Golde W T, Dolan M C
Division of Vector-Borne Infectious Diseases, Centers for Disease Control and Prevention, Fort Collins, Colorado 80522, USA.
Infect Immun. 1995 Dec;63(12):4795-801. doi: 10.1128/iai.63.12.4795-4801.1995.
The original isolate of Borrelia burgdorferi, strain B31, can be maintained in vitro indefinitely. A number of studies have demonstrated that there are recognizable changes in the genetic composition of the spirochete after more than 60 passages. We have maintained B31 in the natural zoonotic cycle of transmission of infection between laboratory mice and laboratory-reared Ixodes ticks. To determine whether similar changes occur in the natural transmission cycle, we reisolated strain B31 from mouse skin at the fifth zoonotic cycle. This reisolated derivative had the same infectivity as the parent B31 strain, had lost the 8-kb supercoiled plasmid present in B31, and induced a gross serum antibody response indistinguishable from the B31 immune response. Analysis of antigen expression with monoclonal antibodies generated against B31, however, showed differential expression of a subset of antigens between B31 and the isolated derivative.
伯氏疏螺旋体的原始菌株B31能够在体外无限传代培养。多项研究表明，该螺旋体在传代60次以上后，其基因组成会发生可识别的变化。我们通过实验室小鼠和实验室饲养的硬蜱之间的自然人畜共患病感染传播循环来保存B31菌株。为了确定在自然传播循环中是否会发生类似的变化，我们在第五次人畜共患病循环时从小鼠皮肤中重新分离出B31菌株。这种重新分离出的衍生物与亲本B31菌株具有相同的感染性，丢失了B31中存在的8kb超螺旋质粒，并诱导出与B31免疫反应无法区分的总体血清抗体反应。然而，用针对B31产生的单克隆抗体分析抗原表达时，发现B31与分离出的衍生物之间存在一部分抗原的差异表达。
