Figure 1.

Mefloquine and siramesine reduce the number of mast cells in human lung tissues. Human lung specimens were incubated in media containing 20 µM of mefloquine, siramesine, or phosphate-buffered saline (PBS; as vehicle) for 24 h. Cross sections of the lung specimens were then prepared and immunostained for tryptase followed by nuclear counterstaining with Mayer’s hematoxylin to evaluate the number of lung mast cells. (A) Quantification of the number of lung tryptase⁺ mast cells (n = 5–10; representative of two independent experiments/two donors). The graphs show mean ± SEM (****P < 0.0001). (B) Representative images of lung sections showing the reduction in the number of tryptase⁺ mast cells (arrows) in the presence of mefloquine or siramesine.