Figure 3.

Basolateral PAR-2 stimulation activates Ca²⁺ signaling in primary sinonasal ALI cultures. A) Schematic of primary ALI culture. B) Apical trypsin (tryp.) or thrombin (throm.) had no effect on Ca²⁺ signaling, whereas basolateral trypsin activated a Ca²⁺ increase (n = 4 cultures from 4 individual patients) C) Basolateral thrombin had no effect, whereas basolateral trypsin activated a Ca²⁺ increase (n = 4 cultures from 4 individual patients). D) 2FLI activated Ca²⁺ responses in sinonasal ALIs. E) TLR priming [24–48 h stimulation with 2 µg/ml LPS, lipoteichoic acid (LTA), FSL-1, and 5 µg/ml polyI:C] had no effect on 2FLI-induced Ca²⁺ responses. F) Peak [Ca²⁺]_i responses were not different in ALIs derived from turbinate or ethmoid sinus (left) or control vs. patients with CRS (right; ALIs from 3 individual samples for each type compared). N.s., not significant. G) Responses observed with 2FLI were greater than those observed with saturating (100 µM) histamine. H) Primary ALI cultures loaded with rhod-2 exhibited punctate mitochondrial fluorescence pattern. I, J) Basolateral 20 µM 2FLI, but not 100 µM histamine, caused an increase in rhod2 fluorescence, suggesting apical mitochondrial Ca²⁺ uptake.