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Neutrophils can efficiently trigger cytotoxicity toward tumor cells and other target cells upon engagement of the IgA receptor CD89. However, the cell-intrinsic factors that influence the induction of cell death upon exposure to neutrophil effector mechanisms in vivo remain largely unknown. To uncover genetic regulators that influence target cell sensitivity to IgA-induced neutrophil-mediated killing, we used a human CD89 (hCD89) transgenic mouse model in which IgA-mediated killing of Her2-positive CD47-deficient murine target cells is mediated by neutrophils. Using a genome-wide in vivo screening approach, we demonstrate that deletion of the gene encoding inositol-tetrakisphosphate 1 kinase (ITPK1) increases survival of target cells in anti-Her2 IgA-treated mice. Moreover, we show that this effect depends on neutrophil activity and on the ITPK1 kinase domain. Notably, ITPK1 deficiency did not measurably impact survival of IgA-opsonized target cells in in vitro systems, underscoring the importance of in vivo screening systems to uncover physiologically relevant regulators of neutrophil killing.
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CD4+ T cells can either enhance or inhibit tumour immunity. Although regulatory T cells have long been known to impede antitumour responses1-5, other CD4+ T cells have recently been implicated in inhibiting this response6,7. Yet, the nature and function of the latter remain unclear. Here, using vaccines containing MHC class I (MHC-I) neoantigens (neoAgs) and different doses of tumour-derived MHC-II neoAgs, we discovered that whereas the inclusion of vaccines with low doses of MHC-II-restricted peptides (LDVax) promoted tumour rejection, vaccines containing high doses of the same MHC-II neoAgs (HDVax) inhibited rejection. Characterization of the inhibitory cells induced by HDVax identified them as type 1 regulatory T (Tr1) cells expressing IL-10, granzyme B, perforin, CCL5 and LILRB4. Tumour-specific Tr1 cells suppressed tumour rejection induced by anti-PD1, LDVax or adoptively transferred tumour-specific effector T cells. Mechanistically, HDVax-induced Tr1 cells selectively killed MHC-II tumour antigen-presenting type 1 conventional dendritic cells (cDC1s), leading to low numbers of cDC1s in tumours. We then documented modalities to overcome this inhibition, specifically via anti-LILRB4 blockade, using a CD8-directed IL-2 mutein, or targeted loss of cDC2/monocytes. Collectively, these data show that cytotoxic Tr1 cells, which maintain peripheral tolerance, also inhibit antitumour responses and thereby function to impede immune control of cancer.
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Antígenos de Neoplasias , Linfocitos T CD4-Positivos , Citotoxicidad Inmunológica , Inmunoterapia , Neoplasias , Linfocitos T Reguladores , Animales , Femenino , Humanos , Masculino , Ratones , Antígenos de Neoplasias/inmunología , Vacunas contra el Cáncer/inmunología , Vacunas contra el Cáncer/uso terapéutico , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Línea Celular Tumoral , Quimiocina CCL5/metabolismo , Células Dendríticas/inmunología , Granzimas/metabolismo , Antígenos de Histocompatibilidad Clase I/inmunología , Antígenos de Histocompatibilidad Clase II/inmunología , Interleucina-10/metabolismo , Interleucina-10/inmunología , Ratones Endogámicos C57BL , Neoplasias/inmunología , Neoplasias/terapia , Linfocitos T Reguladores/inmunología , Receptores Inmunológicos/antagonistas & inhibidores , Glicoproteínas de Membrana/antagonistas & inhibidores , Tolerancia Inmunológica , Linfocitos T CD8-positivos/inmunologíaRESUMEN
The sensitivity of malignant tissues to T cell-based immunotherapies depends on the presence of targetable human leukocyte antigen (HLA) class I ligands. Peptide-intrinsic factors, such as HLA class I affinity and proteasomal processing, have been established as determinants of HLA ligand presentation. However, the role of gene and protein sequence features as determinants of epitope presentation has not been systematically evaluated. We perform HLA ligandome mass spectrometry to evaluate the contribution of 7,135 gene and protein sequence features to HLA sampling. This analysis reveals that a number of predicted modifiers of mRNA and protein abundance and turnover, including predicted mRNA methylation and protein ubiquitination sites, inform on the presence of HLA ligands. Importantly, integration of such "hard-coded" sequence features into a machine learning approach augments HLA ligand predictions to a comparable degree as experimental measures of gene expression. Our study highlights the value of gene and protein features for HLA ligand predictions.
