Development and application of monoclonal antibody against IgM of hybrid snakehead (Channa maculata♀ × Channa argus♂)

Hybrid snakehead (C. maculate ♀ ×C. argus♂) culture has become an important aquaculture in China. However, severe disease caused by bacterial and viral infections resulted in enormous economic losses in the recent years. The effective disease control strategies have not been developed due to limited understanding of the immunology of this species so far. In this study, monoclonal antibodies (mAb) against serum immunoglobulin M (IgM) purified from hybrid snakehead was developed by stimulating mice, of which spleen cells were fused with myeloma cells to generate stable and effective antibody-producing hybridoma cells. The mAb clone number named as 1C3-1–12 and the mAb was further screened successfully using an indirect enzyme-linked immunosorbent assay (iELISA). Western blot analysis showed that the mAb 1C3-1–12 can specifically react with the heavy chain of IgM. There were no cross-reactions with sera from three other teleosts. Meanwhile, the mAb 1C3-1–12 can effectively detect serum IgM levels of hybrid snakehead and its evolutionally closely related species. Moreover, the mAb 1C3-1–12 was found to exclusively recognize the IgM+ B cells of hybrid snakehead by indirect immunofluorescence assay (IFA). Collectively, we developed a useful and specific monoclonal antibody against serum IgM from hybrid snakehead and will be an important immunological tool for better understanding the function of the immune system of hybrid snakehead. It may lie as a foundation for the establishment of diagnosis of disease and the development of effective vaccine.