Evaluation of recombinant canine granulocyte colony-stimulating factor as an inducer of granulopoiesis. A pilot study.
Five healthy young adult dogs were given recombinant canine granulocyte colony-stimulating factor (rcG-CSF) at a dosage of 5 micrograms/kg/day subcutaneously for 4 weeks to evaluate the effect on complete blood cell counts. The mean neutrophil counts +/- standard deviation (SD) increased significantly (P less than 0.01) from 6,537/microliters +/- 1,726 (range, 4,950-9,512/microliters) to 26,330/microliters +/- 7,066 (range, 15,368-35,785/microliters) within 24 hours after the first injection of rcG-CSF. Mean monocyte counts +/- SD were significantly increased (P less than 0.05) from baseline values of 751/microliters +/- 168 (range, 444-891/microliters) to 2,514/microliters +/- 878 (range, 1,740-3,752/microliters) on day 5 of rcG-CSF administration. Mean neutrophil and monocyte counts (+/- SD) continued to increase reaching a maximum of 72,125/microliters +/- 15,073 (range, 50,915-96,278/microliters) and 3,972/microliters +/- 2,621 (range, 685-8,030/microliters), respectively by day 19. These increased neutrophil and monocyte counts were maintained until the administration of rcG-CSF was stopped. Blood counts returned to normal within 5 days after discontinuing the rcG-CSF. One week after discontinuing treatment, rcG-CSF was started again at 5 micrograms/kg/day subcutaneously. Within 48 hours following administration of rcG-CSF, mean neutrophil counts +/- SD increased from 5,860/microliters +/- 1,819 (range, 3,720-8,650/microliters) to 57,444/microliters +/- 8,173 (range, 43,983-68,278/microliters). Myeloid:erythroid ratios increased from a mean of 1.63:1 on day 1 prior to administration of rcG-CSF to 3.3:1 on day 10 in three dogs for which bone marrow samples were evaluated. Recombinant canine G-CSF did not cause clinically significant toxicosis in any of the dogs.
Obradovich
J E
JE
Comparative Oncology Unit, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins 80523.
Ogilvie
G K
GK
Powers
B E
BE
Boone
T
T
D000818:Animals; D001853:Bone Marrow / Q000187:drug effects; D005260:Female; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000009:adverse effects / Q000494:pharmacology*; D006098:Granulocytes; D006410:Hematopoiesis / Q000187:drug effects*; D007958:Leukocyte Count / Q000662:veterinary; D008297:Male; D009000:Monocytes; D009504:Neutrophils; D011994:Recombinant Proteins / Q000009:adverse effects / Q000494:pharmacology
D011994:Recombinant Proteins; D016178:Granulocyte-Macrophage Colony-Stimulating Factor