TRAF6 and IRAK-1 expression levels are similar between RA patients, healthy controls, and disease controls. RNA was isolated from PBMCs from healthy control individuals (n = 9), disease control individuals (n = 4) and RA patients (n = 14), and mRNA expression levels of (a) TRAF6 and (b) IRAK-1 were analyzed using qRT-PCR. (c) PBMCs isolated from a healthy control individual and RA patient were incubated on glass slides for 1 hour at 37°C. The adhered cells were fixed and permeabilized in 3% paraformaldehyde and 0.5% Triton X-100, respectively. Protein levels of TRAF6 and IRAK-1 were analyzed by immunofluorescence using rabbit anti-TRAF6 and anti-IRAK-1 antibodies, and relative fluorescence was determined using Image J analysis software. SEM is shown; n > 20 cells. IRAK, IL-1 receptor-associated kinase; PBMC, peripheral blood mononuclear cell; qRT-PCR, quantitative real-time RT-PCR; RA, rheumatoid arthritis; RT-PCR, reverse transcription polymerase chain reaction; SEM, standard error of the mean; TRAF, tumor necrosis factor receptor-associated factor.