Expression of immunomodulatory genes in human monocytes induced by voriconazole in the presence of Aspergillus fumigatus

Abstract

We assessed the effect of voriconazole (VRC) on the expression and release of selected cytokines and chemokines in the THP-1 human monocytic cell line in response to Aspergillus fumigatus hyphal fragments (HF) by cDNA microarray analysis, reverse transcriptase (RT) PCR, and enzyme-linked immunosorbent assay. Stimulation of THP-1 cells by HF alone caused a significant up-regulation of CCL4 (MIP1B) and CCL16, while CCL2 (MCP1) was down-regulated. By comparison, in the presence of VRC, a large number of genes such as CCL3 (MIP1A), CCL4 (MIP1B), CCL5 (RANTES), CCL7 (MCP3), CCL11 (EOTAXIN), CCL15 (MIP1Delta), CXCL6, and CXCL13 were strongly up-regulated in THP-1 cells challenged by HF, whereas CCL20 (MIP3A) and CCL21 (MIP2) were down-regulated. Among five genes differentially expressed in THP-1 cells, IL12A, IL12B, and IL-16 were down-regulated whereas IL-11 and TGFB1 were significantly up-regulated in the presence of VRC. The inflammation-related genes IFNgamma, IL1R1, and TNFA were also up-regulated in THP-1 cells exposed to HF only in the presence of VRC. RT-PCR of four selected genes validated the results of microarrays. The release of interleukin 1beta (IL-1beta) and IL-12 was significantly increased from monocytes stimulated either by HF alone (P < 0.05) or in the presence of VRC (P < 0.01 and P < 0.05, respectively). In contrast, tumor necrosis factor alpha release from monocytes was enhanced only in the presence of VRC (P < 0.01). The chemokines monocyte chemoattractant protein 1 and macrophage inflammatory protein 1beta were decreased under both conditions (P < 0.01). These results demonstrate that in the presence of VRC, HF induces a more pronounced profile of gene expression in THP-1 cells than HF alone, potentially leading to more-efficient host resistance to A. fumigatus.

FIG. 1.

Profiles of IL-1β (A), MCP-1 (B), MIP-1β (C), TNF-α (D), and IL-12 (E) cytokine levels released after incubation of THP-1 cells (MNC) alone (dark columns), with A. fumigatus HF without VRC (MNC+HF) (horizontally striped columns), or in the presence of 0.1 μg/ml VRC (MNC+HF+VRC) (vertically striped columns) at 37°C for 6 h. Data are presented as means ± standard errors of the means derived from five donors/experiments. Comparisons between treated and control cells were performed using analysis of variance with Dunnett's test for multiple comparisons. Cells with P values of <0.05 are indicated by asterisks, and those with P values of <0.01 are indicated by daggers (†).