Tumor regression in patients with metastatic synovial cell sarcoma and melanoma using genetically engineered lymphocytes reactive with NY-ESO-1.

PURPOSE: Adoptive immunotherapy using tumor-infiltrating lymphocytes represents an effective cancer treatment for patients with metastatic melanoma. The NY-ESO-1 cancer/testis antigen, which is expressed in 80% of patients with synovial cell sarcoma and approximately 25% of patients with melanoma and common epithelial tumors, represents an attractive target for immune-based therapies. The current trial was carried out to evaluate the ability of adoptively transferred autologous T cells transduced with a T-cell receptor (TCR) directed against NY-ESO-1 to mediate tumor regression in patients with metastatic melanoma and synovial cell sarcoma. PATIENTS AND METHODS: A clinical trial was performed in patients with metastatic melanoma or metastatic synovial cell sarcoma refractory to all standard treatments. Patients with NY-ESO-1-positive tumors were treated with autologous TCR-transduced T cells plus 720,000 iU/kg of interleukin-2 to tolerance after preparative chemotherapy. Objective clinical responses were evaluated using Response Evaluation Criteria in Solid Tumors (RECIST). RESULTS: Objective clinical responses were observed in four of six patients with synovial cell sarcoma and five of 11 patients with melanoma bearing tumors expressing NY-ESO-1. Two of 11 patients with melanoma demonstrated complete regressions that persisted after 1 year. A partial response lasting 18 months was observed in one patient with synovial cell sarcoma. CONCLUSION: These observations indicate that TCR-based gene therapies directed against NY-ESO-1 represent a new and effective therapeutic approach for patients with melanoma and synovial cell sarcoma. To our knowledge, this represents the first demonstration of the successful treatment of a nonmelanoma tumor using TCR-transduced T cells.

Different adjuvanticity of incomplete freund's adjuvant derived from beef or vegetable components in melanoma patients immunized with a peptide vaccine.

Adjuvants are requisite components of many vaccines designed to elicit T-cell immunity although the exact components of commonly used adjuvants are not always fully defined. In 2006, owing to concerns of prion contamination, the formulation of Montanide ISA 51 Incomplete Freund's Adjuvant (IFA) was changed from using oleic acid isolated from beef tallow to that isolated from olives. In sequential clinical trials in the Surgery Branch, NCI patients at high risk for recurrence of melanoma were immunized with the gp100 melanoma/melanocyte antigenic peptide, gp100: 209-217 (210M), emulsified in the beef-derived IFA or the olive-derived IFA. The in vivo generation of gp100 reactive T cells was significantly less in patients receiving the olive compared with the beef IFA as assessed by both ELISPOT (P2=0.0001) and in vitro sensitization assays (P2=0.0001). Local skin reactions to the peptide emulsion were also far less severe using the olive IFA (P2=0.0003). Thus it seems likely that contaminants in the beef-derived IFA played an important role in the increased adjuvanticity of this preparation compared with the olive-derived IFA. These findings raise serious concerns related to the use of the available olive-derived IFA for immunization in clinical trials. A survey of ongoing clinical trials listed in ClinicalTrials.gov revealed 36 trials currently accruing patients that are using the olive-derived Montanide ISA 51 IFA.

Gene therapy with human and mouse T-cell receptors mediates cancer regression and targets normal tissues expressing cognate antigen.

Gene therapy of human cancer using genetically engineered lymphocytes is dependent on the identification of highly reactive T-cell receptors (TCRs) with antitumor activity. We immunized transgenic mice and also conducted high-throughput screening of human lymphocytes to generate TCRs highly reactive to melanoma/melanocyte antigens. Genes encoding these TCRs were engineered into retroviral vectors and used to transduce autologous peripheral lymphocytes administered to 36 patients with metastatic melanoma. Transduced patient lymphocytes were CD45RA(-) and CD45RO(+) after ex vivo expansion. After infusion, the persisting cells displayed a CD45RA(+) and CD45RO(-) phenotype. Gene-engineered cells persisted at high levels in the blood of all patients 1 month after treatment, responding patients with higher ex vivo antitumor reactivity than nonresponders. Objective cancer regressions were seen in 30% and 19% of patients who received the human or mouse TCR, respectively. However, patients exhibited destruction of normal melanocytes in the skin, eye, and ear, and sometimes required local steroid administration to treat uveitis and hearing loss. Thus, T cells expressing highly reactive TCRs mediate cancer regression in humans and target rare cognate-antigen-containing cells throughout the body, a finding with important implications for the gene therapy of cancer. This trial was registered at www.ClinicalTrials.gov as NCI-07-C-0174 and NCI-07-C-0175.

