Fig. S4. Release of ATP from MCC13 cells by mechanical membrane deformation.

Fig. S4. Release of ATP from MCC13 cells by mechanical membrane deformation. To mimic mechanical membrane deformation, cells were treated with chlorpromazine (CPZ), a mechanomimetic agent that induces membrane curvature. ATP concentrations in the conditioned media of MCC13 cells treated with chlorpromazine (CPZ; 10–100 μM) in the absence (grey bars) or presence (yellow bars) of gadolinium (Gd³⁺), a non-selective mechanosensitive ion channel blocker. Extracellular ATP was quantified using a luciferase-based ATP ELISA assay. Each dot represents data from an independent sample (n = 10 for grey bars; n = 8 for yellow bars). Statistical analysis was performed using Welch’s ANOVA followed by Dunnett’s T3 post-hoc test (grey bars vs. vehicle), and Mann–Whitney or unpaired t-tests (grey vs. yellow bars). Data are presented as mean ± SEM. **P < 0.01 and ***P < 0.001 vs. vehicle for grey bars; ##P < 0.01 and ###P < 0.001 vs. CPZ (grey bar) at the same concentration.Supplementary figure associated with: Seo MS et al. Merkel cells release ATP in response to mechanical stimulation to mediate paracrine signalling. British Journal of Dermatology (2026). https://doi.org/10.1093/bjd/ljag067