HERITABLE DISORDERS OF CONNECTIVE TISSUE

该科继续进行旨在阐明分子的研究。 结缔组织遗传性疾病的机制，特别是 成骨不全(OI)和Ehler-Danlos(EDS)及其应用 这一信息有助于这些疾病的治疗。 该部门的一个持续兴趣是确定胶原蛋白 OI和EDS患者的基因突变及其相关性研究 突变的类型和位置与疾病的严重程度 结缔组织紊乱。α2(I)胶原链的突变 由本部分和其他实验室确定，提供了其他 支持我们提出的区域模式。 该科有三个主要项目。其中一个主要项目是 选择性反义抑制突变的胶原等位基因 作为一种治疗干预的方法。我们一直在使用 锤头状核酶作为我们的选择性试剂。我们从事的是 用核酶将我们的体外成功转移到培养细胞中 成纤维细胞。我们目前正致力于制造稳定的转染系 已知的胶原蛋白突变，并在瞬时转染报告中 系统。 第二个主要项目是产生一个小鼠模型 非致命性OI。我们已经使用定点突变技术生产了一种 用模仿非致死性人类OI的点突变构建。使 引入了有条件a lox-top-lox构造 进入含有致病基因的外显子之前的内含子 突变。已经用这两种野生型杂交产生了F1小鼠 和表达重组酶的小鼠。鲑鱼体内的重组 产生突变的蛋白表达和严重的OI骨骼表型。 我们一直在开发的第三个主要关注焦点是 OI的骨生物学。我们正在使用培养的成骨细胞来研究 骨细胞修饰和分泌突变的胶原蛋白。我们还在追求 输卵管基质继发性非胶原性异常及其治疗反应 OI成骨细胞对转化生长因子β的刺激。 在临床研究中，我们正在继续我们的生长治疗试验。 OI矮小儿童体内激素对生长发育的影响 刺激、骨密度和骨形态计量学特性。我们是 继续我们在OI的神经学方面的合作兴趣 在最大化OI儿童的身体功能方面， 积极的康复。

The Section has continued its studies aimed at elucidating the molecular mechanisms of heritable disorders of connective tissue, specifically osteogenesis imperfecta (OI) and Ehlers-Danlos (EDS), and at applying this information to the treatment of these disorders. One continuing interest of the Section is to identify the collagen mutations in patients with OI and EDS and determine the relationship between the type and location of the mutation and the severity of the connective tissue disorder. Mutations in the alpha2(I) collagen chain identified by this Section and other labs have provided additional support for the regional model we have proposed. There are three primary projects in the Section. One primary project is to develop selective antisense suppression of the mutant collagen allele as an approach for therapeutic intervention. We have been using hammerhead ribozymes as our selective agent. We are engaged in transferring our in vitro success with ribozymes into cultured fibroblasts. We are currently engaged in making stably transfected lines with known collagen mutations and in a transient transfection reporter system. The second primary project is the generation of a murine model for non-lethal OI. We have used site-directed mutagenesis to produce a construct with a point mutation mimicking non-lethal human OI. To make the construct conditional a lox-stop-lox construct has been introduced into the intron prior to the exon containing the disease-causing mutation. F1 mice have been generated from crosses with both wild type and cre-recombinase expressing mice. Recombination at the lox sites generates mutant protein expression and a severe OI skeletal phenotype. A third major focus of interest which we have been developing is in the bone biology of OI. We are using cultured osteoblasts to study the way bone cells modify and secrete mutant collagen. We are also pursing the secondary non-collagenous abnormalities of OI matrix and the response of OI osteoblasts to TGF-beta stimulation. In clinical studies, we are continuing our treatment trial of growth hormone in short children with OI to determine its effects on growth stimulation, bone density and bone morphometric properties. We are continuing our collaborative interests in the neurological aspects of OI and in maximizing the physical functioning of OI children though aggressive rehabilitation.