0000000000065358
AUTHOR
Volker Lennerz
Analysis of nucleophosmin–anaplastic lymphoma kinase (NPM‐ALK)‐reactive CD8+ T cell responses in children with NPM‐ALK+ anaplastic large cell lymphoma
Summary Cellular immune responses against the oncoantigen anaplastic lymphoma kinase (ALK) in patients with ALK-positive anaplastic large cell lymphoma (ALCL) have been detected using peptide-based approaches in individuals preselected for human leucocyte antigen (HLA)-A*02:01. In this study, we aimed to evaluate nucleophosmin (NPM)-ALK-specific CD8+ T cell responses in ALCL patients ensuring endogenous peptide processing of ALK antigens and avoiding HLA preselection. We also examined the HLA class I restriction of ALK-specific CD8+ T cells. Autologous dendritic cells (DCs) transfected with in-vitro-transcribed RNA (IVT-RNA) encoding NPM–ALK were used as antigen-presenting cells for T cell …
Identification of NM23-H2 as a tumour-associated antigen in chronic myeloid leukaemia.
Therapeutic effects of haematopoietic stem cell transplantation are not limited to maximal chemoradiotherapy and subsequent bone marrow regeneration, but include specific as well as unspecific immune reactions known as graft-versus-leukaemia (GvL) effects. Specific immune reactions are likely to be particularly relevant to the long-term treatment of diseases, such as chronic myeloid leukaemia (CML), in which residual cells may remain quiescent and unresponsive to cytotoxic and molecular therapies for long periods of time. Specific GvL effects result from the expression on leukaemic cells of specific tumour-associated antigens (TAAs) in the context of HLA proteins. As human leukocyte antigen…
Abstract 5516: Therapeutic vaccination with the survivin-derived multi-epitope vaccine EMD640744 in patients with advanced solid tumors
Abstract Background: Survivin is a promising tumor-associated antigen for cancer immunotherapy that fulfills two major criteria for this purpose: (1) tumor cells depend on the actions of survivin (inhibition of apoptosis, unrestricted proliferation and angiogenesis); and (2) the protein has demonstrated immunogenicity in patients with different cancers. Here we report results of a first-in-man Phase I study with EMD640744, a cocktail of survivin-derived partially modified HLA class I-restricted peptides in Montanide® ISA 51 VG. Methods: This multicenter, open-label, parallel group, randomized study compared the immunologic efficacy, safety, tolerability and clinical activity of three dosage…
Exome Sequencing to Predict Neoantigens in Melanoma
Abstract The ability to use circulating peripheral blood cells and matched tumor sequencing data as a basis for neoantigen prediction has exciting possibilities for application in the personalized treatment of cancer patients. We have used a high-throughput screening approach, combining whole-exome sequence data, mRNA microarrays, and publicly available epitope prediction algorithm output to identify mutated proteins processed and displayed by patient tumors and recognized by circulating immune cells. Matched autologous melanoma cell lines and peripheral blood mononuclear cells were used to create mixed lymphocyte tumor cell cultures, resulting in an expansion of tumor-reactive T cells to u…
Evolution of melanoma cross-resistance to CD8⁺ T cells and MAPK inhibition in the course of BRAFi treatment
The profound but frequently transient clinical responses to BRAFV600 inhibitor (BRAFi) treatment in melanoma emphasize the need for combinatorial therapies. Multiple clinical trials combining BRAFi and immunotherapy are under way to further enhance therapeutic responses. However, to which extent BRAFV600 inhibition may affect melanoma immunogenicity over time remains largely unknown. To support the development of an optimal treatment protocol, we studied the impact of prolonged BRAFi exposure on the recognition of melanoma cells by T cells in different patient models. We demonstrate that autologous CD8+ tumor-infiltrating lymphocytes (TILs) efficiently recognized short-term (3, 7 days) BRAF…
CD8+ cytotoxic T lymphocytes isolated from allogeneic healthy donors recognize HLA class Ia/Ib–associated renal carcinoma antigens with ubiquitous or restricted tissue expression
AbstractAllogeneic hematopoietic stem cell transplantation can induce considerable tumor remissions in metastatic renal-cell carcinoma (RCC) patients. The precise effector mechanisms mediating these graft-versus-tumor reactions are unknown. We studied RCC-directed CD8+ T-cell responses in blood lymphocytes of healthy individuals matched with established RCC cell lines for HLA-class I. In 21 of 22 allogeneic mixed lymphocyte/tumor-cell cultures (MLTCs), RCC-reactive cytotoxic T-lymphocytes (CTLs) were readily obtained. From MLTCs, 121 CD8+ CTL clones with memory phenotype were isolated. Their anti–RCC reactivity was restricted by multiple classical HLA-Ia molecules, in particular by HLA-A2, …
Genetic evolution of T-cell resistance in the course of melanoma progression
Abstract Purpose: CD8+ T lymphocytes can kill autologous melanoma cells, but their activity is impaired when poorly immunogenic tumor phenotypes evolve in the course of disease progression. Here, we analyzed three consecutive melanoma lesions obtained within one year of developing stage IV disease for their recognition by autologous T cells. Experimental Design: One skin (Ma-Mel-48a) and two lymph node (Ma-Mel-48b, Ma-Mel-48c) metastases were analyzed for T-cell infiltration. Melanoma cell lines established from the respective lesions were characterized, determining the T-cell–stimulatory capacity, expression of surface molecules involved in T-cell activation, and specific genetic alteratio…
Melanomas resist T-cell therapy through inflammation-induced reversible dedifferentiation.
