FIG. 4.

Effect of TAK-220 on RANTES-induced Ca²⁺ mobilization in (A) CCR5- and (B) CCR1-expressing cells. CCR5- or CCR1-expressing HeLa cells were suspended in ECB buffer, loaded with 10 μM Fura-PE3AM for 60 min, washed twice, and resuspended in the same buffer. At 90 s after exposure to various concentrations of TAK-220, 20 nM RANTES was added, and the relative increase in cytoplasmic Ca²⁺ levels was monitored with a fluorescence spectrometer.