FLEX station measurement of intracellular calcium with PTC in TR146 MUC1 cells with and without UWS from older and younger adults. TR146 MUC1 Cells were loaded with the fluo-4am calcium indicator and incubated with or without UWS from older (60+ years, n = 22) and younger (18–30 years, n = 29) adults. Florescence emissions were recorded using FLEX station fluorescence plate reader, before and after addition of 25 µM TC. (A) Mean (+/−SEM) change (∆) in fluorescence from baseline after compound addition (normalised to ionomycin response and control WS response), in TAS2R38:Ga16Gust44 co-transfected TR146 MUC1 cells. Cells stimulated with 25 µM PTC without WS used for comparison (n = 44). Data is representative of two experiments. (B) Transfection efficiency of TR146 MUC1 cells, without whole mouth saliva (WS). Mean (+/−SEM) change (∆) in fluorescence from baseline after compound addition, in mock transfected (MT) and TAS2R38:Ga16Gust44 co-transfected (T:G) TR146 MUC1 cells (n = 20). Analysed for statistical significance using independent student’s t test. Significance = p value < 0.05 * p < 0.01 ** p < 0.001 ***.