San Antonio J D, Lander A D, Wright T C, Karnovsky M J
Department of Pathology, Harvard Medical School, Boston, Massachusetts.
J Cell Physiol. 1992 Jan;150(1):8-16. doi: 10.1002/jcp.1041500103.
In investigating the role of cell-extracellular matrix interactions in cell adhesion and growth control, the effects of heparin on cell-collagen interactions were examined. Exponentially growing Balb/c-3T3 fibroblasts were radiolabelled with 3H-thymidine and detached from tissue culture surfaces using EDTA, and cell attachment to various types of collagen substrata was assayed in the presence or absence of heparin or other glycosaminoglycans (GAGs) or dextran sulfate (40 K). Cells attached readily (70-90%) to films of types I and V, but not to type III collagen. The number of cells bound to types I and V collagen films was inhibited by 10-50% when heparin was present from 0.1-100 micrograms/ml. Cell-collagen attachment was also inhibited by dextran sulfate, and to a lesser extent by dermatan sulfate, but chondroitin sulfates A and C and hyaluronic acid showed no effect. Heparin was active even at early time points in the adhesion assay, suggesting it may disrupt cell-collagen attachment. To study the effects of heparin in modulating cell growth on collagen, growth arrested cells cultured on type I collagen films were serum stimulated in the presence of heparin or other GAGs for 3 days. Growth was inhibited (greater than 40%) only by heparin and dextran sulfate. Interaction of heparin fragments (Mr less than or equal to 6KD) with type I collagen was analyzed by affinity co-electrophoresis (Lee and Lander, 1991) and showed higher affinity heparin binding to native as compared with denatured collagen. These data suggest that sites within native collagen may mediate Balb cell-collagen and heparin-collagen interactions, and such interactions may be relevant towards understanding heparin's antiproliferative activity in vivo and in vitro.
在研究细胞与细胞外基质相互作用在细胞黏附及生长控制中的作用时，检测了肝素对细胞与胶原蛋白相互作用的影响。对数生长期的Balb/c - 3T3成纤维细胞用³H - 胸腺嘧啶核苷进行放射性标记，并用乙二胺四乙酸（EDTA）使其从组织培养表面脱离，然后在有或无肝素、其他糖胺聚糖（GAGs）或硫酸葡聚糖（40K）存在的情况下，检测细胞对各种类型胶原蛋白底物的黏附情况。细胞很容易（70 - 90%）黏附到I型和V型胶原蛋白膜上，但不黏附到III型胶原蛋白膜上。当存在0.1 - 100微克/毫升的肝素时，黏附到I型和V型胶原蛋白膜上的细胞数量受到10 - 50%的抑制。硫酸葡聚糖也抑制细胞与胶原蛋白的黏附，硫酸皮肤素的抑制作用较小，但硫酸软骨素A和C以及透明质酸没有作用。即使在黏附试验的早期时间点，肝素也有活性，这表明它可能破坏细胞与胶原蛋白的黏附。为了研究肝素在调节细胞在胶原蛋白上生长方面的作用，将在I型胶原蛋白膜上培养的生长停滞细胞在有肝素或其他GAGs存在的情况下用血清刺激3天。只有肝素和硫酸葡聚糖抑制生长（超过40%）。通过亲和共电泳（Lee和Lander，1991）分析了肝素片段（分子量小于或等于6KD）与I型胶原蛋白的相互作用，结果显示与变性胶原蛋白相比，肝素与天然胶原蛋白的结合亲和力更高。这些数据表明，天然胶原蛋白中的位点可能介导Balb细胞与胶原蛋白以及肝素与胶原蛋白的相互作用，并且这种相互作用可能与理解肝素在体内和体外的抗增殖活性有关。
