巴贝西虫感染黑线仓鼠生物学特性的变化

目的建立巴贝西虫感染的黑线仓鼠模型,明确感染后黑线仓鼠生物学特性的变化规律,为巴贝西虫病的检测与防治提供基础数据资料。方法腹腔注射含巴贝西虫的血液感染黑线仓鼠,感染的第0、2、4、6、8、10、12、14、16、23、30、37天每次取5只动物采集抗凝血和全血,制备血涂片,通过吉姆萨染色检测虫体繁殖情况;分离血液总DNA,用REAL-TIME PCR检测巴贝西虫的在宿主体内的繁殖规律;用全自动生理生化检测仪测定血液生理生化指标;处死动物后分别采集心、肝、脾、肺、肾等器官,称重测定脏器系数;用ELISA法检测感染动物血清中IL-2浓度。结果感染后第4天黑线仓鼠体内的巴贝西虫数量最多,之后整体呈下降趋势,在第12天有一个短暂升高。感染动物的脏器系数变化最大的属于肝脏和脾脏,心、肺和肾脏系数在整个感染期内稍有波,均在正常值范围内。感染动物的血细胞均有波动,在第10、23天两次达峰值,其中白细胞变化最为剧烈;检测到变化的血液生化指标在第12天达峰值。感染动物血清中的IL-2在第10天达峰值,之后连续下降。结论感染巴贝西虫的黑线仓鼠具有典型的蜱传寄生虫病特点,病原侵入一周内达繁殖顶峰,且病原可在宿主体内长期潜伏。宿主免疫响应在第2周达到峰值,与免疫相关的脏器及血细胞有明显的应激反应。据此,可有针对性的开展巴贝西虫病的诊断与防治。

Biological characteristics of Chinese hamster infected with Babesia

Objective To establish a Chinese hamster model of babesia infection, to find the changing pattern of organs and biochemical parameters in Chinese hamster infected with Babesia, and to promote the detection and treatment of babesiosis.Methods Healthy 5-week old Chinese hamsters were infected by intraperitoneal injection of blood containing Babesia. Blood samples were collected at 0, 2, 4, 6, 8, 10, 12, 14, 16, 23, 30, and 37 days after infection from 5 hamsters at each time point. Blood smears were prepared to detect the parasites using Giemsa staining. ELISA assay was employed to test the IL-2 concentration. The blood biochemical indexes were detected using an automatic biochemical analyzer. DNA was extracted from the whole blood and REAL-TIME RCR was performed to determine the reproduction of Babesia. Aftert the animals were sacrificed, the heart, lung, spleen, liver, and kidney were taken to analyze the changes of organ coefficients. Results The highest level of Babesia in the hamsters occurred on day 4 after the Babesia injection, and then showing a decreasing tendency. However, there was a transient increase on the 12^th day after infection. The liver and spleen displayed most extensive response to the infection showing hepatomegaly and splenomegaly, but the variation of heart and kidneys coefficients was within the norm. There were prominent changes of blood cells, especially leucocytes, with two peaks at day 10 and 23 after the Babesia infection. The peak changes of blood biochemical indexes occurred at day 12 after infection. The concentration of serum IL-2 reached a peak on the 10th day after infection. Conclusions The Chinese hamsters display typical characteristics of tick-borne diseases such as hepatomegaly and splenomegaly. The immunological system is activated along with the infection and reaches a highest stage in the second week. Afterwards the Babesia can live in the hamster body for a long period of time. The results of this study provide useful information supporting further studies on the detection, treatment and prevention of Babesiosis.