Increase in red cell filterability after incubation with oxpentifylline.

Red cells from patients with various diseases known to decrease red cell filterability were washed and incubated in oxpentifylline suspended in buffered saline. An improvement of red cell filterability could be observed which was independent of the aetiology of red cell rigidity. The improvement was related to the initial degree of abnormality. No change was observed in normal cells or cells more than 4 hours old.