title: [The inhibitory effect of recombinant human C3 fragment on murine endotoxic shock].
abstract: OBJECTIVE
  To study the potentially practical use of C3 inactive fragment in anti-inflammation.
  
  
  METHODS
  A vector expressing RGD polypeptide derived from the alpha chain segment of human C3 was constructed by using PCR and genetic engineering methods and a recombinant protein (namely C 33) was expressed with high efficiency in E. coli.
  
  
  RESULTS
  The analysis of SDS-PAGE showed the molecular weight of C 33 was about 15 KD. Its purity was above 95% after purification. The amino acid composition was inconsistent with the theoretical values. U937 cells stimulated by low dosage PMA adhered with coated C 33, and the adhesion was blocked by anti-CD 11b monoclonal antibody. After injection of purified C 33 into mice which were consequently challenged by dead E. coli, the mortality of the endotoxic shock was significantly reduced.
  
  
  CONCLUSIONS
  C 33 can specifically bind to CD 11b/CD 18. C 33 as a ligand for CD 11b/CD 18 might be potentially used as an anti-inflammatory agent.
authors.affiliation: Department of Immunology, Beijing Medical University.
authors.forename: H
authors.initials: H
authors.lastname: Liang
authors.forename: Q
authors.initials: Q
authors.lastname: Song
authors.forename: Y
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D003176:Complement C3 / Q000494:pharmacology*; D004926:Escherichia coli / Q000235:genetics; D005260:Female; D005818:Genetic Engineering; D006801:Humans; D007128:Immunoglobulin Fragments / Q000494:pharmacology; D051379:Mice; D008807:Mice, Inbred BALB C; D011994:Recombinant Proteins / Q000494:pharmacology*; D012772:Shock, Septic / Q000517:prevention & control*
chemical_list: D000893:Anti-Inflammatory Agents; D003176:Complement C3; D007128:Immunoglobulin Fragments; D011994:Recombinant Proteins