Chronic Hepatitis B virus (HBV) is still one of the major reasons for liver related mortality and morbidity all around the world. This study aimed to investigate the possible relationship between the immune system activation and presence, as well as progression, of hepatitis B infection by monitoring the tryptophan degradation and serum neopterin levels in patients with HBV. 110 patients with HBV and 23 healthy subjects were included in the study. The patients had significantly higher neopterin levels and increased kynurenine to tryptophan ratios, which were most probably due to enhanced indoleamine 2,3-dioxygenase (IDO) activity compared to healthy control. A strong positive correlation was found between neopterin levels and IDO activity in patient group. Neopterin levels and IDO activity were markedly increased in patients with histological activity index (HAI) ≥4 compared to HAI<4, and a significant correlation was found between neopterin and HAI. Moreover, there was a significant correlation between albumin levels and IDO activity in HBV patients. These findings suggest that tryptophan degradation results from IFN-γ-induced IDO activation, likewise depletion of albumin synthesis in HBV patients may result from diminished tryptophan availability. In conclusion, based on the study results, serum neopterin levels and IDO activity could provide additional immunological information for monitoring liver histological activity and can be used as prognostic markers in HBV disease.

中文翻译：

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血清新蝶呤水平和IDO活性可能是乙型肝炎存在和发展的标志

慢性乙型肝炎病毒（HBV）仍然是世界范围内与肝脏相关的死亡率和发病率的主要原因之一。这项研究旨在通过监测HBV患者的色氨酸降解和血清新蝶呤水平，研究免疫系统活化与乙型肝炎感染的存在以及进展之间的可能关系。该研究纳入了110名HBV患者和23名健康受试者。患者的新蝶呤水平显着升高，犬尿氨酸与色氨酸之比增加，这很可能是由于与健康对照组相比，吲哚胺2，3-二加氧酶（IDO）活性增强。在患者组中，新蝶呤水平与IDO活性之间存在很强的正相关。与HAI <4相比，组织学活动指数（HAI）≥4的患者新蝶呤水平和IDO活性显着升高，并且新蝶呤和HAI之间存在显着相关性。此外，HBV患者的白蛋白水平与IDO活性之间存在显着相关性。这些发现表明，色氨酸降解是由IFN-γ诱导的IDO激活引起的，同样，HBV患者中白蛋白合成的耗竭也可能是色氨酸的可利用性降低所致。总之，根据研究结果，血清新蝶呤水平和IDO活性可为监测肝脏组织学活性提供额外的免疫学信息，并可作为HBV疾病的预后指标。HBV患者的白蛋白水平与IDO活性之间存在显着相关性。这些发现表明，色氨酸降解是由IFN-γ诱导的IDO激活引起的，同样，HBV患者白蛋白合成的耗竭也可能是色氨酸的利用率降低所致。总之，根据研究结果，血清新蝶呤水平和IDO活性可为监测肝脏组织学活性提供额外的免疫学信息，并可作为HBV疾病的预后指标。HBV患者的白蛋白水平与IDO活性之间存在显着相关性。这些发现表明，色氨酸降解是由IFN-γ诱导的IDO激活引起的，同样，HBV患者白蛋白合成的耗竭也可能是色氨酸的利用率降低所致。总之，根据研究结果，血清新蝶呤水平和IDO活性可为监测肝脏组织学活性提供额外的免疫学信息，并可作为HBV疾病的预后指标。