The pivotal role of interleukin 6 in formation and function of hematopoietically active murine long-term bone marrow cultures.
The multifunctional cytokine interleukin 6 (IL-6) is involved in the regulation of inflammatory and immune responses, and influences many bone and bone marrow functions. In this report we show high concentrations of IL-6 in the supernatant of murine long-term bone marrow cultures (LTBMC). The concentration increases following medium change peaking 12 h later. IL-6 plays a critical role in the generation and maintenance of myelopoiesis in LTBMC. The addition of monoclonal anti-IL-6 antibody to culture significantly suppresses myeloid cell production. IL-6 is also necessary for stromal layer development and the initiation of myelopoiesis in LTBMC. Horse sera (HS) containing low concentrations of IL-6 did not support LTBMC stromal layer development or myeloid cell production, whereas those with high concentrations did. LTBMC initially set up with horse serum containing high IL-6 concentration produced higher concentrations of colony-stimulating activity and IL-6 at the fifth week after culture initiation than those with low concentrations. The ability of a deficient serum to support myelopoiesis could be improved by the addition of recombinant IL-6 to culture. Similarly, the addition of an anti-IL-6 antibody to culture impaired the ability of a HS to initiate and support myelopoiesis in LTBMC. These results suggest that IL-6 is one of the factors that play an essential role in the formation and function of hematopoietically active LTBMC.
Hauser
S P
SP
Department of Medicine, University of Arkansas for Medical Sciences, Little Rock, USA.
Kajkenova
O
O
Lipschitz
D A
DA
D000818:Animals; D000911:Antibodies, Monoclonal / Q000494:pharmacology; D001853:Bone Marrow / Q000187:drug effects / Q000378:metabolism*; D001854:Bone Marrow Cells; D002478:Cells, Cultured; D003115:Colony-Stimulating Factors / Q000378:metabolism; D003470:Culture Media; D005260:Female; D006736:Horses; D015850:Interleukin-6 / Q000276:immunology / Q000378:metabolism* / Q000502:physiology*; D007700:Kinetics; D051379:Mice; D008810:Mice, Inbred C57BL; D011994:Recombinant Proteins / Q000494:pharmacology; D017154:Stromal Cells / Q000502:physiology; D013997:Time Factors
D000911:Antibodies, Monoclonal; D003115:Colony-Stimulating Factors; D003470:Culture Media; D015850:Interleukin-6; D011994:Recombinant Proteins