Leukemia inhibitory factor and interleukin-11 promote maturation of murine and human megakaryocytes in vitro.
The growth-promoting activities of optimally stimulating concentrations of leukemia inhibitory factor (LIF) and interleukin-11 (IL-11), a stromal cell-derived cytokine, on megakaryocytes in liquid marrow cultures were compared to interleukin-6 (IL-6), a known megakaryocytes maturation factor. Maximally stimulating concentrations of LIF (25 ng/ml), IL-11 (10 ng/ml), or IL-6 alone (10 ng/ml) promoted an 81, 157, and 153% increase, respectively, in acetylcholinesterase (AchE) activity in murine serum-free cultures compared with controls (n = 5). In combination with 25 U/ml murine interleukin-3 (IL-3), LIF, IL-6, and IL-11 showed increases, respectively, of 35%, 49%, and 174% in AchE activity compared with IL-3 alone (n = 4). Flow cytometric analysis of 4-day-old cultures showed that LIF alone had minimal effect on megakaryocytic ploidy, whereas IL-11 and IL-6 alone markedly augmented high ploidy cells. Enumeration of cells stained for AchE showed that IL-11 increased the numbers of Mks in comparison to LIF, IL-6 or controls by up to 59%. Moreover, a twofold increment in Mk number was noted when IL-11 was used in combination with IL-3 (compared with either IL-3 alone of IL-3+IL-6). Flow cytometric ploidy analysis of 8-day-old human liquid marrow cultures showed that either LIF, IL-11, or IL-6 alone markedly augmented the percentage of 32N cells compared with cultures containing only human IL-3. The data suggest that LIF and IL-11 promote murine and human Mk maturation in vitro, although the effect of IL-11 exceeds that of LIF in mice. Despite the comparable influence of IL-11 and IL-6 on Mk ploidy, IL-11 has the additional characteristic of enhancing the number of Mks, particularly in combination with IL-3.
Burstein
S A
SA
Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City 73190.
Mei
R L
RL
Henthorn
J
J
Friese
P
P
Turner
K
K
D000110:Acetylcholinesterase / Q000378:metabolism; D000818:Animals; D002452:Cell Count / Q000187:drug effects; D002469:Cell Separation; D002478:Cells, Cultured; D016922:Cellular Senescence / Q000187:drug effects; D006131:Growth Inhibitors / Q000494:pharmacology*; D006801:Humans; D017370:Interleukin-11 / Q000494:pharmacology*; D007377:Interleukin-3 / Q000494:pharmacology; D015850:Interleukin-6 / Q000494:pharmacology; D053605:Leukemia Inhibitory Factor; D008222:Lymphokines / Q000494:pharmacology*; D008533:Megakaryocytes / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology; D051379:Mice; D011003:Ploidies
D006131:Growth Inhibitors; D017370:Interleukin-11; D007377:Interleukin-3; D015850:Interleukin-6; C507837:LIF protein, human; D053605:Leukemia Inhibitory Factor; C507838:Lif protein, mouse; D008222:Lymphokines; D000110:Acetylcholinesterase