Neutrophil activation in sickle cell disease

Vascular occlusion is the main cause of the morbidity and mortality observe d in patients with sickle cell disease (SCD), Increasing evidence indicates that (activated) neutrophils could play an important role in the initiatio n and propagation of vaso;occlusive processes in SCD, In this study, the ac tivation state of neutrophils in sickle cell patients was analyzed by deter mining the level of expression of neutrophil antigens such as CD62L, CD11b, CD66b, CD63, and Fc gamma receptors, We also analyzed plasma levels of lac toferrin, elastase, soluble (s)CD16 (sFc gamma RIII), and serum levels of s oluble (s)CD62L (sL-selectin) as neutrophil activation markers in these pat ients. Significant differences were observed in the activation state of neu trophils in non-symptomatic sickle cell patients compared to healthy HbAA c ontrols as exemplified by significant decrease in L-selectin expression, en hanced expression of CD64, and increased levels of soluble markers like sL- selectin, elastase, and sCD16, During vaso-occlusive crisis the differences were even more pronounced. These results show neutrophils to be activated in sickle cell patients, suggesting a role of importance in the pathophysio logy of sickle cell disease.