Hematopoietic origin of fibroblasts/myofibroblasts:

its pathophysiologic implications

Makio Ogawa, Amanda C. LaRue, and Christopher J. Drake

  Tissue fibroblasts/myofibroblasts play a key role in growth factor　　　secretion, matrix deposition, and matrix degradation, and therefore are important in many pathologic processes. Regarding the origin of tissue fibroblasts/myofibroblasts, a number of recent in vivo transplantation studies have suggested the bone marrow as the source of fibroblasts/myofibroblasts in liver, intestine, skin, and lung. Because bone marrow cells are thought to contain 2 types of stem cells (ie, hematopoietic stem cells [HSCs] and mesenchymal stemcells), it is important to determine which type of stem cells is the source of fibroblasts/myofibroblasts. To address this issue,we have carried out a series of studies of tissue reconstitution by single HSCs. By transplanting clones derived from single HSCs expressing transgenic enhanced green fluorescent protein, we found that fibroblasts/myofibroblasts in many organs and tissues are derived from HSCs. This brief note summarizes these findings and discusses clinical and experimental perspectives generated by this newly identified differentiation pathway of HSCs. (Blood. 12,2006;108:2893-2896)

成纤维细胞与成肌纤维细胞的造血干细胞来源：它的病理生理意义

     组织中的成纤维细胞或是成肌纤维细胞在许多病理过程中发挥重要的作用，它们分泌生长因子，基质沉积与降解。关于组织中成纤维细胞与成肌纤维细胞的起源，最近许多体内移植研究表明，在肝脏，肠，皮肤和肺中的成纤维细胞与成肌纤维细胞来源于骨髓。因为骨髓细胞中包含两中类型的细胞（造血干细胞和间充质干细胞），探明成纤维细胞与成肌纤维细胞来源于骨髓细胞中的那种细胞是很有意义的。为了阐明这个问题，我们进行了一系列组织重建用单一的造血干细胞。通过移植能够表达绿色荧光蛋白的单一造血干细胞克隆，我们发现许多组织和器官中的成纤维细胞与成肌纤维细胞来源于造血干细胞。这个简要的阐述总结了这些发现，以及由造血干细胞新的分化途径所引起的临床与实验室远景的讨论。