Peterson A C, Bray G M
J Cell Biol. 1984 Nov;99(5):1831-7. doi: 10.1083/jcb.99.5.1831.
Multiple discontinuities are observed in the basal laminas of Schwann cells in mature dystrophic mice. To explore the pathogenesis of this abnormality we have exploited a dystrophic in equilibrium shiverer mouse chimera preparation in which both the basal lamina phenotype and the genotype of myelin-forming Schwann cells can be determined. If the basal lamina abnormality were to arise from an intrinsic deficiency of the dystrophic Schwann cell itself, only those Schwann cells of dystrophic genotype could express the mutant phenotype, whereas the coexisting population of shiverer Schwann cells should express typically normal basal laminas. No such distinction was observed; rather both dystrophic and shiverer Schwann cells were found to express relatively normal basal laminas and two pathogenetic mechanisms remain theoretical possibilities. The dystrophic Schwann cell population may be intrinsically defective but also may be rescued by obtaining the normal product of the dy locus synthesized by the coexisting shiverer cells. Alternatively, an extra Schwann cell deficiency existing within dystrophic mice may be normalized by shiverer cells and the normal intrinsic potential of both dystrophic and shiverer Schwann cells can then be realized. Regardless of the exact mechanism underlying these findings, some extracellularly mediated influence, emanating in vivo from shiverer cells, is capable of ameliorating the basal lamina deficiency typically expressed by dystrophic Schwann cells.
在成熟的营养不良小鼠中，观察到施万细胞基膜存在多处连续性中断。为了探究这种异常的发病机制，我们利用了一种处于平衡状态的营养不良性颤抖小鼠嵌合体模型，在该模型中，可以确定形成髓鞘的施万细胞的基膜表型和基因型。如果基膜异常是由营养不良的施万细胞自身内在缺陷引起的，那么只有那些具有营养不良基因型的施万细胞才能表达突变表型，而共存的颤抖小鼠施万细胞群体应该表达典型的正常基膜。但未观察到这种差异；相反，发现营养不良的施万细胞和颤抖小鼠的施万细胞都表达相对正常的基膜，两种发病机制仍然只是理论上的可能性。营养不良的施万细胞群体可能存在内在缺陷，但也可能通过获得共存的颤抖小鼠细胞合成的dy位点的正常产物而得到挽救。或者，营养不良小鼠体内存在的额外施万细胞缺陷可能通过颤抖小鼠细胞而正常化，然后营养不良和颤抖小鼠施万细胞的正常内在潜力都可以实现。无论这些发现背后的确切机制是什么，源自颤抖小鼠细胞的一些细胞外介导的影响能够改善营养不良的施万细胞通常表现出的基膜缺陷。
