Figure 1: Cockroach allergen extracts activate store-operated CRAC channels in BEAS-2B cells.

(A–C) [Ca²⁺_i] imaging showing responses of individual BEAS-2B cells to cockroach allergen extracts (10 μg/mL) administered in (A) 2 mM Ca²⁺ ringer’s solution, (B) Ca²⁺ free ringer’s solution or (C) 2 mM Ca²⁺ ringer’s solution in the presence of the CRAC channel inhibitor BTP2 (500 nM). (D) Average [Ca²⁺_i] response of the individual cells shown in (A–C). (E–F) Summary of the average rise in [Ca²⁺_i] 600 seconds after addition of cockroach extract (E) and the integral of the [Ca²⁺]_i signal during application of the allergen. (F). (G) Ca²⁺ imaging trace showing SOCE in BAES-2B cells. SOCE was induced by depleting ER Ca²⁺ stores with 1 µM thapsigargin in a Ca²⁺-free Ringer’s solution and readding 2 mM Ca²⁺ following store depletion. Pre-treating cells with BTP2 (500 nM) strongly inhibits SOCE. (H) Summary of average rise in cytosolic Ca²⁺ levels 200 seconds after re-addition of 2 mM Ca²⁺ ringer’s following store-depletion. Data are mean ± SEM of 34-47 cells. Representative of 5 independent experiments. **P < 0.01, ***P < 0.001, Ck. Ext, cockroach extract.