Complement receptors CD21/35 link innate and protective immunity during Streptococcus pneumoniae infection by regulating IgG3 antibody responses

Academic Article


  • The CD21/35 receptor provides an important link between innate and adaptive immunity. Its importance during protective immune responses to encapsulated extracellular bacteria was assessed using a new line of mice completely deficient in CD21/35 expression (CD21/35-/-). CD21/35 expression was essential for the rapid trapping of C3dg-antigen complexes by B cells in vivo, especially in splenic marginal zones. Despite normal B cell development in CD21/35-/- mice, T cell-independent and -dependent antibody responses to low-dose antigens were significantly decreased, with a striking impairment in IgG3 responses. Accordingly, CD21/35-/- mice were more susceptible to acute lethal Streptococcus pneumoniae infection. Thus, CD21/35 expression is critical for early protective antibody responses to lethal pathogens that rapidly multiply and quickly overwhelm the immune system.
  • Authors

    Published In

  • Immunity  Journal
  • Digital Object Identifier (doi)

    Pubmed Id

  • 12631391
  • Author List

  • Haas KM; Hasegawa M; Steeber DA; Poe JC; Zabel MD; Bock CB; Karp DR; Briles DE; Weis JH; Tedder TF
  • Start Page

  • 713
  • End Page

  • 723
  • Volume

  • 17
  • Issue

  • 6