Cryptococcus neoformans Secretes Small Molecules That Inhibit IL-1β Inflammasome-Dependent Secretion

Figure 3

1 kDa CM35 inhibits caspase-1 activation, promotes pro-IL-1β accumulation, and inhibits cell death. (a) LDH release from supernatants of BMMs stimulated with LPS (500 ng/ml) and/or nigericin (20 μM), with or without inhibitors (10% ). The medium group was utilized as negative control (0% of cell death) and the DMSO (15%) group was used as positive control (100% of cell death). (b) pro-IL-1β production measured from cell lysates of BMMs stimulated with LPS (500 ng/ml) and/or nigericin (20 μM), with or without inhibitors (10% ). (c–f) BMMs stimulated with LPS (500 ng/ml) and nigericin (20 μM) or Δcap67 (MOI 5 : 1), with or without inhibitors, were analyzed for caspase-1 activation (FLICA). LDH release was measured by colorimetric assay (a), cytokine was measured by ELISA (b), and caspase activation was measured by flow cytometry. (c, d) LPS and nigericin or (e, f) Cap67 was used as stimuli, and the mean fluorescence intensity (MFI) was assessed (d, f). Statistical analysis was performed by one-way ANOVA, where ns: not significant; ; ; . Comparisons were made with the LPS only group (a, b).

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