THE USE OF GENE FUSIONS TO PROTEIN-A AND PROTEIN-G IN IMMUNOLOGY AND BIOTECHNOLOGY

SUMM. This review describes the use of fusion proteins containing the immunoglobulin-binding domains of staphylococcal protein A (SpA) or th e serum albumin-binding regions of streptococcal protein G (SpG), resp ectively, for various applications in immunology and bio technology. T he review will not cover the use of SpA and SpG for the purpose of imm unoglobulin purification, but instead focus on other applications. Hun dreds of SpA/SpG fusion proteins have been described in publications i n the context of recombinant protein production, in a wide variety of host cells, with subsequent affinity purification of the gene product. However, this still constitutes just one area of their use. We will t hus cover also other aspects of using SpA and SpG, including strategie s to: (i) improve in vitro renaturation schemes for expressed gene pro ducts, (ii) enable affinity-assisted folding in vivo of target protein s, (iii) improve the stability to proteolysis of produced recombinant proteins, (iv) prolong the in vivo half-life of therapeutic proteins, (v) facilitate subunit vaccine development and functional cDNA analysi s, (vi) select novel receptor variants with new specificities by the u se of phage display technology.