Efficacy of a blocking monoclonal anti-IL-36 receptor (R) antibody in vivo. BALB/c mice (n = 5/group) were pre-treated intranasally (i.n.) with a rat IgG2a anti-mouse IL-36R antibody (M616; 50 μg/mouse; squares), an isotype control antibody (M10; 50 μg/mouse; triangles) or PBS (circles) 2 h prior to i.n. challenge with recombinant IL-36γ (1 μg/mouse) on days 0, 1 and 2. A fourth group of mice, used as negative control, only received i.n. injection of PBS (inverted triangles). On day 2, bronchoalveolar lavage fluids recovered from mice 4 h after the last injection were used to assess (A) total leucocyte and neutrophil counts and (B) chemokine (CCL20, CCL11 and CCL24) protein levels by DuoSet ELISA. (A-B) Results are shown as individual values for each mouse (symbols) and mean values (lines). ***P < 0.001 versus isotype control-treated mice, as assessed by unpaired two-tailed Student's t-test.