Professional Protein Expression and Antibody Customization Services for Grass Carp C5a-CP Adjuvant Research

Customer Background
In the field of aquaculture, disease prevention in fish is a global challenge, with vaccines and adjuvants receiving significant attention. A recent study published in Fish and Shellfish Immunology (DOI: 10.1016/j.fsi.2025.110415) demonstrated the remarkable potential of grass carp complement C5a C-terminal peptide (C5a-CP) as a vaccine adjuvant. Conducted jointly by Huazhong Agricultural University and Pearl River Fisheries Research Institute, the study revealed the critical role of C5a-CP in enhancing the phagocytic activity of grass carp IgM⁺ B cells and improving vaccine efficacy, providing a vital theoretical foundation for the development of fish vaccine adjuvants.

Customer Needs
The study requires the expression of the grass carp IgM heavy chain constant region (IgM-CH) and the preparation of polyclonal antibodies (pAbs) against C5aR to validate the immune regulatory mechanism of C5a-CP.

Technical Challenges
1. Protein Expression and Purification: Due to their unique structure and sequence, fish proteins like grass carp IgM-CH often misfold or exhibit low expression levels in heterologous systems (e.g., E. coli), requiring optimized expression conditions and purification processes.
2. Antibody Specificity: Preparation of anti-C5aR antibodies requires designing antigens targeting specific epitopes (e.g., C5aR N-terminal peptide) to ensure specific binding to the target protein while avoiding non-specific signal interference.
3. Functional Validation: Recombinant proteins and antibodies must maintain biological activity in complex experiments (e.g., phagocytosis assays, Ca²⁺ mobilization tests), necessitating stringent quality control.

Technical Service Solutions
We offer comprehensive protein expression and antibody customization services to support grass carp C5a-CP research:

1. Recombinant IgM-CH Expression and Purification:

(1) Express GST-tagged IgM-CH (GenBank: DQ417927.1) in an E. coli system, using IPTG induction and gradient urea dialysis for refolding, ensuring protein purity >95% and activity verified by ELISA. 

(2) Employ affinity chromatography combined with BCA quantification to meet standard curve requirements (0.015625–0.25 μmol/L).

2. Anti-C5aR pAbs Customization and Validation:

(1) Design antigens targeting the C5aR N-terminal peptide (DYGPFDFSNESYSC) to produce rabbit-derived pAbs, validated for specificity via immunofluorescence and flow cytometry to ensure accurate labeling of C5aR⁺ cells.
(2) Delivery within 4–6 weeks to meet project timelines.

3. Functional Validation Support:
(1) Provide ELISA for IgM-CH activity testing and flow cytometry to confirm the specificity of anti-C5aR pAbs in IgM⁺ B cells.
(2) Support Ca²⁺ mobilization (Fluo4-AM) and phagocytosis assays (fluorescent beads) to ensure reliable validation of C5a-CP function.

Our protein expression and antibody customization technologies ensure a stable supply of IgM-CH protein and anti-C5aR antibodies, supporting critical validation in vaccine adjuvant development. Research results show that C5a-CP significantly enhances grass carp immune protection against Aeromonas hydrophila and GCRV-II, achieving a relative percent survival (RPS) of 96.03%, paving new paths for fish vaccine adjuvant development.

Contact us for customized protein expression and antibody services! Visit www.atagenix.com. Our professional team provides end-to-end support from antigen design to functional validation, helping your research achieve global recognition!