Serum granulocyte colony-stimulating factor levels are not increased in patients with autoimmune neutropenia of infancy.
OBJECTIVE
To assess the role of granulocyte colony-stimulating factor (G-CSF) in autoimmune neutropenia (AIN).


METHODS
Serum G-CSF levels were measured in 57 children with AIN. Two different G-CSF-dependent assays were used: a solid-phase "sandwich" enzyme-linked immunosorbent assay and a proliferation assay. Sera from healthy persons and from patients with severe congenital neutropenia were used for negative and positive controls.


RESULTS
The median G-CSF level in healthy persons (n = 13) was low, 45.6 pg/mL (range <39 to 141 pg/mL). The median G-CSF level in patients with AIN (n = 57) was very similar, 45.5 pg/mL (range <39 to 2500 pg/mL). Forty-five (79%) of 57 patients with AIN had levels within the range of the control group. Seven (12%) had marginally increased G-CSF levels (141 to 400 pg/mL), and only 5 (9%) had levels higher than 400 pg/mL. The G-CSF levels measured by enzyme-linked immunosorbent assay correlated well with levels measured by the proliferation assay, thus demonstrating that antibodies present in patient sera did not affect the biologic activity of G-CSF.


CONCLUSIONS
G-CSF production in AIN is not increased despite the low neutrophil count, similar to thrombopoietin in immune thrombocytopenic purpura.
Corbacioglu
S
S
Division of Hematology/Oncology, Department of Pediatrics, The New York Hospital and Cornell Medical College, New York, NY 10021, USA.
Bux
J
J
König
A
A
Gabrilove
J L
JL
Welte
K
K
Bussel
J B
JB
D001327:Autoimmune Diseases / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D016179:Granulocyte Colony-Stimulating Factor / Q000097:blood*; D006801:Humans; D007118:Immunoassay; D007223:Infant; D009503:Neutropenia / Q000097:blood*; D012680:Sensitivity and Specificity; D014407:Tumor Cells, Cultured
D016179:Granulocyte Colony-Stimulating Factor