Abstract
ABSTRACT: During states of increased demand, neonatal host defense is characterized by dysregulation of granulopoiesis, resulting in a high incidence of neutropenia. This study investigated the modulation of neonatal rat hematopoiesis by 14-d administration of recombinant human (rh) IL-6, rh-granulocyte-colony stimulating factor (G-CSF), or sequential combination of rhIL-6 and rhG-CSF. Specifically, newborn Sprague-Dawley rats were treated with either rhIL-6 (5 μg/kg/d for 14 d), rhG-CSF (5 μg/kg/d for 14 d), rhIL-6 for 7 d followed by rhG-CSF for 7 d, PBS/BSA for 7 d followed by rhG-CSF for 7 d, or PBS/BSA for 14 d. RhIL-6 alone significantly increased the peripheral platelet count during the latter part of the 2nd wk of administration (d 13: 980 ± 42 versus 716 ± 23 × 103/mm3) (p = < 0.001) (mean ± SEM). Treatment with rhIL-6 for 7 d followed by rhG-CSF significantly increased the peripheral neutrophil count compared with 7 d of PBS/BSA and 7 d of G-CSF (d 14 absolute neutrophil count 4888 ± 12 versus 2720 ± 317/mm3) (p = < 0.05). Similarly, sequential rhIL-6/rhG-CSF significantly increased the d-14 bone marrow neutrophil storage pool (9873 ± 882 versus 3564 ± 159/mm3) (p = < 0.005). Lastly, sequential rhIL-6/rhG-CSF induced the highest increase in bone marrow (p < 0.01) and liver/spleen CFU-GM pool (p < 0.001) compared with any other treatment group. These studies suggest that rhIL-6 alone is associated with a significant increase in the neonatal platelet count. The sequential combination of rhIL-6 followed by rhG-CSF may also induce significant increases in neonatal peripheral neutrophilia, bone marrow neutrophil storage pools, and bone marrow and liver/spleen myeloid progenitor pools. This sequential combination has been demonstrated to enhance neonatal hematopoiesis.
Similar content being viewed by others
Article PDF
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Cairo, M., Plunkett, J., Nguyen, A. et al. Sequential Administration of Interleukin-6 and Granulocyte-Colony Stimulating Factor in Newborn Rats: Modulation of Newborn Granulopoiesis and Thrombopoiesis. Pediatr Res 30, 554–559 (1991). https://doi.org/10.1203/00006450-199112000-00013
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1203/00006450-199112000-00013