Figure 3.

Peripheral blood cell adhesion to Fk. Peripheral blood was obtained from CX₃CR1 wild-type and null mice, and the leukocytes were isolated as a buffy coat. Cells were labeled with the fluorescent dye 2′,7′-bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein, acetoxymethyl ester, and tested for adhesion to Fk in cell culture chambers. Excess cells were washed off after a 30-minute incubation, and adhesion was measured as a function of fluorescence. Results are reported as arbitrary fluorescent units. Excess soluble Fk (100 nM) was added to compete with adhesion to the tethered Fk. This assay is representative of three performed. The adhesion of wild-type cells was significantly reduced by the addition of soluble Fk (P < 0.001).