Dodd J, Jessell T M
J Neurosci. 1985 Dec;5(12):3278-94. doi: 10.1523/JNEUROSCI.05-12-03278.1985.
Cell surface carbohydrates are thought to play important roles in the development and differentiation of mammalian cells. In previous studies we have found that one population of dorsal root ganglion (DRG) neurons is specified by the expression of complex globoseries oligosaccharides (Dodd, J., D. Solter, and T. M. Jessell (1984) Nature 311: 469-472; Jessell, T. M., and J. Dodd (1985) Philos. Trans. R. Soc. Lond. (Biol.) 308: 271-281). We now report that monoclonal antibodies (MAbs) directed against backbone structures of lactoseries oligosaccharides define antigens present in the cytoplasm of a second, anatomically and functionally distinct subset of DRG neurons. Lactoseries carbohydrate structures identified by MAb A5 are restricted to small- and intermediate-diameter DRG neurons with central projections in the superficial dorsal horn of the rat spinal cord. The distribution of labeled terminals suggests that many of the DRG neurons that express lactoseries carbohydrates are likely to convey nociceptive information. More complex galactose- and fucose-substituted lactoseries structures recognized by MAbs LD2, KH10, TC6, TD10, LA4, and anti-Lewis a are segregated on subsets of DRG neurons that differ in their expression of substance P, somatostatin, and fluoride-resistant acid phosphatase and in their laminar termination in the superficial dorsal horn. The majority of lactoseries carbohydrate antigens identified in the cytoplasm of DRG neurons are also expressed on the surface of subsets of DRG neurons in culture. These studies establish that structurally defined carbohydrate differentiation antigens specify the majority of primary sensory neurons with cutaneous receptive fields. Moreover, lactoseries carbohydrate structures similar or identical to those expressed on neonatal DRG neurons in culture have been implicated in cell-cell interactions at early stages of preimplantation embryonic development. Our observations suggest strategies for testing the hypothesis that carbohydrates present on the surface of subsets of DRG neurons play a role in cell interactions that contribute to the laminar organization of sensory afferents in the developing spinal cord.
细胞表面碳水化合物被认为在哺乳动物细胞的发育和分化中发挥重要作用。在先前的研究中，我们发现一群背根神经节（DRG）神经元由复杂的球系列寡糖的表达所决定（多德，J.，D. 索尔特，和T. M. 杰塞尔（1984年）《自然》311：469 - 472；杰塞尔，T. M.，和J. 多德（1985年）《伦敦皇家学会哲学学报》（生物）308：271 - 281）。我们现在报告，针对乳糖系列寡糖主链结构的单克隆抗体（MAb）确定了存在于DRG神经元的第二个在解剖学和功能上不同的亚群细胞质中的抗原。由单克隆抗体A5识别的乳糖系列碳水化合物结构仅限于在大鼠脊髓背角浅层有中央投射的小直径和中等直径DRG神经元。标记终末的分布表明，许多表达乳糖系列碳水化合物的DRG神经元可能传递伤害性信息。由单克隆抗体LD2、KH10、TC6、TD10、LA4和抗Lewis a识别的更复杂的半乳糖和岩藻糖取代的乳糖系列结构在DRG神经元亚群上是分开的，这些亚群在P物质、生长抑素和耐氟酸性磷酸酶的表达以及在背角浅层的层状终末方面存在差异。在DRG神经元细胞质中鉴定出的大多数乳糖系列碳水化合物抗原也在培养的DRG神经元亚群表面表达。这些研究表明，结构明确的碳水化合物分化抗原确定了大多数具有皮肤感受野的初级感觉神经元。此外，与培养的新生DRG神经元上表达的那些相似或相同的乳糖系列碳水化合物结构已被认为在植入前胚胎发育早期的细胞间相互作用中起作用。我们的观察结果提出了一些策略，用于检验DRG神经元亚群表面存在的碳水化合物在有助于发育中的脊髓感觉传入层状组织的细胞相互作用中起作用这一假设。
