RECOMBINANT VACCINES FOR ACTIVE SPECIFIC IMMUNOTHERAPY OF HUMAN CARCINOMA

某些肿瘤相关抗原（TAA）是潜在的靶点 主动特异性免疫疗法目前正在进行研究， 免疫原性、安全性和毒性 重组牛痘病毒 表达人肿瘤相关抗原，作为免疫原， 治疗人类癌症。我们已经构建了，特征化， 测定了两种重组痘苗病毒的安全性和免疫原性 病毒在小鼠肿瘤模型以及恒河猴中的作用。的 第一个重组牛痘病毒含有人类 癌胚抗原，并被指定为rV-CEA;和第二 牛痘病毒，命名为rV-PSA，表达人前列腺特异性 抗原的CEA是一种18 OKd糖蛋白，在人乳腺癌组织中高表达， 结肠直肠癌、胃癌、胰腺癌、乳腺癌和非小细胞癌， 而PSA是前列腺中过表达的30-33 Kd糖蛋白 carcinoma.目前还不清楚这些TAA在人体中是否具有免疫原性; 对这些肿瘤抗原的细胞介导的应答尚未被 在正常或癌症患者中记录。抗肿瘤活性 在动物肿瘤模型中，通过用rV-L1免疫小鼠证实了这一点。 CEA。 这种重组免疫原也显示出诱导细胞- 介导的和体液CEA特异性免疫应答， 非人类灵长类动物 其他免疫原，如多核苷酸疫苗 表达人CEA的细胞也显示出诱导抗肿瘤和CEA。 特异性细胞介导的小鼠免疫应答。 rV-CEA免疫原 已经在I期临床试验中进行了评估，其中几个 结果显示，患者可引发对CEA的特异性T细胞应答， 免疫后。rV-PSA的安全性也得到了评估 以及在小鼠和恒河猴中的免疫原性。Southern印迹 分析表明恒河猴体内含有 与人PSA高度相关，因此代表了用于 rV-PSA引发细胞免疫应答的能力。rV-PSA是 在这些动物模型中显示无毒性。 恒河猴 能够引发PSA特异性体液以及T细胞 用rV-PSA免疫后的淋巴增殖反应。 表达共刺激分子B7-1的重组痘苗病毒 和B7-2的构建、表征和分析， 增强小鼠中CEA特异性细胞免疫应答的能力 肿瘤模型 rV-B7-1能增强CEA特异性免疫反应， 当与rV-CEA共同施用时，肿瘤细胞感染 rV-B7-1增强了小鼠肿瘤的免疫原性， 免疫原性具有长期记忆。 肿瘤细胞的直接感染 与rV-B7-1和免疫患者与这些肿瘤细胞可能 开辟了一条免疫治疗的新途径。 用rV-1感染肿瘤细胞 B7可以比基因治疗更快，更有效地完成 使用逆转录病毒载体的协议，并似乎引出正确的 抗肿瘤反应。 增强rV-CEA和rV-PSA的其他方法 主要免疫后的特异性免疫原性 使用纯化的重组蛋白、肽和 多核苷酸疫苗。 重组牛痘病毒，其含有 c-erb/B2和乳腺粘蛋白muc-1基因也分别被 设计和建造。

Certain tumor associated antigens (TAAs) represent potential targets for active specific immunotherapy. Studies are ongoing to evaluate the immunogenicity, safety, and toxicity of recombinant vaccinia viruses expressing human tumor associated antigens, as immunogens for the treatment of human carcinomas. We have constructed, characterized and determined the safety and immunogenicity of two recombinant vaccinia viruses in both a murine tumor model as well as rhesus monkeys. The first recombinant vaccinia virus contained the gene for the human carcinoembryonic antigen and was designated rV-CEA; and the second vaccinia virus, designated rV-PSA, expressed human prostate specific antigen. CEA is a 18OKd glycoprotein which is overexpressed in human colorectal, gastric, pancreatic, breast and non small cell carcinoma, while PSA is a 30-33 Kd glycoprotein overexpressed in prostatic carcinoma. It is unclear whether these TAAs are immunogenic in humans; cell mediated responses to these tumor antigens have not been documented in normal or cancer patients. Anti-tumor activity was demonstrated in an animal tumor model by immunization of mice with rV- CEA. This recombinant immunogen was also shown to induce both cell- mediated and humoral CEA specific immune responses in both mice and non-human primates. Other immunogens such as a polynucliotide vaccine expressing human CEA were also shown to elicit antitumor and CEA specific cell mediated immune responses in mice. The rV-CEA immunogen has been evaluated in Phase I clinical trials, where several patients were shown to elicit specific T-cell responses to CEA following immunization. rV-PSA has also been evaluated for its safety and immunogenicity in both mice and rhesus monkeys. Southern blot analyses have demonstrated that the rhesus monkey contains genes highly related to human PSA and thus represents a relevant model for the ability of rV-PSA to elicit a cellular immune response. rV-PSA was shown to have no toxicity in these animal models. Rhesus monkeys were able to elicit PSA specific humoral as well a T-cell lymphoproliferative responses after immunization with rV-PSA. Recombinant vaccinia virus expressing the costimulatory molecules B7-1 and B7-2 were constructed, characterized, and analyzed for their ability to enhance CEA specific cellular immune responses in a murine tumor model. rV-B7-1 was shown to enhance CEA specific immune responses when co-administered with rV-CEA. Infection of tumor cells with rV-B7-1 enhanced the immunogenicity of tumors in mice and this immunogenicity had long term memory. Direct infection of tumor cells with rV-B7-1 and immunization of patients with these tumor cells may open a new route of immunotherapy. Infection of tumor cells with rV- B7 can be accomplished faster and more efficiently than gene therapy protocols using retroviral vectors and appears to elicit the correct antitumor responses. Other approaches to enhance rV-CEA and rV-PSA specific immunogenicity following primarily immunization are being developed using purified recombinant proteins, peptides, and polynucleotide vaccines. Recombinant vaccinia viruses containing the c-erb/B2 and breast mucin muc-1 genes, respectively, have also been designed and constructed.