Armstrong David J, Hiscott Paul, Batterbury Mark, Kaye Stephen
Unit of Ophthalmology, Department of Medicine, UCD, Daulby Street, University of Liverpool, L69 3GA, Liverpool, UK.
Int J Biochem Cell Biol. 2002 Jun;34(6):588-93. doi: 10.1016/s1357-2725(01)00157-1.
Members of the thrombospondin (TSP) family of proteins have been implicated in wound healing. The cells of the corneal stroma (keratocytes) are capable of synthesising TSP-1 in a wound repair phenotype, but do not appear to produce the protein in the normal human adult cornea. We employed reverse-transcriptase polymerase chain reaction (RT-PCR) to determine whether human corneal stromal cells can express TSPs other than TSP-1. Cultured keratocytes contained messenger RNA (mRNA) for TSP-2 and TSP-3 (in addition to TSP-1), but not for TSP-4 or cartilage oligomeric matrix protein (COMP; TSP-5). Keratocytes in the normal cornea contained mRNA for TSP-1 but not for other TSPs. The distribution of keratocyte TSP-2 and TSP-3 immunoreactivity had some similarities to that of TSP-1 and, like TSP-1, neither protein could be detected in the cells of the normal corneal stroma. The observations suggest that keratocytes in wound repair phenotype produce TSP-2 and TSP-3 in addition to TSP-1. TSPs may play a pivotal role in corneal stromal repair and, since TSP-1 and TSP-2 have anti-angiogenic properties, may also have a function in regulating the avascularity of the central cornea.
血小板反应蛋白（TSP）家族蛋白的成员与伤口愈合有关。角膜基质细胞（角膜细胞）能够在伤口修复表型中合成TSP-1，但在正常成人角膜中似乎不产生该蛋白。我们采用逆转录聚合酶链反应（RT-PCR）来确定人角膜基质细胞是否能表达除TSP-1之外的TSPs。培养的角膜细胞含有TSP-2和TSP-3的信使核糖核酸（mRNA）（除了TSP-1），但不含有TSP-4或软骨寡聚基质蛋白（COMP；TSP-5）的mRNA。正常角膜中的角膜细胞含有TSP-1的mRNA，但不含有其他TSPs的mRNA。角膜细胞TSP-2和TSP-3免疫反应性的分布与TSP-1有一些相似之处，并且与TSP-1一样，在正常角膜基质细胞中均检测不到这两种蛋白。这些观察结果表明，处于伤口修复表型的角膜细胞除了产生TSP-1外，还产生TSP-2和TSP-3。TSPs可能在角膜基质修复中起关键作用，并且由于TSP-1和TSP-2具有抗血管生成特性，它们也可能在调节角膜中央无血管状态中发挥作用。
