Identification of a K-b-restricted CTL epitope of beta-galactosidase: Potential use in development of immunization protocols for ''self'' antigens
Identification of a K-b-restricted CTL epitope of beta-galactosidase: Potential use in development of immunization protocols for ''self'' antigens
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DOI：
10.1006/meth.1997.0461
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发表时间：
1997-06-01
期刊：
影响因子：
--
通讯作者：
Restifo, NP
中科院分区：
文献类型：
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作者：
Overwijk, WW;Surman, DR;Restifo, NP
最近使用模型肿瘤相关抗原（TAA）探索了重组和合成疫苗在癌症治疗中的应用，其中许多模型并没有模拟正常组织表达 TAA 的免疫学状态。一种潜在有用的 Ag 模型是 β-半乳糖苷酶 (beta-gal)。由于这种酶的活性很容易检测到，因此该基因已被插入大量重组病毒和肿瘤中，对癌症疫苗学家有用。此外，还开发了许多具有β-gal组织特异性表达的转基因小鼠群体，从而能够建立对“自身”Ags的耐受性模型。由于大多数这些小鼠具有 H-2(b) 背景，我们生成了能够识别 C57BL\6 来源的表达 β-gal 的肿瘤细胞的细胞毒性 T 淋巴细胞 (CTL)，并确定它们的限制元件是 K-b 分子。使用等位基因特异性表位预测生成一组候选肽，我们确定 K-b 限制序列是 DAPIYTNV，对应于完整 β-gal 分子的氨基酸 96-103。构建了重组痘苗病毒(rVV-pes beta-gal(96-103))，其编码前面有内质网插入信号序列的肽表位。被该rVV感染的肿瘤细胞被用于识别表位的原始CTL识别。此外，用编码全长β-gal分子的rVV免疫并用DAPIYTNV肽再刺激的小鼠的脾细胞特异性识别表达β-gal的肿瘤细胞。这种免疫原性 β-gal 序列的鉴定使得能够在恶性疾病动物模型中建立免疫策略模型，其中靶抗原是“自身”蛋白质。
The use of recombinant and synthetic vaccines in the treatment of cancer has recently been explored using model tumor associated antigens (TAA), many of which do not model the immunological state of affairs in which the TAA is expressed by normal tissues. One potentially useful model Ag is beta-galactosidase (beta-gal). Because the activity of this enzyme is so easily detectable, this gene has been inserted into a large number of recombinant viruses and tumors useful to the cancer vaccinologist. In addition, numerous transgenic mouse colonies that have tissue-specific expression of beta-gal have been developed, enabling the modeling of tolerance to ''self'' Ags. Since most of these mice have an H-2(b) background, we generated cytotoxic T lymphocytes (CTL) capable of recognizing beta-gal-expressing tumor cells of C57BL\6 origin and have determined that their restriction element is the K-b molecule. Using an allele-specific epitope forecast to generate a panel of candidate peptides, we have determined that the K-b-restricted sequence is DAPIYTNV and corresponds to amino acids 96-103 of the intact beta-gal molecule. A recombinant vaccinia virus (rVV- pes beta-gal(96-103)) was constructed that encoded the peptide epitope preceded by an endoplasmic reticulum insertion signal sequence. Tumor cells infected with this rVV were recognized by the original CTL that had been used to identify the epitope. Furthermore, splenocytes of mice immunized with a rVV encoding the full-length beta-gal molecule and restimulated with the DAPIYTNV peptide specifically recognized tumor cells expressing beta-gal. The identification of this immunogenic beta-gal sequence enables the modeling of immunization strategies in animal models of malignant disease in which the target antigen is a ''self'' protein.