Transwell Migration Assays with neutrophils NB4 cells will be used in this study. NB4 cells are a cultured human cell line for acute promyelolytic leukemia. They will be differentiated into neutrophils and then incubated in human control serum or patients samples prior to transwell migration assay. Migration without the neutrophil chemotactic factor N-formylmethionyl-leucyl-phenylalanine (fMLP) or toward fMLP will be allowed for 2 hours. The migrated cells in the bottom well will be counted vial flow cytometry. All samples will be run in triplicates.