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ARS Home » Southeast Area » Auburn, Alabama » Aquatic Animal Health Research » Research » Publications at this Location » Publication #400974

Research Project: Integrated Research to Improve Aquatic Animal Health in Warmwater Aquaculture

Location: Aquatic Animal Health Research

Title: A recombinant 9E1 monoclonal antibody binds membrane and soluble channel catfish immunoglobulin M

item Lange, Miles
item CHURCHMAN, EMILY - Auburn University
item WISE, ALLISON - Auburn University
item BRUCE, TIMOTHY - Auburn University

Submitted to: Fish and Shellfish Immunology Reports
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/16/2023
Publication Date: 2/22/2023
Citation: Lange, M.D., Churchman, E.M., Wise, A.L., Bruce, T.J. 2023. A recombinant 9E1 monoclonal antibody binds membrane and soluble channel catfish immunoglobulin M. Fish and Shellfish Immunology Reports. 4:100086.

Interpretive Summary: The incidence of different bacterial diseases and their ongoing contribution to on-farm losses including the cost of therapeutants during the production cycle persists among the U.S. catfish industry accounting for as much $17 million in overall annual lost revenue. Vaccination remains a practical alternative that has proven to be effective in the control of many pathogens in the catfish industry. The successful evaluation for correlates of protection after vaccination requires performing different immunoassays while using specialized laboratory reagents. A recombinant 9E1 monoclonal antibody (r9E1 mAb) was developed as a new reagent to complement the existing 9E1 hybridoma cell line. The r9E1 mAb was successfully applied to ELISA, ELISPOT, and flow cytometry techniques for catfish immunology investigations. This tool will afford researchers a tool with higher-yielding protein production and increase protocol reproducibility.

Technical Abstract: The development and validation of the recombinant 9E1 monoclonal antibody against channel catfish IgM is described. The variable heavy and light chain domains of the 9E1 hybridoma were cloned into murine IgG1 and IgK expression vectors. These expression plasmids were co-transfected into 293F cells and mature IgG was purified from culture supernatants. It is demonstrated that the recombinant 9E1 monoclonal antibody binds to soluble IgM in ELISA and ELISPOT assays and to membrane-bound IgM by immunofluorescence with different B-cell types. The recombinant 9E1 monoclonal antibody will be a valuable tool in the continued examination of the channel catfish adaptive immune system.