Stein G H, St Clair J A
Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder 80309.
In Vitro Cell Dev Biol. 1988 May;24(5):381-7. doi: 10.1007/BF02628489.
Human microvascular endothelial cells (HMVEC) from adult adipose tissue were cultured in MCDB 131 medium supplemented with 10% fetal bovine serum. Under these conditions, HMVEC from seven different donors had finite proliferative life spans ranging from 14.5 to 23.5 population doublings (PD), with a mean life span of 19 PD. Addition of 10% conditioned medium from activated human leukocyte cultures (BM Condimed) extended the life span of HMVEC to 31 to 41 PD, with a mean life span of 37 PD. At the end of lifespan, HMVEC cultures both with and without BM Condimed had very low labeling indices (0 to 5% [3H]thymidine labeled nuclei) and consisted of enlarged cells. However, the morphologies of the two types of HMVEC cultures were very different. Untreated HMVEC were polygonal endothelial cells that formed cobblestonelike monolayers with no cell overlapping. In contrast, BM Condimed-treated HMVEC were more elongated, less regularly shaped cells that were not strictly inhibited from overlapping. When old, these cells accumulated numerous vacuoles. The BM Condimed-treated HMVEC expressed Factor VIII antigen, which confirms their identity as endothelial cells. These cells reverted rapidly to the polygonal morphology of untreated HMVEC when they were removed from BM Condimed. Likewise, their proliferative capacity was not extended further once BM Condimed was removed. These results suggest that HMVEC can exist in two distinct morphologic states in which the cells have different finite proliferative life spans.
来自成人脂肪组织的人微血管内皮细胞（HMVEC）在补充有10%胎牛血清的MCDB 131培养基中培养。在这些条件下，来自7个不同供体的HMVEC具有有限的增殖寿命，范围为14.5至23.5个群体倍增（PD），平均寿命为19个PD。添加10%来自活化人白细胞培养物的条件培养基（BM Condimed）可将HMVEC的寿命延长至31至41个PD，平均寿命为37个PD。在寿命结束时，添加和未添加BM Condimed的HMVEC培养物的标记指数都非常低（0至5%的[3H]胸腺嘧啶核苷标记细胞核），且由增大的细胞组成。然而，这两种HMVEC培养物的形态非常不同。未处理的HMVEC是多边形内皮细胞，形成无细胞重叠的鹅卵石样单层。相比之下，经BM Condimed处理的HMVEC是更细长、形状不太规则的细胞，不受严格抑制而重叠。老化时，这些细胞积累大量液泡。经BM Condimed处理的HMVEC表达因子VIII抗原，这证实了它们作为内皮细胞的身份。当从BM Condimed中取出时，这些细胞迅速恢复为未处理的HMVEC的多边形形态。同样，一旦去除BM Condimed，它们的增殖能力就不会进一步延长。这些结果表明，HMVEC可以以两种不同的形态状态存在，其中细胞具有不同的有限增殖寿命。
