Purification of a non-tagged recombinant BCG heat shock protein 65-Her2 peptide fusion protein from Escherichia coli

Protein Expr Purif. 2007 Jun;53(2):390-5. doi: 10.1016/j.pep.2006.12.015. Epub 2006 Dec 24.

Abstract

Bacille Calmette-Guerin (BCG)-derived heat shock protein 65 (HSP65) has been demonstrated capable of assisting a fused peptide to generate the peptide-specific cellular immunity. Various HSP65 fusion proteins have been developed as therapeutic cancer vaccines. Purifying a recombinant HSP65 fusion protein with no purification tags for human use is routinely a challenge. Here, we report a scheme for purifying a non-tagged recombinant HSP65-Her2 peptide fusion protein (HSP65-Her2) from Escherichia coli. The HSP65-Her2 is being developed as an immunotherapeutic for the treatment of Her2-positive tumors. After fermentation in a 10-L fermentor, the HSP65-Her2 expressing E. coli were harvested and lysed by sonication. The recombinant HSP65-Her2 was then purified with four successive steps including Butyl-Sepharose FF, DEAE-Sepharose FF, 1% Triton X-114 phase separation and Sephadex G-25. Results showed that HSP65-Her2 was purified up to 97% purity and was able to generate Her2-specific cytotoxic T lymphocytes (CTLs), suggesting that the scheme is efficient for purifying the non-tagged HSP65-Her2 fusion protein with biological activity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • B7-2 Antigen / metabolism
  • Bacterial Proteins / genetics*
  • Bacterial Proteins / immunology
  • Bacterial Proteins / isolation & purification*
  • Base Sequence
  • Chaperonin 60
  • Chaperonins / genetics*
  • Chaperonins / immunology
  • Chaperonins / isolation & purification*
  • DNA Primers / genetics
  • Escherichia coli / genetics*
  • Gene Expression
  • Genes, Bacterial
  • Genes, erbB-2
  • Humans
  • In Vitro Techniques
  • Mycobacterium bovis / genetics*
  • Receptor, ErbB-2 / genetics*
  • Receptor, ErbB-2 / immunology
  • Receptor, ErbB-2 / isolation & purification*
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / immunology
  • Recombinant Fusion Proteins / isolation & purification
  • T-Lymphocytes, Cytotoxic / immunology

Substances

  • B7-2 Antigen
  • Bacterial Proteins
  • CD86 protein, human
  • Chaperonin 60
  • DNA Primers
  • Recombinant Fusion Proteins
  • heat-shock protein 65, Mycobacterium
  • Receptor, ErbB-2
  • Chaperonins