Figure 3. Expression of integrins on human uveal (92–1, Mel202) and cutaneous melanoma (FM55P, IGR-39) cells. Melanoma cells were examined by flow cytometry for the expression of α₃β₁, α₄β₁, α₅β₁, and α_vβ₃ integrins, and data were compared to cells incubated with normal mouse IgG. Fluorescein isothiocyanate (FITC)-conjugated rabbit anti-mouse IgG (Fab’)₂ fragments were used for detection. Fluorescence signals of 10,000 cells were counted for each integrin subunit tested. Histograms of cells versus log fluorescence were generated. A: Panels show FACS profile for integrin-positive cell lines. Colored areas indicate the fluorescence profile of cells after indirect fluorescence staining with anti-integrin monoclonal antibodies. Open histograms represent background fluorescence. Relative fluorescence is shown as a logarithmic scale of 4 log cycles on the x-axis, and cell number as a linear scale on the y-axis. Data from one of three similar experiments are presented. The negative control for each line is different in some experiments because the experiments were not run on the same occasion. B: Diagram shows percentage of melanoma cells expressing α₃β₁, α₄β₁, α₅β_1, and α_vβ₃ integrins. C: Diagram shows quantitation of data from flow cytometric analyses. Values are means ± standard deviation of three separate experiments. Asterisk (*) indicates p<0.05.