T helper type 2 cytokine signaling (Th2 signaling)

T helper type 2 (Th2) cytokine signaling is a fundamental immunological pathway driven by Th2 cells and their characteristic cytokines, primarily interleukin-4 (IL-4), IL-5, and IL-13 [1.2.1, 1.2.2]. This signaling axis plays a critical role in the body's defense against helminthic parasites and the regulation of humoral immunity, including B cell isotype switching to IgE [1.2.3, 1.2.4]. When overactive or dysregulated, this pathway leads to Type 2 (T2) inflammation, which is the underlying cause of several chronic allergic and atopic conditions such as asthma, atopic dermatitis, and chronic rhinosinusitis with nasal polyps [1.3.2, 1.4.1]. Modern therapeutic interventions target various nodes of this pathway, including monoclonal antibodies that neutralize specific cytokines or block their receptors, and small molecules that inhibit downstream Janus kinase (JAK) signaling [1.3.2, 1.4.2]. These treatments have revolutionized the management of T2-high diseases by significantly reducing exacerbations and improving patient quality of life [1.1.2, 1.4.3].

Other names

Type 2 cytokine signalingTh2 axisType 2 inflammation pathwayT2 signaling

Drugs targeting this pathway function by neutralizing key effector cytokines (such as IL-4, IL-5, IL-13, or TSLP) or blocking their respective cell-surface receptors to prevent downstream signal transduction through the JAK-STAT pathway, thereby inhibiting the activation of Th2-specific transcription factors like GATA3 and STAT6 [1.2.2, 1.3.2, 1.4.5].