Fig. 5. Effect of endocytosis inhibitors on anti-ICAM-1 and anti-PECAM-1 uptake. Uptake of anti-ICAM-1 and anti-PECAM-1 immunobeads was quantified as mean±s.d. by fluorescence microscopy using control cells, potassium-depleted cells or cells pretreated for 30 minutes at 37°C before incubation with immunobeads with either 50 µM MDC, 50 µM genistein, 1 µg/ml filipin, 3 mM amiloride or 25 µM monensin. Cells incubated with anti-ICAM-1 or anti-PECAM-1 immunobeads at 4°C are controls for no internalization. *P<0.05.