['Although the mechanism of asthma is not precisely understood in humans, clinical and epidemiological studies have offered a potential relationship between exposure to environmental fungi, such as Alternaria alternata (A. alternata) and the development and exacerbation of asthma. The aim of this project is to investigate the mechanisms of Th2 responses by A. alternata as a clinically relevant model for the environmental exposure.', 'Plastic adherent monocytes were cultured with granulocyte macrophage colony stimulating factor (GM-CSF) and interleukin-4 (IL-4) to convert these cells into Monocyte-derived Dendritic cells (MoDc) and then matured in the presence of Monocyte-Conditioned Medium (MCM) as the control group and MCM+ A. alternata extract as the inductive groups.', 'The results indicated that the expression of CD14 decreased and CD83 and anti-human leukocyte antigen-DR (HLA-DR) increased in the inductive groups in comparison with the control group. More importantly, A. alternata inhibited IL-12 production by activated dendritic cells (DCs), and the DCs exposed to A. alternata enhanced the Th2 polarisation of CD4'] Does alternaria alternata act on human Monocyte-derived Dendritic cells to mediate Th2/Th17 polarisation?