Relative quantification of studied gene expressions in SPTL lesions compared with reference tissue (erythema nodosum). Relative mRNA expression of CXCR3 (white column), IDO-1 (dark grey), and IFNG (light grey) in SPTL lesions. Relative expressions are represented as fold changes in comparison with erythema nodosum. To note, CXCR3 and IFNG genes showed no detectable expression in case 5, although the GAPDH level was similar to other samples. All gene expression levels were normalized to reference gene, GAPDH. nd = not detected.