Cladosporium cladosporioides ameliorates visceral hypersensitivity in irritable bowel syndrome-like mice by inhibiting dectin-1 signaling and mast cell activation

Figure 5 Cladosporium cladosporioides suppresses mast cell activation by inhibiting dectin-1/nuclear factor kappa B signaling. A: Cell counting kit 8 assay of mast cell viability following coculture with Cladosporium cladosporioides (C. cladosporioides) at different multiplicities of infection (MOIs) for 48 hours. n = 6, one outlier identified and removed with Turkey outlier analysis in MOI 5; B: Mast cell degranulation detected using β-hexosaminidase releasing assay after treatment at different MOIs for 2 hours; C: Interleukin 1 beta (IL-1β) and tumor necrosis factor alpha (TNF-α) mRNA expression in mast cells detected using reverse transcription-quantitative polymerase chain reaction after treatment at different MOIs for 12 hours; D: IL-1β and TNF-α expression in mast cells detected using enzyme-linked immunosorbent assay after treatment at different MOIs for 24 hours; E: Dectin-1/nuclear factor kappa B expression in mast cells stimulated with curdlan (350 μg/mL) and cocultured with C. cladosporioides at different MOIs for 24 hours; F: Quantification of dectin-1 protein levels normalized to β-actin levels, and p-p65 levels normalized to p65 levels; G: IL-1β and TNF-α expression detected using enzyme-linked immunosorbent assay after treatment with curdlan and C. cladosporioides at different MOIs for 24 hours. Data are presented as the mean ± SD. One-way ANOVA followed by Tukey’s test and Student’s t-test (n = 3). ^aP < 0.05, ^bP < 0.01, ^cP < 0.001 compared to the vehicle group; ^dP < 0.05, ^eP < 0.01, ^fP < 0.001 compared to the curdlan 350 μg/mL group. MOI: Multiplicity of infection; Iono: Ionomycin; Cur 350: Curdlan 350 μg/mL; TNF: Tumor necrosis factor; IL: Interleukin.