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Antígenos de Histocompatibilidad Clase I , Humanos , Ligandos , Antígenos de Histocompatibilidad Clase I/metabolismo , Antígenos de Histocompatibilidad Clase I/genética , ARN Mensajero/metabolismo , ARN Mensajero/genética , Secuencia de Aminoácidos , Aprendizaje Automático , Péptidos/metabolismo , Péptidos/químicaRESUMEN
BACKGROUND: Mismatch repair-deficient (dMMR) tumors can be found in 10 to 15% of patients with nonmetastatic colon cancer. In these patients, the efficacy of chemotherapy is limited. The use of neoadjuvant immunotherapy has shown promising results, but data from studies of this approach are limited. METHODS: We conducted a phase 2 study in which patients with nonmetastatic, locally advanced, previously untreated dMMR colon cancer were treated with neoadjuvant nivolumab plus ipilimumab. The two primary end points were safety, defined by timely surgery (i.e., ≤2-week delay of planned surgery owing to treatment-related toxic events), and 3-year disease-free survival. Secondary end points included pathological response and results of genomic analyses. RESULTS: Of 115 enrolled patients, 113 (98%; 97.5% confidence interval [CI], 93 to 100) underwent timely surgery; 2 patients had surgery delayed by more than 2 weeks. Grade 3 or 4 immune-related adverse events occurred in 5 patients (4%), and none of the patients discontinued treatment because of adverse events. Among the 111 patients included in the efficacy analysis, a pathological response was observed in 109 (98%; 95% CI, 94 to 100), including 105 (95%) with a major pathological response (defined as ≤10% residual viable tumor) and 75 (68%) with a pathological complete response (0% residual viable tumor). With a median follow-up of 26 months (range, 9 to 65), no patients have had recurrence of disease. CONCLUSIONS: In patients with locally advanced dMMR colon cancer, neoadjuvant nivolumab plus ipilimumab had an acceptable safety profile and led to a pathological response in a high proportion of patients. (Funded by Bristol Myers Squibb; NICHE-2 ClinicalTrials.gov number, NCT03026140.).
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Antineoplásicos Inmunológicos , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias del Colon , Reparación de la Incompatibilidad de ADN , Ipilimumab , Terapia Neoadyuvante , Nivolumab , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/genética , Neoplasias del Colon/patología , Neoplasias del Colon/cirugía , Supervivencia sin Enfermedad , Ipilimumab/administración & dosificación , Ipilimumab/efectos adversos , Ipilimumab/uso terapéutico , Nivolumab/administración & dosificación , Nivolumab/efectos adversos , Nivolumab/uso terapéutico , Tiempo de Tratamiento , Antineoplásicos Inmunológicos/administración & dosificación , Antineoplásicos Inmunológicos/efectos adversos , Antineoplásicos Inmunológicos/uso terapéutico , Países Bajos , Adulto JovenRESUMEN
In response to excessive DNA damage, human cells can activate p53 to induce apoptosis. Cells lacking p53 can still undergo apoptosis upon DNA damage, yet the responsible pathways are unknown. We observed that p53-independent apoptosis in response to DNA damage coincided with translation inhibition, which was characterized by ribosome stalling on rare leucine-encoding UUA codons and globally curtailed translation initiation. A genetic screen identified the transfer RNAse SLFN11 and the kinase GCN2 as factors required for UUA stalling and global translation inhibition, respectively. Stalled ribosomes activated a ribotoxic stress signal conveyed by the ribosome sensor ZAKα to the apoptosis machinery. These results provide an explanation for the frequent inactivation of SLFN11 in chemotherapy-unresponsive tumors and highlight ribosome stalling as a signaling event affecting cell fate in response to DNA damage.
