Carlo-Stella C, Tabilio A, Regazzi E, Garau D, La Tagliata R, Trasarti S, Andrizzi C, Vignetti M, Meloni G
Department of Hematology, University of Parma, Italy.
Bone Marrow Transplant. 1997 Sep;20(6):465-71. doi: 10.1038/sj.bmt.1700916.
Since reduced marrow cellularity and prolonged pancytopenia following autologous bone marrow transplantation (ABMT) have been frequently observed in patients with acute myelogenous leukemia (AML) included in the AML10 GIMEMA/EORTC trial, the question was raised to what extent hematopoietic and microenvironmental progenitor cells were involved in these patients. Marrow hematopoietic progenitors were investigated by a short-term methylcellulose assay quantitating multipotent CFU-Mix, erythroid BFU-E and granulocyte-macrophage CFU-GM, as well as a long-term assay quantitating long-term culture-initiating cells (LTC-IC). The marrow microenvironment was studied by evaluating the incidence of fibroblastoid progenitors (CFU-F) and the capacity of stromal layers to support allogeneic hematopoietic progenitors. As compared to normal controls (n = 57), AML patients (n = 26) showed a statistically significant reduction of the mean (+/-s.e.m.) number of CFU-Mix (5.3 +/- 0.6 vs 0.8 +/- 0.2, P < or = 0.0001), BFU-E (68 +/- 5 vs 20 +/- 4, P < or = 0.0001), CFU-GM (198 +/- 11 vs 144 +/- 15, P < or = 0.008), and LTC-IC (302 +/- 46 vs 50 +/- 8, P < or = 0.001). The mean (+/-s.e.m.) incidence of marrow CFU-F was not significantly reduced as compared to normal controls (48 +/- 6 vs 52 +/- 7, P < or = 0.73). Seventeen AML stromal layers were tested for their capacity to support the growth of allogeneic hematopoietic progenitors. Seven samples failed to support any progenitor cell growth, seven had a significantly lower supportive activity as compared to normal stromal layers (13 +/- 5 vs 249 +/- 56, P < or = 0.002), whereas three cultures could not be analyzed due to contamination. In conclusion, induction and consolidation regimens used in AML patients of the AML10 protocol induce a markedly defective in vitro growth of primitive hematopoietic progenitors and a severe functional defect of marrow stroma. The association of hematopoietic with microenvironmental damage might play a key role in the delayed hematopoietic regeneration observed following ABMT in patients of the AML10 trial.
由于在AML10 GIMEMA/EORTC试验纳入的急性髓性白血病（AML）患者中，经常观察到自体骨髓移植（ABMT）后骨髓细胞减少和全血细胞减少持续时间延长，因此有人提出造血祖细胞和微环境祖细胞在这些患者中受累的程度问题。通过短期甲基纤维素试验对多能CFU-Mix、红系BFU-E和粒-巨噬细胞CFU-GM进行定量，以及通过长期试验对长期培养起始细胞（LTC-IC）进行定量，来研究骨髓造血祖细胞。通过评估成纤维细胞样祖细胞（CFU-F）的发生率和基质层支持同种异体造血祖细胞的能力，来研究骨髓微环境。与正常对照（n = 57）相比，AML患者（n = 26）的CFU-Mix平均（±标准误）数量有统计学显著降低（5.3±0.6对0.8±0.2，P≤0.0001）、BFU-E（68±5对20±4，P≤0.0001）、CFU-GM（198±11对144±15，P≤0.008）和LTC-IC（302±46对50±8，P≤0.001）。与正常对照相比，骨髓CFU-F的平均（±标准误）发生率没有显著降低（48±6对52±7，P≤0.73）。对17个AML基质层支持同种异体造血祖细胞生长的能力进行了测试。7个样本未能支持任何祖细胞生长，7个样本与正常基质层相比支持活性显著降低（13±5对249±56，P≤0.002），而3个培养物因污染无法分析。总之，AML10方案中AML患者使用的诱导和巩固方案导致原始造血祖细胞的体外生长明显缺陷以及骨髓基质的严重功能缺陷。造血损伤与微环境损伤的关联可能在AML10试验患者ABMT后观察到的造血再生延迟中起关键作用。
