小鼠模型中伯氏疏螺旋体组织载量的定量研究

目的用实时荧光定量PCR确定伯氏疏螺旋体感染小鼠模型不同组织的病原体载量。方法培养低传代伯氏疏螺旋体至对数生长期，稀释为1×10^5／ml。为建立伯氏疏螺旋体感染小鼠模型，于每只小鼠皮内注射菌液100μl，在证实感染成功后，于第12天和第18天分别取不同组织，提取总DNA，用实时荧光定量PCR分别测定组织中的螺旋体flaB基因拷贝数，并标准化为每10^6β-肌动蛋白所对应的flaB拷贝数（螺旋体数）。对不同组织的螺旋体载量进行统计学处理，确定不同组织螺旋体载量差异是否有统计学意义。结果在所检测的4种代表性组织中，膀胱螺旋体载量在两个典型时间点均最高，皮肤和关节次之，心脏最低。结论伯氏疏螺旋体感染小鼠后，不同组织螺旋体载量差异有统计学意义。组织螺旋体载量与组织损伤程度无密切关系。

Quantitative study of Borrelia burgdorferi burdens in different murine tissues

Objective To quantify the burden of Borrelia burgdogrferi in different representative tissues from the murine host by real time quantitative PCR（Q-PCR）. Methods Low-passage B.burgdorferi was cultivated to logarithmic growth phase, and diluted to a concentration of 1 × 10^5/ml for experimental use. To establish a B.burgdoferi-infected murine model, mice were injected 100μl diluted culture intradermally in the back. After artificial infection was confirmed, mice were sacrificed at 12 d and 18 d post-infection in CO2 box. Samples from skin, joint, heart and urine bladder were collected aseptically and frozen at -80 ℃, and total DNA was extracted. B.burgdogferi flaB was quantified by Q-PCR. Data were analyzed statistically to determine if bacterial burdens in various tissues showed a significant difference. Results spirochete burden was the highest in the urine bladder, medium in the skin and joint, lowest in the heart. Conclusion There was significant difference among spirochete burden in various tissues. Spirochete burden in the tissue was not positively related to the severity of this tissue.