Molecular interactions of complement receptors on B lymphocytes: A CR1/CR2 complex distinct from the CR2/CD19 complex

David A. Tuveson, Joseph M. Ahearn, Alan K. Matsumoto, Douglas T. Fearon

Research output: Contribution to journalArticle


The complement system augments the humoral immune response to low concentrations of antigen. This effect may be partly mediated by complement receptors on the surface of B lymphocytes that bind immunogenic complexes bearing fragments of C3 and C4. We have shown by immunoprecipitation analysis that the two complement receptors expressed by B lymphocytes, complement receptor 1 (CR1) and CR2, form a detergent-sensitive complex on the surface of tonsillar B lymphocytes and on K562 erythroleukemia cells that were co-transfected with cDNAs encoding CR1 and CR2. The CR1/CR2 complex is distinct from the CR2/CD19 complex and may assist B cell activation by efficiently capturing C3b-containing immunogens and maintaining such immunogens on the B cell after CR1 and factor I-mediated cleavage to iC3b and C3dg. The complement activating immunogen may then trigger signal transduction by the CR1/CR2 complex, the CR2/CD19 complex, or membrane immunoglobulin.

Original languageEnglish (US)
Pages (from-to)1083-1089
Number of pages7
JournalJournal of Experimental Medicine
Issue number5
StatePublished - May 1 1991


ASJC Scopus subject areas

  • Immunology and Allergy
  • Immunology

Cite this