Blocking CD226 regulates ILC2 effector function and alleviates airway hyperreactivity

Type 2 innate lymphoid cells (ILC2s) play a pivotal role in type 2 asthma. CD226 is a costimulatory molecule involved in various inflammatory diseases. Here, we aimed to investigate CD226 expression and function within human and mouse ILC2s, and to assess the impact of targeting CD226 on ILC2-mediated airway hyperreactivity (AHR). Our findings demonstrated an inducible expression of CD226 in activated ILC2s, enhancing their cytokine secretion and effector functions. Blocking CD226 ameliorates ILC2-dependent AHR in IL-33 and Alternaria Alternata-induced models. Interestingly, CD226 is expressed and inducible in human ILC2s, and its blocking reduces cytokine production. Finally, we showed that peripheral ILC2s in asthmatic patients exhibited elevated CD226 expression compared to healthy controls.Our findings underscore the potential of CD226 as a novel therapeutic target in ILC2s, presenting a promising avenue for ameliorating AHR and allergic asthma. mRNA profiles of mouse lung ILC2s from WT mice that were treated with isotype control or anti-CD226 antibody were generated by deep sequencing, in duplicates, using a NextSeq 500.