SERUM LEVELS OF MAJOR BASIC-PROTEIN IN PATIENTS WITH OR WITHOUT EOSINOPHILIA - MEASUREMENT BY ENZYME-LINKED-IMMUNOSORBENT-ASSAY

A bone marrow proteoglycan (BMPG) has been purified which consists of the same amino acid sequence as that of pro-MBP, and produced two anti -BMPG mAbs. Serum levels of major basic protein (MBP), a cationic prot ein rich in the eosinophil granule, were measured in patients with eos inophilia or allergic diseases by an enzyme-linked immunosorbent assay (ELISA) using these mAbs. The serum levels of MBP in patients with eo sinophilia (n = 64) and in those with allergic diseases without eosino philia (n = 32) were elevated significantly (P<0.001 and P=0.038, resp ectively). There was a weak positive correlation between the serum lev els of MBP and the eosinophil counts in the patients with eosinophilia (r=0.38). Among these patients, extremely high serum levels of MBP we re found in those with hypereosinophilic syndrome (HES) and Kimura's d isease. Serum levels of MBP decreased more slowly than the eosinophil counts in patients with eosinophilia when treated by glucocorticoids. We conclude that measurement of serum levels of MBP is useful in evalu ating the total-body proliferation and infiltration of eosinophils mor e accurately than following-up the eosinophil counts alone.