Krueger P, Nitz C, Moore J, Foster R, Gelber O, Gelber C
Molecular Discoveries, LLC, New York, New York 10017, USA.
J Immunother. 2001 Jul-Aug;24(4):334-44. doi: 10.1097/00002371-200107000-00009.
Employing a technology called differential immunization for antigen and antibody discovery (DIAAD), we aimed to generate monoclonal antibodies (mAbs) specific to human multiple myeloma (MM) cells. The fundamental principles of DIAAD rely on the induction of high zone tolerance to the "wild type" (normal) antigen. followed by immunization with the modified (diseased) antigen. Because chronic myelogenic leukemia (CML) cells are derived from a lineage closely related to MM, we immunized mice by contrasting a pool of MM cells with CML cells. Monoclonal antibody VAC69 reacted exclusively with MM cells, identifying a membrane molecule composed of a single-chain glycoprotein with a molecular weight of 78-120 kd. This antigen exhibited narrow tissue specificity and was not found on human cancers such as prostate, breast, or cervical carcinoma; leukemia; or lymphoma, nor was it seen on normal human peripheral lymphocytes or on Epstein-Barr virus-transformed B-cell lines. By immunohistochemistry, mAb VAC69 showed no binding to antigens expressed on normal human ovary, breast, prostate, lung or colon tissue, nor did it bind to human breast or prostate cancer. Conversely, mAb VAC69 bound strongly to human MM, although showing only slight binding to histiocytes or inflamed cells in human lymph nodes and human tumors of the colon, lung, and ovary. Monoclonal antibody VAC69 also triggered cancer-specific cytotoxicity in vitro (in the presence of complement) as well as in vivo using a sever combined immunodeficiency model transplanted with human MM. Further studies showed the ability of mAb VAC69 to be specifically internalized by human MM cells, indicating its potential use for therapeutic intervention in MM by delivering drugs into cancer cells.
我们采用一种名为抗原和抗体发现差异免疫法（DIAAD）的技术，旨在生成针对人类多发性骨髓瘤（MM）细胞的单克隆抗体（mAb）。DIAAD的基本原理依赖于对“野生型”（正常）抗原诱导高区耐受性，随后用修饰的（患病的）抗原进行免疫。由于慢性粒细胞白血病（CML）细胞来源于与MM密切相关的谱系，我们通过将MM细胞池与CML细胞进行对比来免疫小鼠。单克隆抗体VAC69仅与MM细胞发生反应，识别出一种由分子量为78 - 120 kd的单链糖蛋白组成的膜分子。这种抗原表现出狭窄的组织特异性，在前列腺癌、乳腺癌或宫颈癌等人类癌症、白血病或淋巴瘤中未发现，在正常人外周淋巴细胞或爱泼斯坦 - 巴尔病毒转化的B细胞系中也未见到。通过免疫组织化学，mAb VAC69对正常人卵巢、乳腺、前列腺、肺或结肠组织中表达的抗原无结合，对人类乳腺癌或前列腺癌也无结合。相反，mAb VAC69与人类MM强烈结合，尽管在人类淋巴结以及结肠、肺和卵巢的人类肿瘤中的组织细胞或炎症细胞上仅表现出轻微结合。单克隆抗体VAC69在体外（存在补体时）以及在移植了人类MM的严重联合免疫缺陷模型体内也引发了癌症特异性细胞毒性。进一步研究表明，mAb VAC69能够被人类MM细胞特异性内化，表明其通过将药物递送至癌细胞用于MM治疗干预的潜在用途。
