BREAST EPITHELIAL ANTIGENS AS TARGETS FOR RIA

参与其中的两个项目的总体目标是发展 并测试基于单克隆抗体的乳腺癌治疗新策略 癌这个项目将探讨乳腺癌的分子和细胞生物学 上皮抗原（BEAs）及其表位结构， 用于放射免疫治疗（RIT）的乳腺肿瘤定位的靶点。 项目2旨在识别乳腺识别的人类B淋巴细胞 肿瘤在其人类宿主中，产生人类单克隆抗体， 这些细胞通过建立稳定的细胞系， 基因工程，并开发放射免疫治疗的新策略 通过将现有的MoAb人源化和片段化， 临床试验 该项目的具体目标是： 1.分离和表征乳腺粘蛋白的细胞相关形式， BA46，并使用收集的 我们已经开发的MoAbs。 2.分离并表征由人MoAb鉴定的抗体 在项目2中开发。区分细胞相关型和分泌型。 3.分离并测序这些人识别的cDNA， 用于确定表位结构的单克隆抗体是最好的靶点， 是的。 4.确定最佳的细胞相关酶的分子结构 通过表位作图靶向RIT，构建嵌合重组体 抗原和寡糖分析，并通过体外和体内 （项目2）临床前评价。 某些抗乳腺粘蛋白和46 kDa乳腺抗原（BA 46）的单克隆抗体 在RIT中有效。因为乳房的加工过程发生了改变 在串联重复结构域中的粘蛋白一些表位优先被 在乳腺癌中表达，因此某些MoAb识别这些 通常隐蔽表位在成像中比其他表位更有效 乳腺癌患者的转移。此外，对于BA46抗原，一些MoAb 在临床前的RIT研究中，这 可能与该抗原可能的自分泌/旁分泌功能有关， 参与细胞相互作用，和不同的表位结构域的 分子。在项目2中制备的人单克隆抗体可以鉴定 如果是这样，将确定精确的表位。 如果鉴定出新的抗原，它们将被分离和表征， 克隆并测序了它们的cDNA。将通过以下方法分析表位： 表位作图、寡糖分析和重组体的产生 抗原及其片段作为嵌合蛋白。分子 表位的特征将与治疗相关， 体外和体内（项目2）临床前研究的有效性， 为放射免疫治疗筛选最佳靶表位和单克隆抗体。

The overall goal of the two projects participating in this is to develop and test new monoclonal antibody based strategies for treatment of breast cancer. This project will explore the molecular and cell biology of breast epithelial antigens (BEAs) and their epitope structures that are the best targets for breast tumor localization for radioimmunotherapy (RlT). Project 2 aims to identify human B-lymphocytes recognized by the breast tumor in its human host, produce human monoclonal antibodies secreted by these cells by establishing stable cell lines producing them through genetic engineering, and to develop new strategies for radioimmunotherapy by humanization and fragmentation of existing MoAbs for translation into clinical trials. The SPECIFIC AIMS of this project are: 1. Isolate and characterize cell-associated forms of the breast mucin and BA46 and distinguish them from secreted forms using the collection of MoAbs that we have already developed. 2. Isolate and characterize the BEA identified by the human MoAbs developed in Project 2. Distinguish cell-associated and secreted forms. 3. Isolate and sequence the cDNAs for the BEA recognized by these human MoAbs for determining the epitope structures that are the best target for RIT. 4. Determine molecular structures of cell-associated BEA that are the best target for RIT, by epitope mapping, construction of chimeric recombinant antigens and oligosaccharide analysis, and by in vitro and in vivo (Project 2) preclinical evaluation. Certain MoAbs against the breast mucin and a 46 kDa breast antigen (BA46) are effective in RIT. Because of the altered processing of the breast mucin some epitopes In the tandem repeat domain are preferentially expressed in breast carcinomas, and thus certain MoAbs recognizing these normally cryptic epitopes are more effective than others in imaging metastases in breast cancer patients. Also, for BA46 antigen, some MoAbs against it are more effective than others in preclinical RIT studies. This may be related to this antigen's possible autocrine/paracrine function and involvement in cell interaction, and the different epitope domains of the molecule. The human MoAbs prepared in Project 2 may identify epitopes on these latter two antigens, If so, the precise epitopes will be determined. If new antigens are identified they will be isolated and characterized, and their cDNAs cloned and sequenced. The epitopes will be analyzed by epitope mapping, oligosaccharide analysis, and production of recombinant antigens and their fragments as chimeric proteins. Molecular characteristics of the epitopes will be correlated with therapeutic effectiveness in in vitro and in vivo (Project 2) preclinical studies, in order to select the best target epitope and MoAb for radioimmunotherapy.