Expression profiles of immune-related genes in coelomocytes during regeneration after evisceration in Apostichopus japonicus

A representative echinoderm, the sea cucumber Apostichopus japonicus has a special regeneration mechanism. The sea cucumber has no specific immune tissues or organs. Coelomocytes of sea cucumbers are involved in their cellular and humoral immunity. In this study, expression profiles of the main immune-related factors in sea cucumber coelomocytes were detected during coelomocyte regeneration after evisceration in A. japonicus. Immune-related factors Cu/Zn superoxide dismutase (Cu/Zn SOD), Catalase (CAT), C-type lysozyme (C-LYZ), Cathepsin D (CTSD), Melanotransferrin (MTF), Toll-like receptor (TLR), C-type lectin (C-LCT), Complement 3 (C3), Myeloid differentiation factor 88 (MYD88), Nuclear factor kappa-B (NF-κB), NF-κB inhibitor (IKB), TNF receptor-associated factor 6 (TRAF6), Peroxiredoxins (PRX), Nitric oxide synthase(NOS), Caspase-2 (CASP-2), Phenoloxidase (PO), and Glutathione Peroxidase(GPX), Heat shock protein 70 (HSP70) were detected by real-time fluorescent quantitative PCR at different time points during regeneration. The main immune-related genes in sea cucumber coelomocytes were significantly differentially expressed after evisceration, and an upregulation was observed for the majority of the considered genes. In summary, the discharge of viscera had a significant effect on expression of immune-related genes of sea cucumber coelomocytes. The expression level of each gene had a certain correlation with the sea cucumber regeneration process. The results provide reference data for the immune response of coelomocytes during regeneration.