Knockdown of TRAF6 and/or IRAK-1 results in decreased TNF-α production in THP-1 cells. THP-1 cells were transfected with siRNA targeting TRAF6 and/or IRAK-1. (a) 48 hours after transfection, mRNA levels of TRAF6 and IRAK-1 were analyzed by qRT-PCR and normalized to mock transfected cells. SEM shown (n = 2). After knockdown of TRAF6 and/or IRAK-1 was confirmed by qRT-PCR, cells were treated with 1 μg/ml LPS for 24 hours and culture supernatants were collected. Multiplex assay was used to quantitatively detect (b) TNF-α and (c) MCP-1. IRAK, IL-1 receptor-associated kinase; LPS, lipopolysaccharide; MCP, macrophage chemoattractant protein; PBMC, peripheral blood mononuclear cell; qRT-PCR, quantitative real-time RT-PCR; RT-PCR, reverse transcription polymerase chain reaction; TNF, tumor necrosis factor; TRAF, tumor necrosis factor receptor-associated factor.