CTSB and psoriasis: Although cathepsin B+ MC density was not significantly increased (37.85 (14.42–63.96) vs. 35.21 (13.20–103.8) (Median (IQR)) (Figure 7g), the density of cathepsin B+ MCs did significantly correlate with psoriasis severity (r = 0.74, * p = 0.0225), whereas the total cathepsin B+ cell number did not.