The effect of tasquinimod on granuloma formation. The effect of tasquinimod (TasQ) on granuloma formation was evaluated using the guinea pig granuloma model. (A) Lung sections derived from TasQ-treated (right panel) and mock-treated (left panel) guinea pigs were stained with hematoxylin and eosin, and representative micrographs obtained from 2 independent experiments are shown. Scale bars, 1 mm. (B) Granulomas with a diameter of >200 μm were counted for 3 animals in each group. Numbers of granulomas per section are shown as the mean ± standard error of the mean. *P < .01. (C) Lung sections derived from TasQ-treated and mock-treated guinea pigs were labeled with G213 mAb, and HRP-DAB-based detection was performed. Representative micrographs obtained from 2 independent experiments are presented with granulomas containing the central accumulation of S100A9⁺ neutrophils indicated with arrows. Scale bars, 500 μm. (D) Granulomas with S100A9⁺ neutrophil cores were counted per section for 3 animals in each group, and data are shown as the mean ± standard error of the mean. *P < .01.