Raudstein Mari, Peñaranda Ma Michelle D, Kjærner-Semb Erik, Grove Søren, Morton H Craig, Edvardsen Rolf Brudvik
Institute of Marine Research, Bergen, Norway.
Sci Rep. 2025 Jan 28;15(1):3599. doi: 10.1038/s41598-025-87658-5.
Infectious diseases pose significant challenges to Norwegian Atlantic salmon aquaculture. Vaccines are critical for disease prevention; however, a deeper understanding of the immune system is essential to improve vaccine efficacy. Immunoglobulin M (IgM) is the main antibody involved in the systemic immune response of teleosts, including Atlantic salmon. In this study, we used CRISPR/Cas9 technology to knock out the two IgM genes in Atlantic salmon. High-throughput sequencing revealed an average mutagenesis efficiency of 97% across both loci, with a predominance of frameshift mutations (78%). Gene expression analyses demonstrated significantly reduced membrane-bound IgM mRNA levels in head kidney and spleen tissues. Flow cytometry revealed a 78% reduction in IgM B cells in peripheral blood, and Western blot analyses showed decreased IgM protein levels in serum. Notably, an upregulation of IgT mRNA was observed, suggesting a potential compensatory mechanism. This work presents the first application of CRISPR/Cas9 to disrupt an immune-related gene in the F0 generation of Atlantic salmon, and lays the foundation for generating a model completely lacking IgM B cells which can be used to study the role of B cells and antibodies. This study has implications for advancing immune research in teleosts and for developing strategies to improve salmon health and welfare in aquaculture.
传染病给挪威大西洋鲑鱼养殖带来了重大挑战。疫苗对疾病预防至关重要；然而，深入了解免疫系统对于提高疫苗效力至关重要。免疫球蛋白M（IgM）是硬骨鱼包括大西洋鲑鱼全身免疫反应中涉及的主要抗体。在本研究中，我们使用CRISPR/Cas9技术敲除了大西洋鲑鱼中的两个IgM基因。高通量测序显示两个位点的平均诱变效率为97%，移码突变占主导（78%）。基因表达分析表明，头肾和脾脏组织中膜结合IgM mRNA水平显著降低。流式细胞术显示外周血中IgM B细胞减少了78%，蛋白质印迹分析显示血清中IgM蛋白水平降低。值得注意的是，观察到IgT mRNA上调，提示可能存在补偿机制。这项工作首次应用CRISPR/Cas9在大西洋鲑鱼F0代中破坏免疫相关基因，为生成完全缺乏IgM B细胞的模型奠定了基础，该模型可用于研究B细胞和抗体的作用。本研究对推进硬骨鱼免疫研究以及制定改善水产养殖中鲑鱼健康和福利的策略具有重要意义。
