PRODUCTION, PURIFICATION AND ANTIGENIC SPECIFICITY OF RECOMBINANT POLYPEPTIDE INCLUDING CH2-CH3 DOMAINS OF Fc-FRAGMENT OF HUMAN IMMUNOGLOBULIN G
Recombinant polypeptide containing the amino acid sequence of the CH2-CH3 domains of human immunoglobulin G was produced in Escherichia coli. It was shown that the expressed protein was not equally distributed between two fractions of bacterial lysate: soluble (~ 30%) and insoluble (~ 70%). Methods of protein purification by means of metal-chelate affinity chromatography (soluble fraction) and isolation of “inclusion bodies” have been worked out. The antigenic specificity of the resulting recombinant polypeptide was confirmed in the western blotting analysis. Preparative quantities of protein were produced to be used as an immunogen to obtain immune ascitic fluids containing monospecific polyclonal antibodies against human IgG.