Campbell J H, Efendy J L, Han C, Girjes A A, Campbell G R
Centre for Research in Vascular Biology, University of Queensland, Brisbane, Australia.
J Vasc Res. 2000 Sep-Oct;37(5):364-71. doi: 10.1159/000025752.
This study utilized both in vivo and in vitro techniques to investigate whether cells of bone marrow origin can differentiate into smooth muscle-like cells (myofibroblasts) with contractile filaments and proteins. Female C57BL/6 mice expressing the Ly5.2 antigen on the surface of their haemopoietic cells had four pieces of silastic tubing (3 x 0.5 mm outer diameter) or boiled blood clot (2-3 mm diameter) placed in their peritoneal cavity. After 3, 5, 7 and 14 days (n = 4/group) the implants were removed and those that had remained free-floating were processed for light microscopy, immunohistochemistry and electron microscopy. In the first 3-5 days, rounded cells adhered to the entire surface of the tubing then flattened. These cells stained with fluoresceinated antibodies to Ly5.2 showing that they were derived from haemopoietic cells. By 14 days the cells had become elongated and multilayered in a collagen matrix, forming a thick tissue capsule around the tubing or boiled clot. They contained contractile filaments and stained with antibodies to alpha-smooth muscle actin but no longer stained for Ly5.2. A separate set of female C57BL/6 Ly5.2 mice were X-irradiated to destroy bone marrow then immediately transfused with 10(6) nucleated bone marrow cells taken from the femur and tibia of a congenic strain of male mice expressing the Ly5.1 allele. Eight of the female mice with successful engraftment (80-99%) had silastic tubing implanted in the peritoneal cavity. After 14 days, in situ hybridization with Y chromosome probe confirmed the male donor, and thus bone marrow, origin of the elongated cells that formed the capsule. In vitro studies showed that cells of the murine macrophage cell lines RAW 264.7 and J774 express alpha-smooth muscle actin after exposure to the cytokine gamma-interferon in vitro. These data show that bone marrow-derived cells can differentiate into smooth muscle-like cells and raises the possibility that blood-derived cells may contribute to the development of fibro-proliferative vascular diseases such as atherosclerosis.
本研究采用体内和体外技术，以探究骨髓来源的细胞是否能分化为具有收缩性细丝和蛋白质的平滑肌样细胞（肌成纤维细胞）。在造血细胞表面表达Ly5.2抗原的雌性C57BL/6小鼠，将四段硅橡胶管（外径3×0.5毫米）或煮沸的血凝块（直径2 - 3毫米）置于其腹腔内。3、5、7和14天后（每组n = 4），取出植入物，将那些仍漂浮的植入物进行光镜、免疫组织化学和电子显微镜检查。在最初的3 - 5天，圆形细胞粘附于硅橡胶管的整个表面，然后变扁平。这些细胞用荧光素标记的抗Ly5.2抗体染色，表明它们来源于造血细胞。到14天时，细胞在胶原基质中变得细长且多层，在硅橡胶管或煮沸的血凝块周围形成厚的组织囊。它们含有收缩性细丝，并用抗α平滑肌肌动蛋白抗体染色，但不再用抗Ly5.2抗体染色。另一组雌性C57BL/6 Ly5.2小鼠经X射线照射以破坏骨髓，然后立即输注取自表达Ly5.1等位基因的同基因雄性小鼠股骨和胫骨的10(6)个有核骨髓细胞。8只移植成功（80 - 99%）的雌性小鼠在腹腔内植入硅橡胶管。1
