MyD88 mediates allergic airway inflammation by regulating ILC2s function through inducing the formation of P38/GATA3...

Allergic asthma stands as the predominant asthma phenotype propelled by aberrant type 2 immune response. Type-2 innate lymphoid cells (ILC2s) are significant for generating IL-5 and IL-13 cytokines, highlighting their vital role in triggering and escalating the progression of asthma. Myeloid differentiation primary response protein 88 (MyD88) controls innate and adaptive immune responses by orchestrating inflammatory signals.

This work focused on investigating the influence of MyD88 in governing ILC2s-driven allergic airway disease alongside its underlying molecular mechanisms.

We evaluated the effects of MyD88 in IL-33-induced or allergen-induced airway hyperreactivity (AHR) and airway inflammation. The role and mechanism of MyD88 in regulating ILC2s function were examined in vivo and in vitro by using transcriptome sequencing analysis, flow cytometry, clinical samples, ILC2-specific MyD88 knockout mice, and anti-Thy1.2 antibody against ILC2s in mice.

The results showed heightened MyD88 expression in ILC2s sourced from allergic asthmatic patients and asthmatic mice. MyD88 knockout in ILC2s was able to mitigate IL-33-induced airway inflammation, while the MyD88 inhibitor LM8 proves efficacious in attenuating allergen-induced airway inflammation and AHR. After elimination of ILC2s via anti-Thy1.2 antibody, the pharmacological activity of LM8 diminished. Mechanistic studies revealed that MyD88 mediates the activation and proliferation of ILC2s through facilitation of P38-GATA3 complex formation.

The research highlights MyD88 as a critical regulator of ILC2s activation, suggesting its potential utility as a therapeutic target for interventions in allergic asthma.