Strategy for monitoring T cell responses to NY-ESO-1 in patients with any HLA class I allele

Abstract

NY-ESO-1 elicits frequent antibody responses in cancer patientsN Y-ESO-1 is a member of the cancer͞testis family of genes (1). Expression of NY-ESO-1 in normal tissues is limited to germ cells, but in cancer, NY-ESO-1 is expressed in a broad range of different tumor types. NY-ESO-1 was discovered by serological analysis of a recombinant cDNA expression library obtained from an esophageal cancer (1). NY-ESO-1 is one of the most immunogenic tumor antigens defined to date, eliciting a humoral response in nearly half of patients with advanced cancers expressing NY-ESO-1 (2) along with a strong CD8 ϩ T cell (3-6) and CD4 ϩ T cell (7) response. Using optimized techniques for analyzing antibodies and newer methodologies for CD8 ϩ T cell responses, such as HLAA2͞peptide tetramer complexes and enzyme-linked immunospot (Elispot) assays, we recently obtained a comprehensive picture of the spontaneous immune response against NY-ESO-1 in a cohort of patients with advanced tumors (4). The study showed that humoral and cellular responses occurred simultaneously against NY-ESO-1. Antibodies appeared to be good indicators of CD8 ϩ T cell responses in this system. Studies of T cell reactivity against NY-ESO-1, however, remain limited because of the few epitopes described thus far. With regard to HLA-A2-restricted epitopes, three overlapping NY-ESO-1 peptides are known (3). Wang et al. (8) defined epitopes presented by the HLA-A31 molecule, encoded by both the normal and an alternative reading frame of NY-ESO-1.In the present study, we devised an assay to monitor CD8 ϩ T lymphocyte responses to NY-ESO-1 in cancer patients that does not require knowledge of predefined peptide epitopes or particular HLA profiles. Recombinant adenovirus and vaccinia vectors were constructed to express the full-length NY-ESO-1 gene. The first vector was used to transduce antigen-presenting cells (APCs) with NY-ESO-1 and stimulate memory effector T cells from cancer patients, and the second was used to induce antigen expression in B cells, the targets for measuring T cell responses. Using this set of non-cross-reactive recombinant viruses, we recalled and characterized CD8 ϩ T cell responses against naturally processed NY-ESO-1 epitopes. Materials and MethodsTumor Typing for NY-ESO-1 mRNA. Expression of NY-ESO-1 mRNA in tumor specimens was assessed by reverse transcription-PCR, using previously described primers (1).Assays for NY-ESO-1 Antibody. NY-ESO-1 serum antibodies were assayed by ELISA and Western blots, using NY-ESO-1 recombinant protein purified from Escherichia coli (2).Generation of Viral Vectors. Adenoviral constructs Ad2͞EV (empty vector) and Ad2͞EGFP (encoding green fluorescent protein) have been described previously (9). Adenovirus recombinant for NY-ESO-1 (Ad2͞ESO) was generated with a cloning method described previously (10). Briefly, pBK-CMV NY-ESO-1 (1) was digested with EcoRI and XbaI, and an 0.8-kb NY-ESO-1 fragment was isolated and cloned into EcoRI and XbaI sites of pSV2-ICEU-1 pAd Quick shuttle vector. The shuttle plasmid pSV2-...

Recombinant vaccinia/fowlpox NY-ESO-1 vaccines induce both humoral and cellular NY-ESO-1-specific immune responses in cancer patients

“…Recombinant rV-NY-ESO-1 and rF-NY-ESO-1 constructs were obtained from Therion Biologics Corporation (Cambridge, MA) (26).…”

Intravenous Injection of a Lentiviral Vector Encoding NY-ESO-1 Induces an Effective CTL Response

“…NY-ESO-1 elicits a combined Ab and T cell response (28). Several epitopes of NY-ESO-1 presented by HLA class II molecules (29 -32) and HLA class I molecules (28,33,34) have been identified. Previous work from our group has shown that priming of HLA-A2 (A2) transgenic mice with plasmid DNA and recombinant vaccinia virus encoding the A2-restricted epitope NY-ESO-1 157-165 elicits a strong NY-ESO-1 157-165 -specific CTL response (35).…”

Cancer/testis antigen CT45: Analysis of mRNA and protein expression in human cancer

“…This combination of restricted normal tissue expression, spontaneous immunogenicity and frequent tumor expression has pushed MAGE and NY-ESO-1 to the forefront of tumor immunotherapy as attractive targets for cancer vaccines, 1,8 and multiple clinical trials using these 2 antigens have been carried out, with promising results observed in some studies. [9][10][11][12][13][14][15][16][17] Following the initial identification of MAGE and NY-ESO-1 families, more than 80 gene or gene families have been described as CT or CT candidate genes in the literature. These genes have been organized and annotated into a CT database by the Ludwig Institute for Cancer Research (http://www.cancerimmunity.org/ Ctdatabase/ and http://www.cta.lncc.br).…”