Soluble ICAM-4Fc binds specifically to immobilized purified CD11c/CD18 in a solid-phase assay. (A) Dose-dependent binding of recombinant ICAM-4Fc to coated integrins. ICAM-4Fc + CD11a/CD18 (▪), ICAM-4Fc + CD11b/CD18 (○), ICAM-4Fc + CD11c/CD18 (▴). Background binding of control protein (human IgG1) was subtracted. (B) The effect of monoclonal antibodies on binding of soluble ICAM-4Fc to 0.4 μmg coated CD11c/CD18 in a solid-phase assay is shown. The ICAM-4Fc binding to CD11c/CD18 was examined in the presence of mAbs (50 μmg/mL) against the ICAM-4 (1A1), CD18 (7E4), and CD11c (3.9, BU15). Data shown are from 1 representative experiment of 3. Standard deviations and statistical significances are shown; ***P < .005, **P< .05. The significances were determined by unpaired Student t test.
