Clonorchis sinensis infection could trigger strong immune responses in mice and humans. However, whether the C.sinensis infection has an impact on arthritis is unknown. Here we investigated the effect of C.sinensis infection on type II collagen-induced arthritis in BALB/c mice. The mice were firstly infected with 45 C.sinensis metacercariae by oral gavage. Four weeks later, arthritis in mice was induced by type II collagen. Joint inflammation with severe redness and swelling in hind paws was observed in type II collagen-induced arthritis (CIA) mice. Besides, the physical activity was significantly reduced, but the respiratory exchange ratio was increased in CIA mice. Compared with CIA mice, C.sinensis infection could increase the severity of arthritis in CIA mice, based on the results of disease score and pathological changes. Compared to CIA mice, increased neutrophils and Ly6Chi monocytes, decreased B cells and CD4+T cells, were found in C.sinensis infected CIA mice. Besides these, C.sinensis infected mice also displayed significantly higher levels of serum IL-4 and IL-17 than those in CIA mice. Taken together, our data suggest that C.sinensis infection have a bad effect on arthritis, and could induce the abnormality of the immune response in mice with CIA.

中文翻译：

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华支睾吸虫感染对Ⅱ型胶原诱导的关节炎小鼠免疫反应的影响

中华支睾吸虫感染可在小鼠和人类中引发强烈的免疫反应。但是，尚不清楚中华梭菌感染是否对关节炎有影响。在这里，我们调查了中华。感染对BALB / c小鼠II型胶原诱导的关节炎的影响。首先通过管饲法将小鼠感染了45个中华.。四周后，II型胶原蛋白诱发了小鼠关节炎。在II型胶原诱导的关节炎（CIA）小鼠中观察到关节发炎，后足严重发红和肿胀。此外，CIA小鼠的体力活动明显降低，但呼吸交换率却增加了。与CIA小鼠相比，根据疾病评分和病理变化的结果，中华球菌感染可增加CIA小鼠的关节炎严重程度。与CIA老鼠相比，在感染中华球藻的CIA小鼠中发现嗜中性粒细胞和Ly6Chi单核细胞增加，B细胞和CD4 + T细胞减少。除此之外，感染了中华线虫的小鼠还显示出比CIA小鼠更高的血清IL-4和IL-17水平。综上所述，我们的数据表明，中华线虫感染对关节炎具有不良影响，并可能诱发CIA小鼠的免疫反应异常。