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Apoptosis , Daño del ADN , Biosíntesis de Proteínas , Ribosomas , Proteína p53 Supresora de Tumor , Humanos , Línea Celular Tumoral , Codón/genética , Leucina/genética , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Ribosomas/metabolismo , Transducción de Señal , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/genética , Quinasas Quinasa Quinasa PAM/genética , Quinasas Quinasa Quinasa PAM/metabolismoRESUMEN
Tumor-specific CD8+ T cells are key effectors of antitumor immunity but are often rendered dysfunctional in the tumor microenvironment. Immune-checkpoint blockade can restore antitumor T-cell function in some patients; however, most do not respond to this therapy, often despite T-cell infiltration in their tumors. We here explored a CD8-targeted IL2 fusion molecule (CD8-IL2) to selectively reactivate intratumoral CD8+ T cells in patient-derived tumor fragments. Treatment with CD8-IL2 broadly armed intratumoral CD8+ T cells with enhanced effector capacity, thereby specifically enabling reinvigoration of the dysfunctional T-cell pool to elicit potent immune activity. Notably, the revival of dysfunctional T cells to mediate effector activity by CD8-IL2 depended on simultaneous antigen recognition and was quantitatively and qualitatively superior to that achieved by PD-1 blockade. Finally, CD8-IL2 was able to functionally reinvigorate T cells in tumors resistant to anti-PD-1, underscoring its potential as a novel treatment strategy for patients with cancer. Significance: Reinvigorating T cells is crucial for response to checkpoint blockade therapy. However, emerging evidence suggests that the PD-1/PD-L1 axis is not the sole impediment for activating T cells within tumors. Selectively targeting cytokines toward specific T-cell subsets might overcome these barriers and stimulate T cells within resistant tumors. See related article by Moynihan et al., p. 1206 (32).
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Linfocitos T CD8-positivos , Interleucina-2 , Neoplasias , Humanos , Linfocitos T CD8-positivos/inmunología , Neoplasias/inmunología , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Microambiente Tumoral/inmunología , Ratones , Animales , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Inhibidores de Puntos de Control Inmunológico/farmacología , Antígenos CD8/metabolismoRESUMEN
IL2 signals pleiotropically on diverse cell types, some of which contribute to therapeutic activity against tumors, whereas others drive undesired activity, such as immunosuppression or toxicity. We explored the theory that targeting of IL2 to CD8+ T cells, which are key antitumor effectors, could enhance its therapeutic index. To this aim, we developed AB248, a CD8 cis-targeted IL2 that demonstrates over 500-fold preference for CD8+ T cells over natural killer and regulatory T cells (Tregs), which may contribute to toxicity and immunosuppression, respectively. AB248 recapitulated IL2's effects on CD8+ T cells in vitro and induced selective expansion of CD8+T cells in primates. In mice, an AB248 surrogate demonstrated superior antitumor activity and enhanced tolerability as compared with an untargeted IL2Rßγ agonist. Efficacy was associated with the expansion and phenotypic enhancement of tumor-infiltrating CD8+ T cells, including the emergence of a "better effector" population. These data support the potential utility of AB248 in clinical settings. Significance: The full potential of IL2 therapy remains to be unlocked. We demonstrate that toxicity can be decoupled from antitumor activity in preclinical models by limiting IL2 signaling to CD8+ T cells, supporting the development of CD8+ T cell-selective IL2 for the treatment of cancer. See related article by Kaptein et al. p. 1226.
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Linfocitos T CD8-positivos , Interleucina-2 , Animales , Linfocitos T CD8-positivos/inmunología , Interleucina-2/farmacología , Ratones , Humanos , Línea Celular Tumoral , Ensayos Antitumor por Modelo de Xenoinjerto , Femenino , Neoplasias/inmunología , Neoplasias/tratamiento farmacológicoRESUMEN
T cell receptor (TCR) gene therapy is a potent form of cellular immunotherapy in which patient T cells are genetically engineered to express TCRs with defined tumor reactivity. However, the isolation of therapeutic TCRs is complicated by both the general scarcity of tumor-specific T cells among patient T cell repertoires and the patient-specific nature of T cell epitopes expressed on tumors. Here we describe a high-throughput, personalized TCR discovery pipeline that enables the assembly of complex synthetic TCR libraries in a one-pot reaction, followed by pooled expression in reporter T cells and functional genetic screening against patient-derived tumor or antigen-presenting cells. We applied the method to screen thousands of tumor-infiltrating lymphocyte (TIL)-derived TCRs from multiple patients and identified dozens of CD4+ and CD8+ T-cell-derived TCRs with potent tumor reactivity, including TCRs that recognized patient-specific neoantigens.