Adoptive cell transfer therapies (ACTs) with cytotoxic T cells that target melanocytic antigens can achieve remissions in patients with metastatic melanomas, but tumours frequently relapse. Hypotheses explaining the acquired resistance to ACTs include the selection of antigen-deficient tumour cell variants and the induction of T-cell tolerance. However, the lack of appropriate experimental melanoma models has so far impeded clear insights into the underlying mechanisms. Here we establish an effective ACT protocol in a genetically engineered mouse melanoma model that recapitulates tumour regression, remission and relapse as seen in patients. We report the unexpected observation that melanoma…
Melanoma Lesions Independently Acquire T-cell Resistance during Metastatic Latency
Abstract Melanoma often recurs after a latency period of several years, presenting a T cell–edited phenotype that reflects a role for CD8+ T cells in maintaining metastatic latency. Here, we report an investigation of a patient with multiple recurrent lesions, where poorly immunogenic melanoma phenotypes were found to evolve in the presence of autologous tumor antigen–specific CD8+ T cells. Melanoma cells from two of three late recurrent metastases, developing within a 6-year latency period, lacked HLA class I expression. CD8+ T cell–resistant, HLA class I–negative tumor cells became clinically apparent 1.5 and 6 years into stage IV disease. Genome profiling by SNP arrays revealed that HLA …
Allorestricted T lymphocytes with a high avidity T-cell receptor towards NY-ESO-1 have potent anti-tumor activity.
The cancer-testis antigen NY-ESO-1 has been targeted as a tumor-associated antigen by immunotherapeutical strategies, such as cancer vaccines. The prerequisite for a T-cell-based therapy is the induction of T cells capable of recognizing the NY-ESO-1-expressing tumor cells. In this study, we generated human T lymphocytes directed against the immunodominant NY-ESO-1(157-165) epitope known to be naturally presented with HLA-A*0201. We succeeded to isolate autorestricted and allorestricted T lymphocytes with low, intermediate or high avidity TCRs against the NY-ESO-1 peptide. The avidity of the established CTL populations correlated with their capacity of lysing HLA-A2-positive, NY-ESO-1-expre…
7 Evolution of cross-resistance to CD8+ T cells in the course of BRAF and MEK inhibitor treatment in BRAFV600E melanoma
Introduction The BRAFV600 mutation, expressed in approximately 50% of melanomas, mediates constitutive activation of the BRAF-MEK-ERK in the MAPK signalling pathway and therefore tumour proliferation. Rapid and high rate of clinical responses can be achieved by targeting this axis using BRAF V600 inhibitor (BRAFi) as single therapy or the combination of BRAFi and MEKi (BRAFi/MEKi). But still disease progresses in the majority of treated patients due to acquired resistance in tumour cells. Combining targeted therapy with immunotherapy is proposed to improve the long-term outcomes of patients. However, to which extent BRAFi may affect melanoma immunogenicity over time remains largely unknown.…
The response of autologous T cells to a human melanoma is dominated by mutated neoantigens
Our understanding of pathways leading to antitumor immunity may depend on an undistorted knowledge of the primary antigenic targets of patients' autologous T cell responses. In the melanoma model derived from patient DT, we applied cryopreserved short-term autologous mixed lymphocyte–tumor cell cultures (MLTCs) in combination with an IFN-γ enzyme-linked immunospot (ELISPOT) assay to cDNA expression screening. We identified three previously unknown peptides processed from melanosomal proteins tyrosinase (presented by HLA-A*2601 and -B*3801) and gp100 (presented by HLA-B*07021) and five neoantigens generated by somatic point mutations in the patient's melanoma. The mutations were found in the…
Temozolomide- and fotemustine-induced apoptosis in human malignant melanoma cells: response related to MGMT, MMR, DSBs, and p53
Malignant melanomas are highly resistant to chemotherapy. First-line chemotherapeutics used in melanoma therapy are the methylating agents dacarbazine (DTIC) and temozolomide (TMZ) and the chloroethylating agents BCNU and fotemustine. Here, we determined the mode of cell death in 11 melanoma cell lines upon exposure to TMZ and fotemustine. We show for the first time that TMZ induces apoptosis in melanoma cells, using therapeutic doses. For both TMZ and fotemustine apoptosis is the dominant mode of cell death. The contribution of necrosis to total cell death varied between 10 and 40%. The O(6)-methylguanine-DNA methyltransferase (MGMT) activity in the cell lines was between 0 and 1100 fmol m…
Short Peptide Vaccine Induces CD4+ T Helper Cells in Patients with Different Solid Cancers.
