Sickle cell anemia (SCA) is a genetic disorder characterized by chronic hemolysis and the presence of erythrocytes with low deformability, which may trigger vaso-occlusive crises. We tested the in-vitro effects of aqueous extract of chives (Allium schoenoprasum L.) on erythrocyte deformability of SCA patients. Blood samples from 6 apparently healthy volunteers and 5 SCA patients were collected into heparin coated tubes. Both apparently healthy and SCA patient blood samples were incubated with 80 mu g/mL chives plant aqueous extract at 37 degrees C for 60 min and erythrocyte deformability was measured by ektacytometry (3 Pa and 30 Pa; 37 degrees C). Results of incubation of apparently healthy blood samples with plant extract showed that incubation did not alter erythrocyte deformability significantly. However, for SCA blood samples, erythrocyte deformability decreased significantly with plant extract exposure at 3 Pa (p < 0.043) and 30 Pa (p < 0.043). In conclusion, although ex-vivo incubation with plant extract does not fully model gastrointestinal processing of onions, the decrease in SCA erythrocyte deformability following incubation with aqueous chives should stimulate further studies to test the in-vivo effects of this diet in sickle cell mice.