SYNTHESIS OF RECOMBINANT POLYPEPTIDE INCLUDING CH2-CH3 DOMAINS OF THE HUMAN IgG1 Fc-FRAGMENT AND ITS USE FOR MOUSE POLYCLONAL ANTIBODY PRODUCTION

The recombinant polypeptide rFс IgG containing the amino acid sequence of the CH2 and CH3 domains of the Fc-fragment of the human IgG γ-chain was produced in Escherichia coli. The polypeptide rFс IgG is an antigen with many linear epitopes for human IgG. Wild-type mice were immunized with rFс IgG to obtain immune ascitic fluids containing polyclonal antibodies against human IgG. It was shown that rFс IgG was highly immunogenic for mice and could be used to produce polyclonal antibodies against human IgG. It was revealed that mouse polyclonal antibodies slightly cross-reacted with human IgM, in addition a high variability of titers of antihuman Ig derived from different mice was found. To solve these problems, it was offered to assess the quality of material obtained after every immunization and to select suitable antibody samples with appropriate avidity, specificity and titer. 

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