Figure 2.

Gene expression in skin analyzed with qPCR (individual samples). Data are -ΔΔCt ± SD (n = 6). A. collagen (COL) genes: COL1a, COL2a and COL10a B. components of the extracellular matrix (ECM): decorin (DCN), elastin (ELN) and laminin (LMN) C. 5-aminolevulinate synthase (ALAS2), alkaline phosphatase (ALP) and regulatory bone morphogenic protein (BMP4) D. proteases involved in ECM remodelling, matrix metalloproteinases (MMP) 9 and 13 and in antigen presentation, cathepsin S (CTSS) E. beta-2-microglobulin-2 JB1 (B2M), a component of the major histocompatibility complex (MHC) class I; MHC class II α chain (MHCIIa) and regulator of inflammation prostaglandine D synthase (PGDS) F. T cell-inhibitory programmed death ligand 1 (PD-L1), CD4, marker of T cells and IL-1 receptor type 1 (IL1RI), transducer of pro-inflammatory signals G. CD8α, expressed on cytotoxic T cells; IL-12β, produced in Th1 settings and ARG1, marker of the Th2 response H. CCAAT/enhancer-binding protein β (C/EBPb) involved in the control of cell proliferation and differentiation; regulatory cytokines IL-10 and transforming growth factor-β (TGF-β). Significant difference from uninfected control (t-test, p < 0.05) is indicated with *. I-intact skin of infected fish, D-skin damaged by sea lice