SPL-334

Naïve CD4+ T-cell subset differentiation/polarization is an in vitro assay in which purified naïve CD4+ T cells are activated through TCR and CD28 costimulation and cultured with defined cytokines and neutralizing antibodies to generate Th0, Th1, Th2, Th17, or induced Treg-like populations. Differentiation is detected by subset-associated cytokines and transcription factors: IFN-γ/T-bet for Th1, IL-4/GATA3 for Th2, IL-17A/RORγt for Th17, and Foxp3 for induced Treg cells. The assay readout is usually generated by intracellular cytokine staining after restimulation, transcription-factor staining by flow cytometry, ELISA of secreted cytokines, or gene-expression analysis. The result reflects cytokine-directed lineage commitment or polarization rather than antigen-specific immune protection by itself.

Ovalbumin-induced allergic airway inflammation is a mouse model in which systemic sensitization to ovalbumin, usually with aluminum hydroxide adjuvant, is followed by airway ovalbumin challenge to induce allergic airway inflammation, eosinophil recruitment, mucus production, serum antigen-specific IgE, Th2 cytokine responses, and airway hyperresponsiveness to methacholine. The model is used to study allergen-driven airway inflammation and asthma-like immune responses, but it does not reproduce every feature of human asthma. The main readouts are bronchoalveolar lavage fluid cellularity, lung histopathology, airway hyperresponsiveness, serum OVA-specific IgE, and cytokines such as IL-4, IL-5, and IL-13 in bronchoalveolar lavage fluid or lung samples. Eosinophilia and Th2 cytokines reflect allergic type 2 inflammation, while methacholine responsiveness provides a functional airway-reactivity endpoint.

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