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Immunotherapy with immune-checkpoint inhibitors (ICIs) and targeted therapy with BRAF and MEK inhibitors have revolutionized the treatment of melanoma over the past decade. Despite these breakthroughs, the 5-year survival rate of patients with advanced-stage melanoma is at most 50%, emphasizing the need for additional therapeutic strategies. Adoptive cell therapy with tumour-infiltrating lymphocytes (TILs) is a therapeutic modality that has, in the past few years, demonstrated long-term clinical benefit in phase II/III trials involving patients with advanced-stage melanoma, including those with disease progression on ICIs and/or BRAF/MEK inhibitors. In this Review, we summarize the current status of TIL therapies for patients with advanced-stage melanoma, including potential upcoming marketing authorization, the characteristics of TIL therapy products, as well as future strategies that are expected to increase the efficacy of this promising cellular immunotherapy.
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Melanoma , Humanos , Melanoma/terapia , Inmunoterapia Adoptiva , Linfocitos Infiltrantes de Tumor , Proteínas Proto-Oncogénicas B-raf , Quinasas de Proteína Quinasa Activadas por MitógenosRESUMEN
Gastric and gastroesophageal junction (G/GEJ) cancers carry a poor prognosis, and despite recent advancements, most patients die of their disease. Although immune checkpoint blockade became part of the standard-of-care for patients with metastatic G/GEJ cancers, its efficacy and impact on the tumor microenvironment (TME) in early disease remain largely unknown. We hypothesized higher efficacy of neoadjuvant immunotherapy plus chemotherapy in patients with nonmetastatic G/GEJ cancer. In the phase 2 PANDA trial, patients with previously untreated resectable G/GEJ tumors (n = 21) received neoadjuvant treatment with one cycle of atezolizumab monotherapy followed by four cycles of atezolizumab plus docetaxel, oxaliplatin and capecitabine. Treatment was well tolerated. There were grade 3 immune-related adverse events in two of 20 patients (10%) but no grade 4 or 5 immune-related adverse events, and all patients underwent resection without treatment-related delays, meeting the primary endpoint of safety and feasibility. Tissue was obtained at multiple time points, allowing analysis of the effects of single-agent anti-programmed cell death ligand 1 (PD-L1) and the subsequent combination with chemotherapy on the TME. Twenty of 21 patients underwent surgery and were evaluable for secondary pathologic response and survival endpoints, and 19 were evaluable for exploratory translational analyses. A major pathologic response (≤10% residual viable tumor) was observed in 14 of 20 (70%, 95% confidence interval 46-88%) patients, including 9 (45%, 95% confidence interval 23-68%) pathologic complete responses. At a median follow-up of 47 months, 13 of 14 responders were alive and disease-free, and five of six nonresponders had died as a result of recurrence. Notably, baseline anti-programmed cell death protein 1 (PD-1)+CD8+ T cell infiltration was significantly higher in responders versus nonresponders, and comparison of TME alterations following anti-PD-L1 monotherapy versus the subsequent combination with chemotherapy showed an increased immune activation on single-agent PD-1/L1 axis blockade. On the basis of these data, monotherapy anti-PD-L1 before its combination with chemotherapy warrants further exploration and validation in a larger cohort of patients with nonmetastatic G/GEJ cancer. ClinicalTrials.gov registration: NCT03448835 .
