Theileria orientalis (T. orientalis) is a bovine protozoal disease similar to malaria in humans. Although the common outcome of malaria in humans and T. orientalis infection in cattle is hepatic disorder, the mechanisms of its development remain unknown. In this study, we investigated hepatocyte injury characterized by accumulation of macrophages with ingested erythrocytes in sinusoid and extramedullary hematopoiesis in cattle and mice experimentally infected with T. orientalis (T. orientalis-infected cattle and T. orientalis-infected mice). Vacuolization of hepatic cells was frequently observed in the vicinity of the aggregated macrophages in the liver sinusoids of T. orientalis-infected mice. A significant percentage of the macrophages accumulated in the liver sinusoids of the severely infected cattle and mice (14.6% and 24.2 to 53.2%, respectively) reacted positively with interleukin-1, interleukin-6 and TNF-α antibodies. Increase in the production of these cytokines was confirmed in T. orientalis-infected cattle and mice by real-time RT-PCR. These findings strongly suggest that increased cytokine production by the macrophages that have phagocytosed T. orientalis-infected erythrocytes causes hepatic disorder in T. orientalis-infected animals.

东方泰勒虫（T. Orientalis）是一种牛原生动物疾病，与人类的疟疾相似。尽管人类中疟疾和牛的东方侧柏感染的常见结局是肝病，但其发展机制仍然未知。在这项研究中，我们调查了肝细胞损伤，其特征在于在实验感染东方三叶草的牛和小鼠（东方三叶草感染的牛和东方三叶草感染的小鼠）中，正弦波和髓外造血过程中吞噬的红细胞巨噬细胞蓄积巨噬细胞。经常在东方血吸虫的肝窦中聚集的巨噬细胞附近观察到肝细胞的真空化被感染的小鼠。在严重感染的牛和小鼠的肝窦中积聚的巨噬细胞中有很大百分比（分别为14.6％和24.2至53.2％）与白细胞介素1，白细胞介素6和TNF-α抗体呈阳性反应。通过实时逆转录-聚合酶链反应（RT-PCR ）证实了在东方锥虫感染的牛和小鼠中这些细胞因子的产生增加。这些发现强烈表明，吞噬吞噬了东方锥虫感染的红细胞的巨噬细胞会增加细胞因子的产生，从而导致东方锥虫感染的动物出现肝脏疾病。