Department of Pathology, Faculty of Medicine, Prince of Songkla University, Hat Yai, Songkhla, Thailand.
Molecular Medicine Graduate Program, Faculty of Science, Mahidol University, Bangkok, Thailand.
PeerJ. 2024 Sep 20;12:e18054. doi: 10.7717/peerj.18054. eCollection 2024.
Ineffective erythropoiesis (IE) is the primary cause of anemia and associated pathologies in -thalassemia. The characterization of IE is imbalance of erythroid proliferation and differentiation, resulting in increased erythroblast proliferation that fails to differentiate and gives rise to enucleate RBCs. MicroRNAs (miRs) are known to play important roles in hematopoiesis. miR-155 is a multifunctional molecule involved in both normal and pathological hematopoiesis, and its upregulation is observed in patients with -thalassemia/HbE. However, the expression and function of miR-155, especially in -thalassemia, have not yet been explored.
To study miR-155 expression in thalassemia, erythroblast subpopulations, CD45-CD71Ter-119 and CD45-CD71Ter-119 were collected from thalassemic bone marrow. Additionally, a two-phase culture of mouse bone marrow erythroid progenitor cells was performed. Expression of miR-155 and predicted mRNA target genes, , and , were determined by quantitative reverse transcription (qRT)-polymerase chain reaction (PCR) and normalized to small nucleolar RNA (snoRNA) 202 and glyceraldehyde-3-phosphate dehydrogenase (GAPDH), respectively. To investigate the effect of miR-155 expression, erythroblasts were transfected with miR-inhibitor and -mimic in order to elevate and eliminate miR-155 expression, respectively. Erythroid cell differentiation was evaluated by Wright-Giemsa staining and flow cytometry.
miR-155 was upregulated, both and , during erythropoiesis in -thalassemic mice. Our study revealed that gain- and loss of function of miR-155 were involved in erythroid proliferation and differentiation, and augmented proliferation and differentiation of thalassemic mouse erythroblasts may be associated with miR-155 upregulation. miR-155 upregulation in -thalassemic mice significantly increased the percentage of basophilic and polychromatic erythroblasts. Conversely, a significant decrease in percentage of basophilic and polychromatic erythroblasts was observed in -thalassemic mice transfected with anti-miR-155 inhibitor. We also examined the mRNA targets (, and ) of miR-155, which indicated that is a valid target gene of miR-155 that regulates erythroid differentiation.
miR-155 regulates IE in -thalassemia via expression controlling erythroblast proliferation and differentiation.
无效造血（IE）是 - 地中海贫血中贫血及相关病变的主要原因。IE 的特征是红系增殖和分化失衡，导致红系前体细胞增殖增加，但无法分化，并产生无核 RBC。已知 microRNAs（miRs）在造血中发挥重要作用。miR-155 是一种参与正常和病理造血的多功能分子，在 - 地中海贫血/HbE 患者中观察到其上调。然而，miR-155 的表达和功能，特别是在 - 地中海贫血中的表达和功能尚未得到探索。
为了研究地中海贫血中的 miR-155 表达，从地中海贫血骨髓中收集红系亚群 CD45-CD71Ter-119 和 CD45-CD71Ter-119。此外，还进行了小鼠骨髓红系祖细胞的两相培养。通过定量逆转录（qRT）-聚合酶链反应（PCR）测定 miR-155 和预测的 mRNA 靶基因、、和的表达，并分别用小核仁 RNA（snoRNA）202 和甘油醛-3-磷酸脱氢酶（GAPDH）进行归一化。为了研究 miR-155 表达的影响，用 miR-抑制剂和 miR- mimic 转染红细胞，分别升高和消除 miR-155 的表达。通过 Wright-Giemsa 染色和流式细胞术评估红细胞分化。
miR-155 在 - 地中海贫血小鼠的红细胞生成过程中上调，和均上调。我们的研究表明，miR-155 的功能获得和丧失参与了红细胞的增殖和分化，而地中海贫血小鼠红细胞的增殖和分化增强可能与 miR-155 的上调有关。- 地中海贫血小鼠 miR-155 的上调显著增加了碱性和多染性红细胞的百分比。相反，在转染抗 miR-155 抑制剂的 - 地中海贫血小鼠中，碱性和多染性红细胞的百分比显著降低。我们还检查了 miR-155 的 mRNA 靶标（、和），结果表明是 miR-155 调控红细胞分化的有效靶基因。
miR-155 通过调控表达控制红系前体细胞的增殖和分化，调节 - 地中海贫血中的 IE。
