ERS increased the mRNA levels of the ERS markers in imDCs. (a,b) The mRNA levels of SELENOK and SELENOS, as well as (c–f) the ERS markers ATF4, ATF6, BIP and CHOP in imDCs after treatment with Tm, were assayed by RT-PCR (n = 3). * p < 0.05, ** p < 0.01, *** p < 0.001 and **** p < 0.0001 were compared with DMSO-treated imDCs. ERS, endoplasmic reticulum stress; imDCs, immature dendritic cells; SELENOK, selenoprotein K; SELENOS, selenoprotein S; ATF4, activating transcription factor 4; ATF6, activating transcription factor 6; BIP, binding immunoglobulin protein; CHOP, C/EBP homologous protein; Tm, tunicamycin; DMSO, dimethyl sulfoxide.