Eto T, Akashi K, Harada M, Shibuya T, Takamatsu Y, Teshima T, Niho Y
First Department of Internal Medicine, Faculty of Medicine, Kyushu University, Fukuoka, Japan.
Br J Haematol. 1992 Nov;82(3):508-14. doi: 10.1111/j.1365-2141.1992.tb06460.x.
We studied the biological characteristics of CD7+ acute myelogenous leukaemia (AML). We diagnosed nine out of 88 consecutive AML cases as CD7+ AML based on myeloperoxidase positivity and surface antigen expression. In eight of these nine cases more than 20% of leukaemic blasts were found to coexpress both CD7 and a myeloid-associated antigen, CD33, by a two-colour flow-cytometric assay, while in the remaining case more than 90% of blasts were positive for CD7 and myeloperoxidase. CD7+ AML was most frequently observed in M1 among AML subtypes according to the FAB classification. An early stage-specific antigen, CD34 was also expressed on leukaemic blasts from eight of these nine cases. Neither the T-cell receptor (TcR)-beta nor the TcR-gamma gene was clonally rearranged in any of the cases. We then studied the proliferative responses to stimulation by various growth factors. Among interleukin-3 (IL-3), granulocyte/macrophage colony-stimulating factor (GM-CSF), and granulocyte-CSF (G-CSF), IL-3 showed the strongest stimulatory effect on DNA synthesis and leukaemic blast colony formation in 8/9 and 6/8 CD7+ AML cases examined, respectively. On the other hand, the strongest stimulatory effect exerted by IL-3 on blast colony formation was observed in only six out of the 33 CD7- AML cases examined. Furthermore, CD7+ AML blasts could proliferate in response to stem cell factor (SCF); SCF alone showed stimulatory effects on blast colony formation (7/8 cases), and in 5/7 SCF-responding cases, stimulatory effects of SCF were more potent than those of IL-3. In addition, SCF enhanced blast colony formation synergistically with IL-3 in four of these seven cases. These data suggest that progenitor cells of CD7+ AML may possess the biological properties characteristic of immature haematopoietic stem cells.
我们研究了CD7⁺急性髓性白血病（AML）的生物学特性。基于髓过氧化物酶阳性和表面抗原表达，我们在连续88例AML病例中诊断出9例为CD7⁺ AML。在这9例中的8例中，通过双色流式细胞术检测发现超过20%的白血病原始细胞同时共表达CD7和一种髓系相关抗原CD33，而在其余1例中超过90%的原始细胞CD7和髓过氧化物酶呈阳性。根据FAB分类，CD7⁺ AML在AML亚型中最常出现在M1型。一种早期阶段特异性抗原CD34也在这9例中的8例白血病原始细胞上表达。所有病例中T细胞受体（TcR）-β和TcR-γ基因均未发生克隆性重排。然后我们研究了对各种生长因子刺激的增殖反应。在白细胞介素-3（IL-3）、粒细胞/巨噬细胞集落刺激因子（GM-CSF）和粒细胞集落刺激因子（G-CSF）中，IL-3分别对所检测的8/9和6/8例CD7⁺ AML病例的DNA合成和白血病原始细胞集落形成显示出最强的刺激作用。另一方面，在所检测的33例CD7⁻ AML病例中，只有6例观察到IL-3对原始细胞集落形成有最强的刺激作用。此外，CD7⁺ AML原始细胞可对干细胞因子（SCF）产生增殖反应；单独的SCF对原始细胞集落形成有刺激作用（7/8例），并且在5/7例对SCF有反应的病例中，SCF的刺激作用比IL-3更强。此外，在这7例中的4例中，SCF与IL-3协同增强原始细胞集落形成。这些数据表明，CD7⁺ AML的祖细胞可能具有未成熟造血干细胞的生物学特性。
