Oehler L, Foedinger M, Koeller M, Kollars M, Reiter E, Bohle B, Skoupy S, Fritsch G, Lechner K, Geissler K
Department of Laboratory Medicine, University of Vienna, St Anna Children's Cancer Research Institute, Austria.
Blood. 1997 Feb 15;89(4):1147-53.
Spontaneous growth of myeloid colonies (colony-forming unit-granulocyte-macrophage [CFU-GM]) can be observed in methylcellulose cultures containing peripheral blood mononuclear cells (PB-MNCs) and is supposedly caused by the release of colony-stimulating factors (CSF) by accessory cells. Because of its cytokine synthesis-inhibiting effects on T lymphocytes and monocytes, interleukin-10 (IL-10) may be a potential candidate for indirect modulation of hematopoiesis. We studied the effect of recombinant human IL-10 (rhIL-10) on spontaneous growth of myeloid colonies derived from human PB-MNCs. A total of 10 ng/mL of IL-10 almost completely inhibited spontaneous CFU-GM proliferation (by 95.1%; P < .001, n = 7) in unseparated PB-MNCs. This effect was dose-dependent and specific, because a neutralizing anti-IL-10 antibody was able to prevent IL-10-induced suppression of CFU-GM growth. Spontaneous CFU-GM growth, which required the presence of both monocytes (CD14+ cells) and T lymphocytes (CD3+ cells), was also greatly suppressed by a neutralizing anti-granulocyte-macrophage CSF (GM-CSF) antibody but was only slightly or not at all inhibited by antibodies against G-CSF or IL-3. Moreover, IL-10-suppressed colony growth could be completely restored by the addition of exogenous GM-CSF. Using semiquantitative polymerase chain reaction, we were able to show that GM-CSF transcripts that spontaneously increased in PB-MNCs within 48 hours of culture were markedly reduced by the addition of IL-10. Inhibiton of GM-CSF production in PB-MNCs by IL-10 was also confirmed at the protein level by measuring GM-CSF levels in suspension cultures. Our findings suggest that autonomous CFU-GM growth, resulting from an interaction of monocytes and T lymphocytes, is mainly caused by endogenous GM-CSF release and can be profoundly suppressed by the addition of exogenous IL-10. Considering the strong inhibitory action of IL-10 on GM-CSF production and spontaneous cell growth in vitro, this cytokine may be useful in myeloid malignancies in which autocrine and/or paracrine mechanisms involving GM-CSF are likely to play a pathogenetic role.
在含有外周血单个核细胞（PB - MNCs）的甲基纤维素培养物中可观察到髓系集落（集落形成单位 - 粒细胞 - 巨噬细胞[CFU - GM]）的自发生长，推测这是由辅助细胞释放集落刺激因子（CSF）所致。由于白细胞介素 - 10（IL - 10）对T淋巴细胞和单核细胞具有细胞因子合成抑制作用，它可能是间接调节造血的潜在候选因子。我们研究了重组人IL - 10（rhIL - 10）对源自人PB - MNCs的髓系集落自发生长的影响。总共10 ng/mL的IL - 10几乎完全抑制了未分离的PB - MNCs中CFU - GM的自发增殖（抑制率达95.1%；P <.001，n = 7）。这种作用具有剂量依赖性且具有特异性，因为一种中和性抗IL - 10抗体能够阻止IL - 10诱导的CFU - GM生长抑制。自发的CFU - GM生长需要单核细胞（CD14 +细胞）和T淋巴细胞（CD3 +细胞）同时存在，一种中和性抗粒细胞 - 巨噬细胞CSF（GM - CSF）抗体也能显著抑制其生长，但抗G - CSF或IL - 3抗体对其抑制作用轻微或无抑制作用。此外，添加外源性GM - CSF可使IL - 10抑制的集落生长完全恢复。使用半定量聚合酶链反应，我们能够证明，培养48小时内PB - MNCs中自发增加的GM - CSF转录本在添加IL - 10后显著减少。通过测量悬浮培养物中的GM - CSF水平，在蛋白质水平上也证实了IL - 10对PB - MNCs中GM - CSF产生的抑制作用。我们的研究结果表明，单核细胞与T淋巴细胞相互作用导致的CFU - GM自主生长主要是由内源性GM - CSF释放引起的，添加外源性IL - 10可对其产生显著抑制。鉴于IL - 10在体外对GM - CSF产生和细胞自发生长具有强烈的抑制作用，这种细胞因子可能对髓系恶性肿瘤有用，在髓系恶性肿瘤中，涉及GM - CSF的自分泌和/或旁分泌机制可能发挥致病作用。
