Competition between lymphocyte function-associated antigen 1 (CD11a/CD18) and Mac-1 (CD11b/CD18) for binding to intercellular adhesion molecule-1 (CD54).
Both human integrin receptors Mac-1 (CD11b/CD18,CR3)and lymphocyte function-associated antigen (LFA)-1 (CD11a/CD18) have been demonstrated to bind human intercellular adhesion molecule-1 (ICAM-1) (CD54). Here we show that LFA-1 and Mac-1 can bind to ICAM-1 in the mouse as well. Interestingly, we observed that binding of murine LFA-1 dominates over Mac-1 for binding to ICAM-1. Using three different murine macrophage cell lines that express distinct levels of LFA-1 and Mac-1 on their cell surface, we could only detect Mac-1-dependent adhesion to ICAM-1 when little or no LFA-1 is expressed on the cell surface. When LFA-1 and Mac-1 are expressed at similar levels, the LFA-1/ICAM-1 interaction dominates over Mac-1/ICAM-1 interaction, indicating that there is a competition of LFA-1 and Mac-1 for ICAM-1 binding.
Lub
M
M
Division of Tumor Immunology, University Hospital Nijmegen St. Radboud, Nijmegen, The Netherlands.
van Kooyk
Y
Y
Figdor
C G
CG
D000818:Animals; D001667:Binding, Competitive; D002448:Cell Adhesion; D002460:Cell Line; D018799:Intercellular Adhesion Molecule-1 / Q000302:isolation & purification / Q000378:metabolism*; D016169:Lymphocyte Function-Associated Antigen-1 / Q000378:metabolism*; D016177:Macrophage-1 Antigen / Q000302:isolation & purification / Q000378:metabolism*; D008264:Macrophages / Q000378:metabolism; D051379:Mice
D016169:Lymphocyte Function-Associated Antigen-1; D016177:Macrophage-1 Antigen; D018799:Intercellular Adhesion Molecule-1