-specific Western blot, immunoprecipitation kinase assay, phospho-immunofluorescence, phospho-flow cytometry, luminescent ADP detection, radiolabeled ATP incorporation, or reporter-based pathway assays, and these readouts can be applied to cancer cells, primary neurons, mouse tumors, organoids, inflammatory macrophages, ferroptosis studies, and mitophagy studies when the kinase target is biologically relevant.

Pyroptosis is a lytic inflammatory cell-death pathway executed by gasdermin pores, most classically through inflammasome-mediated activation of caspase-1, cleavage of gasdermin D, membrane pore formation, LDH release, and secretion of IL-1β and IL-18. The canonical pathway is commonly modeled by priming cells with an inflammatory signal such as LPS to induce pro-IL-1β and inflammasome components, followed by an activation signal such as ATP or nigericin to activate NLRP3, ASC speck formation, caspase-1 cleavage, GSDMD cleavage, cytokine release, and pyroptotic membrane rupture. The non-canonical pathway is triggered when cytosolic LPS activates mouse caspase-11 or human caspase-4/5, leading to GSDMD cleavage and pyroptosis, and this can secondarily activate NLRP3-dependent IL-1β release. Pyroptosis is linked to inflammatory injury, infection, cancer, liver disease, ocular disease, placental inflammation, and other disease phenotypes, but unresolved questions include which gasdermin fam