Mizuta Shumpei, Iwasaki Makoto, Bandai Noriko, Yoshida Saya, Watanabe Asami, Takashima Hiroshi, Ueshimo Takeshi, Bandai Kazuhiro, Fujiwara Kensuke, Hiranuma Naoko, Koba Yusuke, Kawata Takahito, Tamekane Akira, Watanabe Mitsumasa
Department of Clinical Laboratory, Hyogo Prefectural Amagasaki General Medical Center, Amagasaki, Hyogo, Japan.
Laboratory of Hematology, Division of Medical Biophysics, Kobe University Graduate School of Health Sciences, Kobe, Hyogo, Japan.
Cytometry B Clin Cytom. 2024 Jan;106(1):35-44. doi: 10.1002/cyto.b.22148. Epub 2023 Nov 6.
The CD34 CD38 population in bone marrow includes hematopoietic stem/progenitor cells. Recently, in acute myeloid leukemia, the focus has shifted to flow cytometry analysis targeting CD34 CD38 leukemic cells due to their effectiveness in minimal/measurable residual disease detection and prognosis prediction. Nevertheless, the immunophenotype and cell frequency of these cells in the bone marrow, in the absence of leukemic cells, remains unknown. We aimed to evaluate detailed characteristics of CD34 CD38 cells in both normal and leukemic cells by flow cytometry.
We compared the cell frequency and immunophenotype of the CD34 CD38 fraction in the following groups: patients with idiopathic thrombocytopenic purpura and malignant lymphoma as controls (n = 17), post-treatment patients without abnormal blasts (n = 35), and patients with myeloid malignancies (n = 86). The comparison was based on the presence or absence of CD45RA expression, a marker commonly used to prospectively isolate lymphoid-primed cell populations within the CD34 CD38 fraction.
The CD34 CD38 CD45RA cell population exhibited a significant expansion in bone marrow without leukemic cells 1 month after cord blood transplantation and in various type of myeloid malignancies, compared to the control group (p < 0.01). Continuous CD45RA expression and notable expansion of the CD34 CD38 CD45RA population were exclusively observed in myelodysplastic syndrome-related diseases. The CD34 CD38 CD45RA population displayed frequent expression of various markers in both leukemic and non-leukemic cells, in contrast to the CD34 CD38 CD45RA population.
The CD34 CD38 fraction should be carefully evaluated considering the nature of normal hematopoietic precursor cells, their cell frequency and immunophenotype, including CD45RA expression pattern, for improving the accuracy of myeloid malignancy diagnosis.
骨髓中CD34⁺CD38⁻群体包含造血干/祖细胞。近来，在急性髓系白血病中，由于其在微小/可测量残留病检测及预后预测方面的有效性，针对CD34⁺CD38⁻白血病细胞的流式细胞术分析成为研究热点。然而，在无白血病细胞情况下，这些细胞在骨髓中的免疫表型及细胞频率仍不清楚。我们旨在通过流式细胞术评估正常及白血病细胞中CD34⁺CD38⁻细胞的详细特征。
我们比较了以下几组中CD34⁺CD38⁻部分的细胞频率和免疫表型：特发性血小板减少性紫癜和恶性淋巴瘤患者作为对照组（n = 17）、治疗后无异常原始细胞的患者（n = 35）以及髓系恶性肿瘤患者（n = 86）。比较基于CD45RA表达的有无，CD45RA是常用于前瞻性分离CD34⁺CD38⁻部分内淋巴样定向细胞群体的标志物。
与对照组相比，脐血移植后1个月无白血病细胞的骨髓以及各种类型的髓系恶性肿瘤中，CD34⁺CD38⁻CD45RA⁺细胞群体显著扩增（p < 0.01）。仅在骨髓增生异常综合征相关疾病中观察到CD45RA的持续表达以及CD34⁺CD38⁻CD45RA⁺群体的显著扩增。与CD34⁺CD38⁻CD45RA⁻群体相比，CD34⁺CD38⁻CD45RA⁺群体在白血病细胞和非白血病细胞中均频繁表达各种标志物。
为提高髓系恶性肿瘤诊断的准确性，应结合正常造血前体细胞的性质、其细胞频率和免疫表型，包括CD45RA表达模式，仔细评估CD34⁺CD38⁻部分。
