Complement and natural antibody are required in the long-term memory response to influenza virus

Vaccine. 2008 Dec 30;26 Suppl 8:I86-93. doi: 10.1016/j.vaccine.2008.11.057.


Complement, complement receptors and natural antibody (IgM) are important factors in the immune response against pathogens. Previous studies have indicated a role for C3, the complement receptors CD35/CD21 (CR1/CR2), and IgM in the immune response to influenza virus. Nevertheless, their contribution to the long-term memory response to this pathogen remains unknown. To elucidate this role, we characterized the secondary response on mice deficient of CR1/CR2 (Cr2-/-), C3 (C3-/-), secreted IgM (micros-/-) and the double knockout C3-/-micros-/-. Overall, our results suggest that C3, IgM and CR1/CR2 play crucial roles in the maintenance of long-term memory to influenza virus, possibly through the development of memory B cells and long-term antibody secretion.

MeSH terms

  • Animals
  • Antibodies, Viral / blood
  • Complement C3 / physiology*
  • Immunoglobulin G / blood
  • Immunoglobulin M / physiology*
  • Immunologic Memory*
  • Mice
  • Mice, Inbred C57BL
  • Orthomyxoviridae / immunology*
  • Receptors, Complement 3b / physiology*
  • Receptors, Complement 3d / physiology*


  • Antibodies, Viral
  • Complement C3
  • Immunoglobulin G
  • Immunoglobulin M
  • Receptors, Complement 3b
  • Receptors, Complement 3d