Expression of anticardiolipin cofactor, human β2-glycoprotein I, by a recombinant baculovirus/insect cell system

M. Igarashi, E. Matsuura, Y. Igarashi, H. Nagae, Y. Matsuura, K. Ichikawa, T. Yasuda, D. R. Voelker, T. Koike

Research output: Contribution to journalArticlepeer-review

14 Citations (Scopus)


A full-length cDNA coding a human β2-glycoprotein I (β2-GPI) was introduced into the baculovirus genome to construct a recombinant baculovirus. Spodoptera frugiperda (Sf9) cells were infected with the recombinant baculovirus. A protein (mol. wt 43000) reactive with anti-β2-GPI antisera was produced in the insect cells and secreted into the culture medium. The recombinant β2-GPI was purified from the culture supernatant by sequential cardiolipin (CL)-affinity column chromatography and gel filtration. The N-terminal amino acid sequence of the protein was identical to that of the native β2-GPI purified from human sera, and a putative signal peptide was cleaved from the secreted form of the recombinant protein. The purified recombinant protein had a cofactor activity which enhances CL binding of anticardiolipin antibodies (aCL) in systemic lupus erythematosus (SLE) patients, as well as the native β2-GPI. Thus, the β2-GPI expressed in insect cells is an immunologically active cofactor.

Original languageEnglish
Pages (from-to)19-25
Number of pages7
JournalClinical and Experimental Immunology
Issue number1
Publication statusPublished - 1993
Externally publishedYes


  • anticardiolipin antibodies
  • baculovirus expression
  • glycosylation
  • recombinant DNA

ASJC Scopus subject areas

  • Immunology and Allergy
  • Immunology


Dive into the research topics of 'Expression of anticardiolipin cofactor, human β<sub>2</sub>-glycoprotein I, by a recombinant baculovirus/insect cell system'. Together they form a unique fingerprint.

Cite this