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Adenocarcinoma , Anticuerpos Monoclonales Humanizados , Neoplasias Esofágicas , Neoplasias Gástricas , Humanos , Terapia Neoadyuvante , Receptor de Muerte Celular Programada 1 , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/patología , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/patología , Unión Esofagogástrica/patología , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Microambiente TumoralRESUMEN
Cells in the tumor microenvironment (TME) influence each other through secretion and sensing of soluble mediators, such as cytokines and chemokines. While signaling of interferon γ (IFNγ) and tumor necrosis factor α (TNFα) is integral to anti-tumor immune responses, our understanding of the spatiotemporal behavior of these cytokines is limited. Here, we describe a single cell transcriptome-based approach to infer which signal(s) an individual cell has received. We demonstrate that, contrary to expectations, CD8+ T cell-derived IFNγ is the dominant modifier of the TME relative to TNFα. Furthermore, we demonstrate that cell pools that show abundant IFNγ sensing are characterized by decreased expression of transforming growth factor ß (TGFß)-induced genes, consistent with IFNγ-mediated TME remodeling. Collectively, these data provide evidence that CD8+ T cell-secreted cytokines should be categorized into local and global tissue modifiers, and describe a broadly applicable approach to dissect cytokine and chemokine modulation of the TME.
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Citocinas , Factor de Necrosis Tumoral alfa , Humanos , Microambiente Tumoral , Interferón gamma , Linfocitos T CD8-positivosRESUMEN
The dysregulated expression of immune checkpoint molecules enables cancer cells to evade immune destruction. While blockade of inhibitory immune checkpoints like PD-L1 forms the basis of current cancer immunotherapies, a deficiency in costimulatory signals can render these therapies futile. CD58, a costimulatory ligand, plays a crucial role in antitumor immune responses, but the mechanisms controlling its expression remain unclear. Using two systematic approaches, we reveal that CMTM6 positively regulates CD58 expression. Notably, CMTM6 interacts with both CD58 and PD-L1, maintaining the expression of these two immune checkpoint ligands with opposing functions. Functionally, the presence of CMTM6 and CD58 on tumor cells significantly affects T cell-tumor interactions and response to PD-L1-PD-1 blockade. Collectively, these findings provide fundamental insights into CD58 regulation, uncover a shared regulator of stimulatory and inhibitory immune checkpoints, and highlight the importance of tumor-intrinsic CMTM6 and CD58 expression in antitumor immune responses.
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Antígeno B7-H1 , Proteínas con Dominio MARVEL , Proteínas de la Mielina , Neoplasias , Linfocitos T , Humanos , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Inmunidad , Inmunoterapia , Neoplasias/tratamiento farmacológico , Neoplasias/inmunología , Linfocitos T/inmunología , Proteínas de la Mielina/metabolismo , Proteínas con Dominio MARVEL/metabolismoRESUMEN
To dissect the effect of neoadjuvant PD-1 and CTLA4 blockade on intratumoral T cells in treatment-naive head and neck squamous cell carcinoma, we analyzed primary tumor immune infiltrates from responding and nonresponding patients. At baseline, a higher ratio between active (4-1BB/OX40+) and inactive regulatory CD4+ T cells was associated with immunotherapy response. Furthermore, upon therapy, this active regulatory T-cell (Treg) population showed a profound decrease in responding patients. In an analogous process, intratumoral dysfunctional CD8+ T cells displayed decreased expression of activity and dysfunction-related genes in responding patients, whereas in clinical nonresponders, natural killer cells showed an increased cytotoxic profile early upon treatment. These data reveal immunologic changes in response to dual PD-1/CTLA4 blockade, including a parallel remodeling of presumed tumor-reactive Treg and CD8+ T-cell compartments in responding patients, and indicate that the presence of activated Tregs at baseline may be associated with response. SIGNIFICANCE: In head and neck squamous cell carcinoma, neoadjuvant PD-1/CTLA4 blockade has shown substantial response rates (20%-35%). As recognition of tumor antigens by T cells appears to be a critical driver of therapy response, a better understanding of alterations in T-cell state that are associated with response and resistance is of importance. This article is featured in Selected Articles from This Issue, p. 2109.
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The lack of suitable models currently hampers our understanding of how the tumor microenvironment responds to immunotherapy treatment. Here, we present a protocol for ex vivo culture of patient-derived tumor fragments (PDTFs). We describe the steps for tumor collection, generation and cryopreservation of PDTFs, and their subsequent thawing. We detail culture of PDTFs and their preparation for analysis. This protocol preserves the tumor microenvironment's composition, architecture, and cellular interactions, which can be perturbed by ex vivo treatment. For complete details on the use and execution of this protocol, please refer to Voabil et al. (2021).1.