Abstract Previous cancer vaccination trials often aimed to activate CD8+ cytotoxic T-cell (CTL) responses with short (8–10mer) peptides and targeted CD4+ helper T cells (TH) with HLA class II–binding longer peptides (12–16 mer) that were derived from tumor antigens. Accordingly, a study of immunomonitoring focused on the detection of CTL responses to the short, and TH responses to the long, peptides. The possible induction of concurrent TH responses to short peptides was widely neglected. In a recent phase I vaccination trial, 53 patients with different solid cancers were vaccinated with EMD640744, a cocktail of five survivin-derived short (9- or 10-mer) peptides in Montanide ISA 51VG. We m…
Characterization of Renal-Cell Carcinoma (RCC)-Reactive Cytotoxic T-Lymphocyte Responses Generated from Peripheral Blood of HLA-Matched Sibling and Unrelated Healthy Individuals in Vitro.
Abstract Although current allo-transplantation therapy can induce considerable graft-versus-tumor (GvT) effects in RCC patients, it is also accompanied by severe, even life-threatening side effects, mainly due to graft-versus-host disease (GvHD). Efforts aiming to improve the specificity and efficiency of allogeneic cell therapy in this disease (e.g. specific donor lymphocyte infusion or vaccination) will certainly benefit from the identification of potential anti-tumor effector mechanisms and their corresponding target structures. We recently demonstrated that RCC-reactive cytotoxic T-lymphocyte (CTL) clones can be isolated from peripheral blood of healthy donors matched with the RCC stimu…
Superior antitumor in vitro responses of allogeneic matched sibling compared with autologous patient CD8+ T cells.
AbstractAllogeneic cell therapy as a means to break immunotolerance to solid tumors is increasingly used for cancer treatment. To investigate cellular alloimmune responses in a human tumor model, primary cultures were established from renal cell carcinoma (RCC) tissues of 56 patients. In three patients with stable RCC line and human leukocyte antigen (HLA)-identical sibling donor available, allogeneic and autologous RCC reactivities were compared using mixed lymphocyte/tumor cell cultures (MLTC). Responding lymphocytes were exclusively CD8+ T cells, whereas CD4+ T cells or natural killer cells were never observed. Sibling MLTC populations showed higher proliferative and cytolytic antitumor …
Generation of CD8+T cells expressing two additional T-cell receptors (TETARs) for personalised melanoma therapy
Adoptive T-cell therapy of cancer often fails due to the tumor cells' immune escape mechanisms, like antigen loss or down-regulation. To anticipate immune escape by loss of a single antigen, it would be advantageous to equip T cells with multiple specificities. To study the possible interference of 2 T-cell receptors (TCRs) in one cell, and to examine how to counteract competing effects, we generated TETARs, CD8(+) T cells expressing two additional T-cell receptors by simultaneous transient transfection with 2 TCRs using RNA electroporation. The TETARs were equipped with one TCR specific for the common melanoma antigen gp100 and one TCR recognizing a patient-specific, individual mutation of…
NPM-ALK-reactive T-cell responses in children and adolescents with NPM-ALK positive anaplastic large cell lymphoma
ABSTRACT The oncoantigen nucleophosmin-anaplastic lymphoma kinase (NPM-ALK) induces cellular and humoral immune responses in patients with NPM-ALK-positive anaplastic large cell lymphoma (ALCL). We characterize the NPM-ALK-specific T-cell responses in a cohort of pediatric and adolescent ALCL-patients in remission without Human Leucocyte Antigen (HLA)-preselection. First, we assessed NPM-ALK-reactive T-cell responses and their HLA-class I restriction in patients by using dendritic cells (DCs) transfected with in vitro transcribed (IVT) NPM-ALK-RNA for CD8 (n = 20) or CD3 (n = 9) T-cell stimulation. NPM-ALK-specific T-cells were detected in twelve of 29 patients (nine of 20 with CD8-selected…
Rapid molecular dissection of viral and bacterial immunomes
The development of preventive or therapeutic recombinant vaccines and the generation of serodiagnostic assays for infectious diseases depend essentially on the availability of molecularly defined antigens. A major bottleneck for the identification of suitable target antigens for many pathogens is the isolation of sufficient amounts of material for subsequent genomic or proteomic screening. Applying a highly efficient expression cloning strategy to the human pathogens vaccinia virus (VV) and Chlamydia pneumoniae (CP), we demonstrate that sub-nanogram amounts of isolated nucleic acids can be utilized to determine comprehensive sets of immunodominant antigens. Remarkably, the approach not only…
186: Superior antitumor in vitro responses of allogeneic matched sibling compared to autologous patient CD8+ T cells
Allogeneic cell therapy as a means to break immunotolerance to solid tumors is increasingly used for cancer treatment. To investigate cellular alloimmune responses in a human tumor model, primary cultures were established from renal cell carcinoma (RCC) tissues of 56patients. In three patients with stable RCC line and human leukocyte antigen (HLA)-identical sibling donor available, allogeneic and autologous RCC reactivities were compared using mixed lymphocyte/ tumor cell cultures (MLTC). Responding lymphocytes were exclusively CD8 + T cells, whereas CD4 + T cells or natural killer cells were never observed. Sibling MLTC populations showed higher proliferative and cytolytic antitumor respon…