Fig. 7
ICAM-1-independent adherence of T84 cells to purified CD11b/CD18.
Suspensions of BCECF-AM-labeled T84 cells (∼8 × 106/ml) were preincubated with saturating concentrations of the antibodies shown followed by adhesion to purified CD11b/CD18 in 96-well tissue culture plates as described in Materials and Methods. (A) Percentage of applied cells adherent to CD11b/CD18 after various antibody treatments is shown. Adhesion of control unstimulated T84 cells was compared with T84 monolayers stimulated with IFNγ. As an antibody control, adhesion in the presence of a noninhibitory anti-CD11b antibody, OKM1, was used. As a functionally inhibitory antibody to CD11b, mAb 44a was used by pretreating the CD11b/CD18 coated wells for 30 min at 10 µg/ml. (B) Adhesion of unstimulated T84 cells to purified CD11b/CD18 is compared with adhesion to CD11a/CD18 and bovine serum albumin (BSA). (C) The effect of saturating concentrations of functionally inhibitory anti-CD11b antibody (44a) on unstimulated T84 cell adhesion to CD11b/CD18, CD11a/CD18, and BSA is shown. Adherent T84 cells (nonlabeled) within a defined area were quantitated by microscopy as described previously (14). Values representative of one of two experiments showing the mean ± SD of quadruplicate determinations.