Complement receptor type 1 (CD35) mediates inhibitory signals in human B lymphocytes

Research output: Contribution to journalArticle

59 Citations (Scopus)


The complement system-particularly component C3-has been demonstrated to be a key link between innate and adaptive immunity. The trimolecular complex of complement receptor type 2 (CR2), CD19, and CD81 is known to promote B cell activation when coligated with the B cell Ag receptor. In the present study, we aimed to elucidate the role of human complement receptor type 1 (CR1), the other C3-receptor on B cells. As ligand, aggregated C3 and aggregated C3(H2O), i.e., multimeric "C3b-like C3", are used, which bind to CR1, but not to CR2. In experiments studying the functional consequences of CR1-clustering, the multimeric ligand is shown to inhibit the proliferation of tonsil B cells activated with a suboptimal dose of anti-IgM F(ab′)2. Importantly, this inhibitory activity also occurs in the presence of the costimulatory cytokines IL-2 and IL-15. The anti-IgM-induced transient increase in the concentration of intracellular free Ca2+ and phosphorylation of several cytoplasmic proteins are strongly reduced in the presence of the CR1 ligand. Data presented indicate that CR1 has a negative regulatory role in the B cell Ag receptor mediated activation of human B lymphocytes.

Original languageEnglish
Pages (from-to)2782-2788
Number of pages7
JournalJournal of Immunology
Issue number6
Publication statusPublished - Mar 15 2002

ASJC Scopus subject areas

  • Immunology and Allergy
  • Immunology

Fingerprint Dive into the research topics of 'Complement receptor type 1 (CD35) mediates inhibitory signals in human B lymphocytes'. Together they form a unique fingerprint.

  • Cite this