Given that PSGL-1 interaction with P-selectin induces Syk activation [13] and L-Selectin contributes to full activation of neutrophils, when interacting with P-selectin [33], we first studied the expression level of L-Selectin in the cell membrane and the level of pSyk in basal experimental conditions of neutrophils from HD and SLE patients. This evidence concerns the gene SELL and systemic lupus erythematosus.