Combined cytokine expression in acral and nonacral samples. (a) Two-dimensional scatter plot of IL17A and IL13 composite expression in the entire tissue specimen of acral and nonacral samples. (b) Two-dimensional scatter plot of IFNG and IL13 composite expression in acral and nonacral samples. (c) Three-dimensional scatter plot of IFNG, IL13, and IL17A composite expression in acral and nonacral samples. HPE (n = 12), NAE (n = 9), PP (n = 8), NAP (n = 8), and MFPP (n = 8). Each point represents an individual case. Circles represent acral samples, and diamonds represent nonacral samples (A and B). Cytokine composite expression was normalized to tissue area in mm2. Axes are log2 (1 + cytokine composite expression/mm2). Polygons indicate the boundaries of cytokine expression for a given group. HPE, hyperkeratotic palmoplantar eczema; MFPP, mycosis fungoides palmaris et plantaris; NAE, nonacral eczema; NAP, nonacral psoriasis; NL, normal acral skin; PP, palmoplantar psoriasis.