Cytotoxicity and immunotoxicity of cyclopiazonic acid on human cells

•Cyclopiazonic acid is cytotoxic on human monocytes and CD34 cells.•Cyclopiazonic is cytoxic on THP1 and Caco cells.•Cyclopiazonic inhibits macrophages differentiation at no cytotoxic concentrations. In this study, in vitro cytotoxicity and immunotoxicity of the mycotoxin cyclopiazonic acid (CPA) was evaluated on human cells. To evaluate cytoxicity, several cellular targets were used (CD34+, monocytes, THP-1 and Caco-2). Monocytes were more sensitive to CPA than the THP-1 monocytic cell line after 48h of incubation in the tested conditions. Half maximal inhibitory concentration (IC50) were determined to be 8.5×10−8 and 1.75×10−7M for monocytes and THP1, respectively, while IC50>1.25×10−7M was observed for Caco-2 and CD34+ cells. The CPA effect on macrophage differentiation was also examined at non-cytotoxic concentrations. The monocyte differentiation process was markedly disturbed in the presence of CPA. After 6days of culture, CD71 expression was downregulated, while CD14 and CD11a expressions did not change. Moreover, activated macrophages showed a raised burst activity and TNF-α secretion. Overall, the results indicated that CPA exhibited toxicity on various human cellular models. Moreover, at non-cytotoxic concentrations, CPA disturbed human monocytes differentiation into macrophages. This work contributes to understanding the immunosuppressive properties of this food-related toxin.