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Invasive lobular breast cancer (ILC) is the second most common histological breast cancer subtype, but ILC-specific trials are lacking. Translational research revealed an immune-related ILC subset, and in mouse ILC models, synergy between immune checkpoint blockade and platinum was observed. In the phase II GELATO trial ( NCT03147040 ), patients with metastatic ILC were treated with weekly carboplatin (area under the curve 1.5 mg ml-1 min-1) as immune induction for 12 weeks and atezolizumab (PD-L1 blockade; triweekly) from the third week until progression. Four of 23 evaluable patients had a partial response (17%), and 2 had stable disease, resulting in a clinical benefit rate of 26%. From these six patients, four had triple-negative ILC (TN-ILC). We observed higher CD8+ T cell infiltration, immune checkpoint expression and exhausted T cells after treatment. With this GELATO trial, we show that ILC-specific clinical trials are feasible and demonstrate promising antitumor activity of atezolizumab with carboplatin, particularly for TN-ILC, and provide insights for the design of highly needed ILC-specific trials.
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Carcinoma Lobular , Neoplasias de la Mama Triple Negativas , Humanos , Antígeno B7-H1 , Carboplatino/uso terapéutico , Carcinoma Lobular/tratamiento farmacológico , Carcinoma Lobular/patología , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/patologíaRESUMEN
Ageing is associated with changes in the cellular composition of the immune system. During ageing, hematopoietic stem and progenitor cells (HSPCs) that produce immune cells are thought to decline in their regenerative capacity. However, HSPC function has been mostly assessed using transplantation assays, and it remains unclear how HSPCs age in the native bone marrow niche. To address this issue, we present an in situ single cell lineage tracing technology to quantify the clonal composition and cell production of single cells in their native niche. Our results demonstrate that a pool of HSPCs with unequal output maintains myelopoiesis through overlapping waves of cell production throughout adult life. During ageing, the increased frequency of myeloid cells is explained by greater numbers of HSPCs contributing to myelopoiesis rather than the increased myeloid output of individual HSPCs. Strikingly, the myeloid output of HSPCs remains constant over time despite accumulating significant transcriptomic changes throughout adulthood. Together, these results show that, unlike emergency myelopoiesis post-transplantation, aged HSPCs in their native microenvironment do not functionally decline in their regenerative capacity.
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Células Madre Hematopoyéticas , Mielopoyesis , Adulto , Humanos , Anciano , Mielopoyesis/genética , Médula Ósea , Células de la Médula Ósea , Células MieloidesRESUMEN
By restoring tryptophan, indoleamine 2,3-dioxygenase 1 (IDO1) inhibitors aim to reactivate anti-tumor T cells. However, a phase III trial assessing their clinical benefit failed, prompting us to revisit the role of IDO1 in tumor cells under T cell attack. We show here that IDO1 inhibition leads to an adverse protection of melanoma cells to T cell-derived interferon-gamma (IFNγ). RNA sequencing and ribosome profiling shows that IFNγ shuts down general protein translation, which is reversed by IDO1 inhibition. Impaired translation is accompanied by an amino acid deprivation-dependent stress response driving activating transcription factor-4 (ATF4)high/microphtalmia-associated transcription factor (MITF)low transcriptomic signatures, also in patient melanomas. Single-cell sequencing analysis reveals that MITF downregulation upon immune checkpoint blockade treatment predicts improved patient outcome. Conversely, MITF restoration in cultured melanoma cells causes T cell resistance. These results highlight the critical role of tryptophan and MITF in the melanoma response to T cell-derived IFNγ and uncover an unexpected negative consequence of IDO1 inhibition.
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Melanoma , Triptófano , Humanos , Melanoma/patología , Interferón gamma/metabolismo , Linfocitos T/metabolismo , Indolamina-Pirrol 2,3,-Dioxigenasa/genéticaRESUMEN
Cancer neoantigens that arise from tumor mutations are drivers of tumor-specific T cell responses, but identification of T cell-recognized neoantigens in individual patients is challenging. Previous methods have restricted antigen discovery to selected HLA alleles, thereby limiting the breadth of neoantigen repertoires that can be uncovered. Here, we develop a genetic neoantigen screening system that allows sensitive identification of CD4+ and CD8+ T cell-recognized neoantigens across patients' complete HLA genotypes.