FIG. 6.
Cell aggregation activity of JAM4. (A) Cell aggregation assays were performed using L cells or stable transformants of L cells expressing JAM4 (L-JAM4) or JAM4ΔC (L-JAM4ΔC). The extent of cell aggregation is represented by the ratio of the total particle number at the indicated time point (Nt) to the initial particle number (N0). The Nt/N0 values are representative of the means ± standard errors of three independent experiments. (B) Expression of JAM4 and JAM4ΔC. Cell surface proteins were biotinylated, precipitated by avidin-agarose beads, and then immunoblotted with the anti-JAM4 antibody. Lane 1, wild-type L cells; lane 2, L-JAM4 cells; lane 3, L-JAM4ΔC cells. (C) Cell aggregation of L-JAM4 cells. Results for wild-type L cells (L-w.t.), L-JAM4 cells (L-JAM4), and L-JAM4ΔC cells (L-JAM4ΔC) at 60 min in a cell aggregation assay are shown. Bar, 200 μm.