Department of Medicine, Helsinki University Central Hospital, Helsinki, Finland.
Clin Lymphoma Myeloma Leuk. 2012 Oct;12(5):363-5. doi: 10.1016/j.clml.2012.06.001. Epub 2012 Sep 13.
Indoleamine 2,3-dioxygenase (IDO) activity and expression is increased in many hematological malignancies, but has not been previously studied in chronic lymphocytic leukemia (CLL). We determined IDO activity and expression in 49 patients with CLL. We found that IDO activity is increased in CLL. This may have some influence on CLL progression.
Indoleamine 2,3-dioxygenase (IDO) is an enzyme involved in the catabolism of tryptophan, suppressing T-cell activity. IDO activity and expression are increased in many malignant diseases, including hematological malignancies. IDO expression can mediate immunotolerance to tumors. IDO activity and expression have not previously been studied in chronic lymphocytic leukemia (CLL).
We measured IDO activity by calculating the kynurenine-tryptophan (kyn-trp) ratio. IDO and IDO2 gene expression was determined by using real-time polymerase chain reaction (PCR).
In patients with CLL, the serum kyn-trp ratio--reflecting increased IDO activity--was significantly higher compared with controls, but in peripheral blood mononuclear cells (PBMCs)--mainly representing malignant B cells--the expression of genes encoding IDO and IDO2 enzymes was reduced.
Increased IDO activity in patients with CLL may affect disease progression, although it originates from cells other than malignant B cells.
色氨酸 2,3-双加氧酶（IDO）的活性和表达在许多血液恶性肿瘤中增加，但在慢性淋巴细胞白血病（CLL）中尚未进行研究。我们测定了 49 例 CLL 患者的 IDO 活性和表达。我们发现 CLL 中 IDO 活性增加。这可能对 CLL 的进展有一定影响。
色氨酸 2,3-双加氧酶（IDO）是一种参与色氨酸分解代谢的酶，抑制 T 细胞活性。IDO 的活性和表达在许多恶性疾病中增加，包括血液恶性肿瘤。IDO 表达可介导对肿瘤的免疫耐受。IDO 活性和表达在慢性淋巴细胞白血病（CLL）中尚未进行研究。
我们通过计算犬尿氨酸-色氨酸（kyn-trp）比值来测量 IDO 活性。通过实时聚合酶链反应（PCR）测定 IDO 和 IDO2 基因表达。
与对照组相比，CLL 患者的血清 kyn-trp 比值（反映 IDO 活性增加）显著升高，但在外周血单核细胞（主要代表恶性 B 细胞）中，编码 IDO 和 IDO2 酶的基因表达降低。
CLL 患者 IDO 活性增加可能影响疾病进展，尽管它起源于恶性 B 细胞以外的细胞。
