“…This was loaded onto a 17.2% Nycodenz solution and covered the layer with 1 ml of HBSS. Following centrifugation for 15 min at 3,000 g, the cells at the top of the Nycodenz were collected, and washed by centrifugation (Hendriks et al, 1985;Vyas et al, 1995;Geerts et al, 1998).…”