MARKER PROTEINS FOR MUSCLE CELL TRANSPLANTATION STUDIES

尽管进行了深入的研究，但肌肉组织中的分子缺陷 人类和动物组织的营养不良还有待鉴定。 是 然而，可以想象的是，一种成功的治疗方法可能是使用 方法，避免了对这种知识的需要。 正在进行的工作， 几个实验室表明，在引入正常的肌肉细胞后， 正常的细胞核被整合到宿主体内 纤维及其表型的表达。 然而， 假设的混合细胞和与改进的纤维结构的相关性， 由于缺乏独立的标记物， 营养不良核 我们已经确定了三种与疾病无关的肌球蛋白等位基因变体 轻链-1（I、II和III型）在快速白色肌纤维中的表达 适合用作标记蛋白的家养鸡。 建议： (i)开发I型纯合的正常鸡品系， III LC-1变体（所有营养不良品系的鸟偶然地 对于II型形式是纯合的）。 (ii)以开发针对每种变体的单克隆抗体。 (iii)通过培养中的免疫显微镜，使用两种 LC 1类型不同的正常心肌细胞，LC 1是否扩散受限 在肌纤维中。 一个积极的发现将允许正常和 在随后的移植中，杂交纤维内的营养不良核 实验 (iv)使用免疫显微镜和正常和营养不良细胞 LC 1变异的不同类型，正常和 营养不良的细胞混合在培养物中。 (v)为了在体内使用免疫显微镜测定杂交的程度， 引入表达一种LC 1的正常细胞后的纤维形成 在表达第二种基因的营养不良组织中进行分型，并将其与 纤维组织学和超微结构的任何改善。 (vi)如果LC 1在纤维中的扩散被证明是有限的， 杂交纤维中正常和营养不良细胞核的鉴定（参见（iii）） 以上），比较纤维组织学和超微结构的区域， 分别由正常和营养不良的细胞核维持的杂交纤维。 (vii)使用LC 1变体和正常和营养不良肌球蛋白重链， 链（HC）由我们区分，使用类似的程序来确定 LC 1和HC是否以相似的程度占据肌纤维。

Despite intensive research, the molecular defects underlying the muscular dystrophies of human and animal tissues have yet to be identified. It is conceivable, however, that a successful therapy might be developed using a method which circumvents the need for this knowledge. Ongoing work from several laboratories indicates that, on introduction of normal muscle cells into diseased muscle, the normal nuclei are incorporated into the host fibers and their phenotype expressed. However, identification of the hypothesized hybrid cells and correlation with improved fiber structure has not been possible because of the lack of independent markers for normal and dystrophic nuclei. We have identified three nondiseased-related, allelic variants of myosin light chain-1 (types I, II and III) in the fast white muscle fibers of domestic chickens suitable for use as marker proteins. It is proposed: (i) to develop strains of noromal chickens homozygous for the type I and III LC-1 variants (birds of all dystrophic strains are fortuitously homozygous for the type II form). (ii) to develop monoclonal antibodies specific for each of the variants. (iii) to determine, by immunomicroscopy in culture, using two kinds of normal myocytes differing in LC1 types, whether LC1 is limited in diffusion in the myofiber. A positive finding will permit location of normal and dystrophic nuclei within a hybrid fiber in subsequent transplantation experiments. (iv) to determine, using immunomicroscopy and normal and dystrophic cell types differing in LC1 variants, the survival advantages of normal and dystrophic cells mixed in culture. (v) to determine in vivo, using immunomicroscopy, the extent of hybrid fiber formation following introduction of normal cells expressing one LC1 type into dystrophic tissue expressing a second, and to correlate this with any improvement in fiber histology and ultrastructure. (vi) if LC1 diffusion in the fiber proves to be limited, permitting identification of normal and dystrophic nuclei in hybrid fibers (see (iii) above), to compare the fiber histology and ultrastructure in regions of hybrid fibers maintained by normal and dystrophic nuclei respectively. (vii) using the LC1 variants and the normal and dystrophic myosin heavy chains (HC) distinguished by us, to use similar procedures to determine whether LC1 and HC occupy the myofiber to similar extents.