CYTOSOLIC PROTEINS FROM NEUTROPHILIC GRANULOCYTES - A COMPARISON BETWEEN PATIENTS WITH SEVERE CHRONIC NEUTROPENIA AND HEALTHY DONORS

A modified technique of two-dimensional gel electrophoresis (2-DE) was used to investigate differences in the pattern of cytosolic proteins of neutrophilic granulocytes from patients with severe congenital neut ropenia, cyclic neutropenia, and idiopathic neutropenia in comparison with healthy donors. At the time of study, all patients tested receive d treatment with a recombinant human granulocyte colony-stimulating fa ctor (r-metHuG-CSF; Filgrastim, Amgen). Using the Investigator 2-D Ele ctrophoresis System(TM) (Millipore) we were able to detect more than 1 000 protein spots in the cytosol of neutrophilic granulocytes from bot h patients and healthy controls. We investigated six patients with sev ere congenital neutropenia, five patients with cyclic neutropenia, fou r patients with idiopathic neutropenia, and 13 healthy donors. In the cytosol of neutrophilic granulocytes from patients we found an additio nal protein spot. This protein spot (molecular mass approximately 32.4 kDa, pI about 5.5) could be identified by internal sequencing after i n-gel digestion with endoproteinase Lys-C as tropomyosin. The importan ce of the overexpression of tropomyosin in neutrophilic granulocytes f rom patients with severe chronic neutropenia is not yet understood.