NATURALLY-OCCURRING AND THERAPY-INDUCED ANTIBODIES TO HUMAN GRANULOCYTE-COLONY-STIMULATING FACTOR (G-CSF) IN HUMAN SERUM

Sera were obtained from two groups of patients. Group A included 7 pat ients with low-grade non-Hodgkin's lymphoma treated with three or more cycles of standard-dose chemotherapy and recombinant human granulocyt e-colony stimulating factor (rhG-CSF). The cytokine was administered t o half the patients after the first chemotherapy cycle and to the othe r half after the second according to a randomized design and then to a ll patients from the third chemotherapy cycle on, until documented hem opoietic reconstitution. Group B included 3 patients with high-grade n on-Hodgkin's lymphoma, 1 patient with resistant Hodgkin's disease, and 1 patient with multiple myeloma who received high-dose chemotherapy a nd rhG-CSF. Anti-G-CSF antibodies were detected in the sera of 4 patie nts. Both immunoglobulin IgM and IgG antibodies were detected at low l evels in pretreatment sera from one group A patient. IgG antibody tite rs increased markedly during the first and second periods of G-CSF adm inistration. IgG class antibodies developed in 3 group B patients duri ng the first course of rhG-CSF administration. Circulating anti-G-CSF antibodies did not seem to affect hematological recovery. Low levels o f anti-G-CSF antibodies were also detected in sera (15/135) from diffe rent healthy adults and in sera (5/40) from umbilical cord blood. Satu rable antibody binding and competition enzyme-linked immunosorbent ass ay (ELISA) and immunoblotting confirmed antibody specificity. (C) 1997 Wiley-Liss, Inc.