CELLULAR BIOLOGY OF CHOLESTEATOMA

耳胆脂瘤起源于鼓膜，其后遗症 中耳炎。胆脂瘤是进行性的上皮性病变， 破坏中耳，有时是内耳的骨质结构。一次 已确诊的胆脂瘤只能通过手术根治 二期中耳再造术。这样做的长期目标是 研究计划是为了了解导致 胆脂瘤的发生、发展和骨质破坏。是这样的 了解可能导致非手术预防的策略。 以及对这种疾病的管理。 这个应用程序的具体目标是研究细胞 三种细胞类型在胆脂瘤中的生物学意义 进展：角质形成细胞、成纤维细胞和破骨细胞。这个 沙土鼠回缩袋胆脂瘤模型将用于 研究1)细胞角蛋白的变化和表达，2)细胞角蛋白的表达 纤溶酶原激活物级联成分，以及3)白介素1家族 在发生胆脂瘤的角质形成细胞中。量化 免疫组织化学、组织形态计量学、~3H-胸腺嘧啶核苷掺入、~3H-TdR 尿苷掺入和原位杂交将用于检测 关于角质形成细胞的假说。成纤维细胞的培养倾向 从诱发性胆脂瘤向合成基底膜的侵袭 与对照组成纤维细胞相比。来自这些培养物的条件培养液 将测试小鼠头盖骨器官的骨吸收活性 文化体系。 先前的研究表明，局部因子(S)是在骨骼产生的 导致破骨细胞前体募集和激活的表面 破骨细胞。将在体内诱导局部骨吸收 加压水泡模型。~3H-尿苷掺入骨细胞将 被用作RNA转录增加的衡量标准。一个潜在的角色 白介素1在体内和体外的破骨活性 通过试图阻止诱导的、局限性的骨吸收进行调查 与新近发现的白细胞介素2受体拮抗剂。这个 组织型和尿激酶型纤溶酶原激活剂的潜力 影响破骨细胞吸收将使用小鼠来确定 颅骨器官培养。

Aural cholesteatomas arise from the tympanic membrane as a sequela of otitis media. Cholesteatomas are progressive, epithelial lesions which destroy the bony structures of the middle and sometimes inner ear. Once established, cholesteatomas can only be managed by surgical eradication and secondary middle ear reconstruction. The long term objective of this research program is to understand the cellular mechanisms which lead to the development, progression and bone destruction of cholesteatomas. Such an understanding may lead to strategies for the non-surgical prevention and management of this disease. The specific aims of this application are to investigate the cellular biology of three cell types that appear to be important in cholesteatoma progression: the KERATINOCYTE, the FIBROBLAST, and the OSTEOCLAST. The gerbilline retraction pocket cholesteatoma model will be used to investigate the alteration and the expression of 1) cytokeratins, 2) the plasminogen activator cascade components, and 3) the interleukin-1 family within keratinocytes in developing cholesteatomas. Quantitative immunohistochemistry, histomorphometry, 3H-thymidine incorporation, 3H- uridine incorporation and in situ hybridization will be used to test hypotheses regarding KERATINOCYTES. The propensity of cultured FIBROBLASTS from induced cholesteatomas to invade synthetic basement membrane will be compared to control fibroblasts. Conditioned medium from these cultures will be tested for bone resorbing activity in the mouse calvarial organ culture system. Prior studies have indicated that local factor(s) are produced at the bone surface which lead to recruitment of OSTEOCLAST precursors and activation of osteoclasts. Localized bone resorption will be induced in vivo using the pressurized bulla model. 3H-uridine incorporation into bone cells will be used as a measure of increased RNA transcription. A potential role of interleukin-1 in osteoclastic activity in vivo and in vitro will be investigated by attempting to block induced, localized bone resorption with the recently discovered interleukin-l receptor antagonist. The potential of the tissue-type, and urokinase-type plasminogen activators to affect osteoclastic resorption will be determined using the mouse calvarial organ culture.