Department of Orthopaedic Surgery, Carolinas Medical Center, Charlotte, NC 28232, USA.
Histol Histopathol. 2010 Nov;25(11):1431-6. doi: 10.14670/HH-25.1431.
Pregnancy-associated plasma protein-A (PAPP-A), a metalloproteinase expressed by a number of cell types, has the important role of cleaving insulin-like growth factor (IGF)-binding protein-2, -4 and -5 in the extracellular matrix and thus freeing up IGF and making it available to cells. The objective of the present study was to utilize immunocytochemical analysis to determine the proportion of PAPP-A-positive cells in a large group of disc specimens which covered the spectrum of changes from relatively healthy Thompson grade II discs to extremely degenerate grade V discs. Work was approved by our institutional human subjects review board. Seventy-two intervertebral disc specimens were assessed for immunocytochemical localization of PAPP-A and the proportion of positive cells determined in the outer annulus, inner annulus and nucleus pulposus. The percentage of PAPP-A positive cells in both the outer and inner annulus correlated significantly with increasing stages of disc degeneration in a fashion which was not dependent upon subject age. There was no significant difference in the percentage of PAPP-A positive cells in the inner annulus of herniated vs non-herniated sites, or in the outer annulus of herniated vs non-herniated sites. Data reported here point to the importance of additional work to elucidate the role of PAPP-A in intervertebral disc aging and degeneration.
妊娠相关血浆蛋白 A（PAPP-A）是一种由多种细胞类型表达的金属蛋白酶，具有在细胞外基质中切割胰岛素样生长因子（IGF）结合蛋白-2、-4 和 -5 的重要作用，从而释放 IGF 并使其可供细胞利用。本研究的目的是利用免疫细胞化学分析来确定大量椎间盘标本中 PAPP-A 阳性细胞的比例，这些标本涵盖了从相对健康的 Thompson 分级 II 椎间盘到极度退变的分级 V 椎间盘的一系列变化。本工作已获得我们机构人类受试者审查委员会的批准。对 72 个椎间盘标本进行了 PAPP-A 的免疫细胞化学定位评估，并确定了外层环、内层环和髓核中阳性细胞的比例。外层环和内层环中 PAPP-A 阳性细胞的百分比与椎间盘退变的阶段呈显著正相关，与受试者年龄无关。在突出和非突出部位的内层环或突出和非突出部位的外层环中，PAPP-A 阳性细胞的百分比没有显著差异。这里报告的数据表明，需要进一步的工作来阐明 PAPP-A 在椎间盘老化和退变中的作用。
