Serum Concentrations of Granulocyte Colony-Stimulating Factor (G-CSF) Determined by A Highly-Sensitive Chemiluminescent Immunoassay during the Clinical Course of Subacute Thyroiditis

Abstract

Granulocyte colony-stimulating factor (G-CSF) concentrations in serum were determined for the first time by a newly developed and highly sensitive chemiluminescent immunoassay (the limitation of detection, 0.5pg/ml) in ten patients with subacute thyroiditis, during treatment with glucocorticoid or indomethacin. Before therapy, circulating neurophil counts significantly increased to 5.15±2.07× 10³/μl compared with the convalescent phase (2.94±1.07×10³/μl), and the data were correlated with individual serum G-CSF levels (r=0.854, P<0.01). Serum concentrations of interleukin-3 (IL-3) and granulocyte-macrophage colony-stimulating factor (GM-CSF) were less than the detectable threshold of ELISA. During two weeks of glucocorticoid therapy, although the circulating neutrophil counts increased from 5.15±2.46×10³/μl to 7.73±1.64×10³/μl (P<0.01), serum G-CSF levels were depressed from 25.1±15.3pg/ml to 13.8±13.9pg/ml (P<0.01). These data indicate that G-CSF is one of the mediators of the increase of neutrophils in subacute thyroiditis, while it does no contribute to steroid-induced neutrophilia.