Aging Reduces the Functionality of Anti-Pneumococcal Antibodies and the Killing of Streptococcus Pneumoniae by Neutrophil Phagocytosis

Vaccine. 2011 Feb 24;29(10):1929-34. doi: 10.1016/j.vaccine.2010.12.121. Epub 2011 Jan 12.


We evaluated the effect of aging on the functional activity of naturally acquired anti-pneumococcal antibodies, the function of neutrophils in phagocytic killing of opsonized pneumococci, and the complement activity. Opsonic activities of antibodies to all tested pneumococcal serotypes were significantly lower and phagocytic killing of pneumococci by neutrophils was significantly impaired among the elderly, whereas the complement activity was slightly higher in the elderly than in the young adults. The reduced functional activity of serotype-specific antibodies and the compromised function of neutrophils in the opsonophagocytosis of pneumococci are likely to contribute to the increased susceptibility of the elderly to pneumococcal diseases.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Age Factors
  • Aged
  • Aged, 80 and over
  • Aging / immunology
  • Antibodies, Bacterial / blood*
  • Antibodies, Bacterial / immunology
  • Blood Bactericidal Activity*
  • Complement System Proteins / immunology
  • Female
  • Humans
  • Male
  • Middle Aged
  • Neutrophils / immunology*
  • Opsonin Proteins / blood
  • Opsonin Proteins / immunology
  • Phagocytosis*
  • Streptococcus pneumoniae / immunology*
  • Young Adult


  • Antibodies, Bacterial
  • Opsonin Proteins
  • Complement System Proteins