IL-7 administration to humans leads to expansion of CD8+ and CD4+ cells but a relative decrease of CD4+ T-regulatory cells.

Lymphopenia is a serious consequence of HIV infection and the administration of cancer chemotherapeutic agents. Although growth factors can be administered to patients to increase circulating neutrophils, there is no effective method to stimulate CD8+ lymphocyte production in humans, in vivo. This report is the first to describe the administration of recombinant interleukin-7 to humans and demonstrates the ability of this cytokine to mediate selective increases in CD4+ and CD8+ lymphocytes along with a decrease in the percentage of CD4+ T-regulatory cells. These studies suggest an important role for interleukin-7 in the treatment of patients with lymphopenia.

Altered CD8(+) T-cell responses when immunizing with multiepitope peptide vaccines.

Efforts to develop effective cancer vaccines often use combinations of immunogenic peptides to increase the applicability and effectiveness of the immunizations. The immunologic consequences of combining more than 1 self/tumor antigen in a single vaccine emulsion remain unclear, however. We performed 2 sequential clinical trials in patients at high risk for melanoma recurrence. Patients were given the highly immunogenic gp100:209-217(210M) peptide and the less immunogenic tyrosinase:368-376(370D) peptide once every 3 weeks for 4 weeks. This vaccination course was 12 weeks long, and patients were vaccinated for up to 4 courses (16 total vaccinations). In the first trial in 31 patients, the peptides were emulsified separately in incomplete Freund adjuvant and injected at 2 different sites. In the second trial in 33 patients, the peptides were emulsified together and injected at the same site. Cryopreserved lymphocytes were obtained by apheresis after each course and were evaluated for antipeptide activity using tetramer, enzyme-linked immunospot, and in vitro sensitization boost assays. When the peptides were injected at separate sites, robust specific reactivity to the native gp100:209-217 peptide was measured by each of the assays, whereas immunization with the tyrosinase:368-376(370D) peptide was far less effective. When the peptides were emulsified and injected together at the same site, immunization to the gp100:209-217(210M) epitope dropped precipitously, whereas reactivity to the tyrosinase:368-376(370D) peptide was enhanced. These cautionary data indicate that mixing peptides in the same emulsion can alter reactivity compared with peptides injected separately by mechanisms that may include the induction of localized nonspecific inflammation or competitive binding of peptides to major histocompatibility complex molecules.

Tumor progression can occur despite the induction of very high levels of self/tumor antigen-specific CD8+ T cells in patients with melanoma.

The identification of many tumor-associated epitopes as nonmutated "self" Ags led to the hypothesis that the induction of large numbers of self/tumor Ag-specific T cells would be prevented because of central and peripheral tolerance. We report in this study on vaccination efforts in 95 HLA-A*0201 patients at high risk for recurrence of malignant melanoma who received prolonged immunization with the "anchor-modified" synthetic peptide, gp100209-217(210M). Vaccination using this altered peptide immunogen was highly effective at inducing large numbers of self/tumor-Ag reactive T cells in virtually every patient tested, with levels as high as 42% of all CD8+ T cells assessed by tetramer analysis. From 1 to 10% of all CD8+ cells were tumor-Ag reactive in 44% of patients and levels >10% were generated in 17% of patients. These studies were substantiated using the ELISPOT assay and a bulk cytokine release assay. Although our data regarding "tumor escape" were inconclusive, some patients had growing tumors that expressed Ag and HLA-A*0201 in the presence of high levels of antitumor T cells. There was no difference in the levels of antitumor Ag-specific T cells in patients who recurred compared with those that remained disease-free. Thus, the mere presence of profoundly expanded numbers of vaccine-induced, self/tumor Ag-specific T cells cannot by themselves be used as a "surrogate marker" for vaccine efficacy. Further, the induction of even high levels of antitumor T cells may be insufficient to alter tumor progression.