Complement-mediated early clearance of Haemophilus influenzae type b from blood is independent of serum lytic activity

J Infect Dis. 1988 Jan;157(1):85-90. doi: 10.1093/infdis/157.1.85.


The role of complement-mediated serum lytic activity in the clearance of encapsulated Haemophilus influenzae type b was studied by comparing clearance of bacteria from blood in normal mice with that in congeneic C5-deficient animals and mice depleted of complement by using cobra-venom factor. The clearance of organisms from blood by C5-deficient and C5-sufficient normal animals was similar. C3 depletion and the inability to fix C3 to the surface of bacteria were, however, associated with impaired clearance of organisms during the first 24 h after intravenous bacterial challenge. These studies suggest that complement-mediated opsonization rather than bacteriolysis is important in determining early clearance of H. influenzae type b from the bloodstream.

MeSH terms

  • Animals
  • Antibodies, Bacterial / analysis
  • Blood Bactericidal Activity*
  • Complement C3 / immunology
  • Complement C5 / deficiency
  • Complement C5 / immunology
  • Complement System Proteins / immunology*
  • Elapid Venoms / pharmacology
  • Enzyme-Linked Immunosorbent Assay
  • Haemophilus influenzae*
  • Male
  • Mice
  • Mice, Inbred Strains
  • Opsonin Proteins / immunology


  • Antibodies, Bacterial
  • Complement C3
  • Complement C5
  • Elapid Venoms
  • Opsonin Proteins
  • cobra venom factor
  • Complement System Proteins