Raymond Purves Bone and Joint Research Laboratories, Institute of Bone and Joint Research, Kolling Institute of Medical Research, The Royal North Shore Hospital, University of Sydney, Level 10, Building B6, St. Leonards, NSW, 2065, Australia.
Histochem Cell Biol. 2009 Nov;132(5):491-503. doi: 10.1007/s00418-009-0623-z. Epub 2009 Aug 11.
We evaluated the immunohistochemical distribution of three major proteoglycans of cartilage, i.e., aggrecan, versican and perlecan vis-a-vis collagens I and II in the developing human spine of first-trimester foetuses. Aggrecan and perlecan were prominently immunolocalised in the cartilaginous vertebral body rudiments and to a lesser extent within the foetal intervertebral disc. In contrast, versican was only expressed in the developing intervertebral disc interspace. Using domain-specific monoclonal antibodies against the various modules of versican, we discovered the V0 isoform as the predominant form present. Versican immunolocalisations conducted with antibodies directed to epitopes in its N and C termini and GAG-alpha and GAG-beta core protein domains provided evidence that versican in the nucleus pulposus was either synthesised devoid of a G3 domain or this domain was proteolytically removed in situ. The V0 versican isoform was localised with prominent fibrillar components in the annular lamellae of the outer annulus fibrosus. Perlecan was a notable pericellular proteoglycan in the annulus fibrosus and nucleus pulposus but poorly immunolocalised in the marginal tissues of the developing intervertebral disc, apparently delineating the intervertebral disc-vertebral body interface region destined to become the cartilaginous endplate in the mature intervertebral disc. The distribution of collagens I and II in the foetal spine was mutually exclusive with type I present in the outer annulus fibrosus, marginal tissues around the vertebral body rudiment and throughout the developing intervertebral disc, and type II prominent in the vertebral rudiment, absent in the outer annulus fibrosus and diffusely distributed in the inner annulus fibrosus and nucleus pulposus. Collectively, our findings suggest the existence of an intricate and finely balanced interplay between various proteoglycans and collagens and the spinal cell populations which synthesise and assemble these components during spinal development.
我们评估了三种主要软骨蛋白聚糖，即聚集蛋白聚糖、神经蛋白聚糖和蛋白聚糖，以及 I 型和 II 型胶原在人胚胎脊柱发育中的免疫组织化学分布。聚集蛋白聚糖和蛋白聚糖在软骨椎体原基中显著免疫定位，在胎儿椎间盘中有一定程度的免疫定位。相比之下，神经蛋白聚糖仅在发育中的椎间盘间隙中表达。使用针对神经蛋白聚糖各种模块的特异性单克隆抗体，我们发现 V0 同种型是主要存在形式。用针对其 N 和 C 末端和 GAG-α和 GAG-β核心蛋白结构域表位的抗体进行神经蛋白聚糖免疫定位，提供了证据表明，核髓核中的神经蛋白聚糖要么在没有 G3 结构域的情况下合成，要么该结构域在原位被蛋白水解去除。V0 神经蛋白聚糖同种型在纤维环的环状层中与明显的纤维状成分定位。蛋白聚糖是纤维环和核髓核中显著的细胞周蛋白聚糖，但在发育中的椎间盘边缘组织中免疫定位不佳，显然划定了椎间盘-椎体界面区域，该区域将成为成熟椎间盘的软骨终板。胎儿脊柱中 I 型和 II 型胶原的分布是相互排斥的，I 型存在于纤维环外、椎体原基周围的边缘组织和整个发育中的椎间盘，而 II 型在椎体原基中突出，在纤维环外不存在，在纤维环内和核髓核中弥漫分布。总之，我们的发现表明，在脊柱发育过程中，各种蛋白聚糖和胶原与合成和组装这些成分的脊柱细胞群体之间存在着复杂而精细的平衡相互作用。
