The CD11c antigen couples concanavalin A binding to generation of superoxide anion in human phagocytes

P. M. Lacal, J. Balsinde, C. Cabanas, C. Bernabeu, F. Sanchez-Madrid, F. Mollinedo

Research output: Contribution to journalArticlepeer-review


We have found that an anti-CD11c monoclonal antibody (MAb) inhibits the respiratory burst induced in phorbol 12-myristate 13-acetate (PMA)-differentiated U937 cells as well as in human peripheral blood monocytes and neutrophils upon cell stimulation with concanavalin A. The MAb had no effect, however, when the added stimulus was fMet-Leu-Phe or PMA. Flow cytometry analyses indicated that concanavalin A was able to interact with CD11c. The anti-CD11c MAb inhibited significantly concanavalin A binding to differentiated U937 cells, and concanavalin A blocked binding of anti-CD11c MAb to the cells. Binding of labelled concanavalin A to membrane proteins which were separated by PAGE and transferred to nitrocellulose paper indicated that proteins with apparent molecular masses similar to those of CD11c (150 kDa) and CD18 (95 kDa) molecules were the main concanavalin A-binding proteins in differentiated U937 cells as well as in mature neutrophils. Similar experiments carried out in the presence of the anti-CD11c MAb showed a specific and significant inhibition of concanavalin A binding to the CD11c molecule. These results indicate that concanavalin A binds to the CD11c molecule and this binding is responsible for the concanavalin A-induced respiratory burst in PMA-differentiated U937 cells as well as in human mature monocytes and neutrophils.

Original languageEnglish
Pages (from-to)707-712
Number of pages6
JournalBiochemical Journal
Issue number3
Publication statusPublished - 1990

ASJC Scopus subject areas

  • Biochemistry


Dive into the research topics of 'The CD11c antigen couples concanavalin A binding to generation of superoxide anion in human phagocytes'. Together they form a unique fingerprint.

Cite this