Wolf N S, Arora R K
Mech Ageing Dev. 1982 Oct;20(2):127-40. doi: 10.1016/0047-6374(82)90064-1.
Transplanted devascularized mouse femurs and spleens or spleens ligated in situ all undergo a period of massive necrosis followed by a period of cellular regeneration and reconstitution of tissue components. This renewal of stromal tissue is endogenous to the organ and proliferates inward from a thin rim of surviving cells. Components of the femoral or splenic stroma constitute a hemopoietic microenvironment whose functions include the lodgment, commitment to differentiation and support of the proliferation of hemopoietic stem cells and their differentiating descendents. By using measures of the ability to support hemopoiesis, and the histological appearance of the reconstituted hemopoietic organs, it was shown that the degree of regeneration of the stroma was inversely related to its chronological age. Thus, although age-related changes in stromal cells are not readily demonstrable in hemopoietic tissue during a normal lifespan, they are in process and can be made obvious under anoxic conditions causing cell death followed by an unusual demand for cell replication. Key cellular components of such aged tissues apparently have either lessened resistance to anoxia or a reduction in replicative potential or both. The second alternative interpretation suggests an analogy in vivo to mesenchymal-cell clonal attenuation observed in vitro.
移植去血管化的小鼠股骨和脾脏或原位结扎的脾脏，都会经历一段大量坏死期，随后是细胞再生期以及组织成分的重建期。这种基质组织的更新是器官内源性的，从一层薄薄的存活细胞边缘向内增殖。股骨或脾脏基质的成分构成了造血微环境，其功能包括造血干细胞及其分化后代的 lodgment、分化承诺和增殖支持。通过使用支持造血能力的测量方法以及重建造血器官的组织学外观，发现基质的再生程度与其 chronological 年龄呈负相关。因此，尽管在正常寿命期间造血组织中基质细胞的年龄相关变化不易显现，但它们正在发生，并且在导致细胞死亡随后对细胞复制有异常需求的缺氧条件下会变得明显。这种老化组织的关键细胞成分显然对缺氧的抵抗力降低或复制潜力降低，或者两者兼而有之。第二种替代解释表明在体内类似于体外观察到的间充质细胞克隆衰减。
