TLR4 and psoriasis: Meanwhile, this was the case for 16 of the itch-associated genes in MCs isolated from psoriasis skin, including CTSB, TLR4, and TACR1 (training set AUC OOB = 1, OOB Error rate = 11.11%, validation set AUC = 0.875, 95% CI = 0.63–1; Figure 7b).