Rosen C J, Verault D, Steffens C, Cheleuitte D, Glowacki J
St. Joseph Hospital, Bangor, ME 04401, USA.
Endocrine. 1997 Aug;7(1):77-80. doi: 10.1007/BF02778068.
Human marrow was obtained as material discarded during total hip replacement and was established in culture with phenol red-free alpha-MEM with 10% fetal bovine serum (FBS) and antibiotics. Insulin-like growth factor I (IGF-I) and its binding proteins were secreted by human marrow cells, in amounts that increased with time in culture. Western ligand blotting showed that insulin-like growth factor binding protein-3 (IGFBP-3) accounted for the majority (approximately 75%) of the secreted binding proteins. Evidence for marrow secretion of BP-3 protease was found by electrophoretic analysis of mixtures of radiolabeled IGFBP-3 and marrow-conditioned media. The amount of constitutive secretion of IGFBP-3 increased with age of the subject (r = 0.97, p = 0.0058). A notable exception was marrow from a postmenopausal women on estrogen replacement therapy (ERT) at the time of surgery; her marrow secreted 89.3 ng/mL after 14 d in vitro, only 38% of the IGFBP-3 that was secreted by cultures from two age-matched peers (208.8 and 285.2 ng/mL). This in vivo effect of estrogen was matched by an in vitro experiment in which 10(-8) M 17-beta estradiol suppressed IGFBP-3 to 60% of the constitutive level. In all cultures of marrow from postmenopausal women, IL-1 beta suppressed IGFBP-3 secretion to either undetectable levels or levels between 11% and 35% of control. Thus, human bone marrow cultures demonstrate components of the skeletal IGF regulatory system: IGF-I, IGF-binding proteins, and evidence of IGFBP-3 proteolysis. These results provide evidence of regulation by both systemic (age, estrogen status) and cytokine (IL-1 beta) factors.
人类骨髓取自全髋关节置换术中废弃的材料，在含10%胎牛血清（FBS）和抗生素的无酚红α-MEM培养基中进行培养。胰岛素样生长因子I（IGF-I）及其结合蛋白由人类骨髓细胞分泌，分泌量随培养时间增加。蛋白质免疫印迹法显示，胰岛素样生长因子结合蛋白-3（IGFBP-3）占分泌的结合蛋白的大部分（约75%）。通过对放射性标记的IGFBP-3与骨髓条件培养基混合物的电泳分析，发现了骨髓分泌BP-3蛋白酶的证据。IGFBP-3的组成型分泌量随受试者年龄增加而增加（r = 0.97，p = 0.0058）。一个显著的例外是一名接受雌激素替代疗法（ERT）的绝经后妇女在手术时的骨髓；她的骨髓在体外培养14天后分泌89.3 ng/mL，仅为两名年龄匹配的同龄人（208.8和285.2 ng/mL）培养物分泌的IGFBP-3的38%。雌激素的这种体内作用在体外实验中得到了验证，其中10^(-8) M的17-β雌二醇将IGFBP-3抑制至组成型水平的60%。在所有绝经后妇女骨髓培养物中，IL-1β将IGFBP-3分泌抑制至检测不到的水平或对照水平的11%至35%之间。因此，人类骨髓培养物展示了骨骼IGF调节系统的组成部分：IGF-I、IGF结合蛋白以及IGFBP-3蛋白水解的证据。这些结果提供了全身（年龄、雌激素状态）和细胞因子（IL-1β）因素调节的证据。
