IMPROVED IMMUNODIAGNOSTIC ASSAY USING REDUCING AGENTS

摘要

The present invention relates to a solid phase immunoassay comprising on sai d solid phase an antigen in the presence of a reducing agent. The present invention also relates to a method for purifying a cysteine containing recombinantly expressed protein comprising at least 2, preferably 3 or 4 and even more preferably all of the following steps: (a) sulphonation of a lysate from recombinant host cells or lysis of recombinant host cells in the presence of guanidinium chloride followed by a subsequent sulphonation o f the cell lysate, (b) treatment with a zwitterionic detergent, preferably after remova l of the cell debris, (c) purification of the sulphonated version of the recombinant prote in or purification of the sulphonated version of the recombinant protein with subsequent removal of the zwitterionic detergent, with said purification being preferab ly chromatography, more preferably a Ni-IMAC chromatography with said recombina nt protein being a His-tagged recombinant protein, (d) desulphonation of the sulphonated version of the recombinant protein, preferably with a molar excess of DTT, ( e) storage in the presence of a molar excess of DTT. The present invention also relates to novel HCV NS3 sequences as depicted in Figures 1-8.