Fig. 5: Human ILC2s express CD52, and Alemtuzumab ameliorates human ILC2-mediated AHR.

Human peripheral blood ILC2s were freshly sorted (n = 6 donors) and cultured with 10 ng of recombinant human (rh)-IL-2 and rh-IL-7 in the presence or absence of rh-IL-33 (10 ng). CD52 mRNA expression levels were analyzed after 9 h and CD52 protein expression levels were analyzed after 48 h. a The gating strategy of human ILC2s identified as Lin^–CD45⁺CD127⁺CRTH2⁺ cells. b, c Expression levels of CD52 at a mRNA and protein levels in both naïve (PBS) and IL-33-activated human ILC2s. Corresponding quantitation of CD52 expression shown as MFI ± SEM, n = 6. d Human peripheral ILC2s (n = 6 donors) were purified via FACS and cultured with recombinant human (rh)-IL-2 (20 ng/ml) and rh-IL-7 (20 ng/ml) for 48 h, and then adoptively transferred into Rag2^−/−Il2rg^−/− mice that were treated with 250 µg of Alemtuzumab i.p. or isotype control on day 1. In addition, mice were challenged with either rh-IL-33 (1 µg) or PBS intranasally (i.n.) on days 2, 3, and 4. Measurement of lung function and analysis of BAL followed on day 5, as shown in the timeline. e, f Line graphs show lung resistance and dynamic compliance (cDyn) in response to increasing doses of methacholine. g The numbers of eosinophils in the BAL. h The numbers of human ILC2s in the lungs. Data are shown as means ± SEMs and are representative of three individual experiments. Statistical analysis, two-tailed Student’s t-test or one-way ANOVA followed by Tukey post-hoc tests. *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001, and n.s. non-significant. Human, mouse, and lung images are provided with permission from Servier Medical Art.