Reddi A H, Anderson W A
J Cell Biol. 1976 Jun;69(3):557-72. doi: 10.1083/jcb.69.3.557.
Transplantation of collagenous matrix from the rat diaphyseal bone to subcutaneous sites resulted in new bone formation by an endochondral sequence. Functional bone marrow develops within the newly formed ossicle. On day 1, the implanted matrix was a discrete conglomerate with fibrin clot and polymorphonuclear leukocytes. By day 3, the leukocytes disappeared, and this event was followed by migration and close apposition of fibroblast cell surface to the collagenous matrix. This initial matrix-membrane interaction culminated in differentiation of fibroblasts to chondroblasts and osteoblasts. The calcification of the hypertrophied chondrocytes and new bone formation were correlated with increased alkaline phosphatase activity and 45Ca incorporation. The ingrowth of capillaries on day 9 resulted in chondrolysis and osteogenesis. Further remodelling of bony trabeculae by osteoclasts resulted in an ossicle of cancellous bone. This was followed by emergence of extravascular islands of hemocytoblasts and their differentiation into functional bone marrow with erythropoietic and granulopoietic elements and megakaryocytes in the ossicle. The onset and maintenance of erythropoiesis in the induced bone marrow were monitored by 59Fe incorporation into protein-bound heme. These findings imply a role for extracellular collagenous matrix in cell differentiation.
将大鼠骨干骨的胶原基质移植到皮下部位，会通过软骨内成骨序列形成新骨。功能性骨髓在新形成的小骨内发育。第1天，植入的基质是一个含有纤维蛋白凝块和多形核白细胞的离散团块。到第3天，白细胞消失，随后成纤维细胞表面迁移并紧密贴附于胶原基质。这种初始的基质-膜相互作用最终导致成纤维细胞分化为软骨细胞和成骨细胞。肥大软骨细胞的钙化和新骨形成与碱性磷酸酶活性增加和45Ca掺入相关。第9天毛细血管长入导致软骨溶解和成骨。破骨细胞对骨小梁的进一步重塑导致松质骨小骨形成。随后，血母细胞的血管外岛出现，并在小骨内分化为具有红细胞生成、粒细胞生成成分和巨核细胞的功能性骨髓。通过将59Fe掺入蛋白质结合血红素中监测诱导骨髓中红细胞生成的开始和维持。这些发现表明细胞外胶原基质在细胞分化中起作用。
