scholarly journals Phenotypic and Functional Analyses Guiding Combination Immune Checkpoint Immunotherapeutic Strategies in HTLV-1 Infection

2021 ◽  
Vol 12 ◽  
Author(s):  
Danielle M. Clements ◽  
Brenndan Crumley ◽  
Glen M. Chew ◽  
Elijah Davis ◽  
Roberta Bruhn ◽  
...  

Human T-cell lymphotropic virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) develops in 1–5% of HTLV-1-infected individuals. Previous studies by us and others have shown that the expression of negative immune checkpoint receptors (NCRs) is significantly increased on CD8 T cells in various chronic viral infections and are associated with poor anti-viral immunity. We have previously identified the differential expression of NCRs on CD8 T cells in blood from patients with HAM/TSP and in central nervous system (CNS) tissues of HTLV-1 infected humanized mice and defined the association with neurological complications. In this study, we determined the co-expression patterns of several key NCRs (PD-1, TIGIT, TIM-3, and LAG-3) and their cognate ligands in HTLV-1 infection and assessed how combination strategies targeting these pathways would impact HTLV-1-specific CD8 T-cell effector functions as an approach to reduce CNS disease outcomes. We found that global CD8 T cells from HAM/TSP patients co-express multiple NCRs at significantly higher frequencies than asymptomatic carriers (AC). Moreover, NCR ligands (PVR and PD-LI) on both plasmacytoid and myeloid dendritic cells were also expressed at higher frequencies in HAM/TSP compared to AC. In both AC and HAM/TSP subjects, combination dual PD-L1/TIGIT or triple PD-L1/TIGIT/TIM-3 blockade with monoclonal antibodies resulted in increases in intracellular cytokine expression in CD8 T cells after virus stimulation, particularly CD107a, a marker of degranulation, and TNF-α, a key cytokine that can directly inhibit viral replication. Interestingly, almost all blockade combinations resulted in reduced IL-2+ HTLV-1-specific CD8 T cell frequencies in HAM/TSP subjects, but not in AC. These results define a novel combinatorial NCR immunotherapeutic blockade strategy to reduce HAM/TSP disease burden.

Blood ◽  
2008 ◽  
Vol 112 (6) ◽  
pp. 2400-2410 ◽  
Author(s):  
Yoshimi Enose-Akahata ◽  
Unsong Oh ◽  
Christian Grant ◽  
Steven Jacobson

AbstractCD8+ T cells contribute to central nervous system inflammation in human T-cell lymphotropic virus type I (HTLV-I)–associated myelopathy/tropical spastic paraparesis (HAM/TSP). We analyzed CD8+ T-cell dysfunction (degranulation and IFN-γ production) and have demonstrated that CD8+ T cells of patients with HAM/TSP (HAM/TSP patients) spontaneously degranulate and express IFN-γ in ex vivo unstimulated culture. CD8+ T cells of HTLV-I asymptomatic carriers and healthy donors did not. Spontaneous degranulation was detected in Tax11-19/HLA-A*201 tetramer+ cells, but not in CMV pp65 tetramer+ cells. Interestingly, degranulation and IFN-γ production in CD8+ T cells was induced by coculture with autologous CD14+ cells, but not CD4+ T cells, of HAM/TSP patients, which correlated with proviral DNA load in CD14+ cells of infected patients. Moreover, the expression of IL-15, which induced degranulation and IFN-γ production in infected patients, was enhanced on surface of CD14+ cells in HAM/TSP patients. Blockade of MHC class I and IL-15 confirmed these results. Thus, CD8+ T-cell dysregulation was mediated by both virus infection and enhanced IL-15 on CD14+ cells in HAM/TSP patients. Despite lower viral expression than in CD4+ T cells, HTLV-I–infected or –activated CD14+ cells may be a heretofore important but under recognized reservoir particularly in HAM/TSP patients.


2005 ◽  
Vol 79 (15) ◽  
pp. 9419-9429 ◽  
Author(s):  
Nicole E. Miller ◽  
Jennifer R. Bonczyk ◽  
Yumi Nakayama ◽  
M. Suresh

ABSTRACT Although it is well documented that CD8 T cells play a critical role in controlling chronic viral infections, the mechanisms underlying the regulation of CD8 T-cell responses are not well understood. Using the mouse model of an acute and chronic lymphocytic choriomeningitis virus (LCMV) infection, we have examined the relative importance of peripheral T cells and thymic emigrants in the elicitation and maintenance of CD8 T-cell responses. Virus-specific CD8 T-cell responses were compared between mice that were either sham thymectomized or thymectomized (Thx) at ∼6 weeks of age. In an acute LCMV infection, thymic deficiency did not affect either the primary expansion of CD8 T cells or the proliferative renewal and maintenance of virus-specific lymphoid and nonlymphoid memory CD8 T cells. Following a chronic LCMV infection, in Thx mice, although the initial expansion of CD8 T cells was normal, the contraction phase of the CD8 T-cell response was exaggerated, which led to a transient but striking CD8 T-cell deficit on day 30 postinfection. However, the virus-specific CD8 T-cell response in Thx mice rebounded quickly and was maintained at normal levels thereafter, which indicated that the peripheral T-cell repertoire is quite robust and capable of sustaining an effective CD8 T-cell response in the absence of thymic output during a chronic LCMV infection. Taken together, these findings should further our understanding of the regulation of CD8 T-cell homeostasis in acute and chronic viral infections and might have implications in the development of immunotherapy.


2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A788-A788
Author(s):  
Xiuning Le ◽  
Minghao Dang ◽  
Venkatesh Hegde ◽  
Bo Jiang ◽  
Ravaen Slay ◽  
...  

BackgroundHuman papillomavirus (HPV)-positive head and neck squamous cell carcinoma (HPV+ HNSCC) is a disease that has moderate response to anti-PD-1/L1 immune checkpoint blockade, with the response rates less than 20% and median progression-free survival less than 3 months. A greater understanding of tumor intrinsic and extrinsic factors that restrict anti-tumor immunity in the tumor immune microenvironment (TIME) is needed to identify other immune checkpoints to enhance therapeutic efficacy.MethodsTwo cohorts (TCGA n=72 and a separate cohort n=84) of surgically resected, treatment-naïve HPV+ HNSCC with RNA-seq were analyzed to understand the immune features. In addition, single-cell RNA-seq and TCR-seq were performed on 18 cases to further delineate the immune molecules' interactions. An immune-competent murine HPV+ HNSCC model was used to preliminarily evaluate the therapeutic efficacy.ResultsIn two bulk-sequenced HPV+ HNSCC cohorts, TIGIT ligands PVR and NECTIN2 were found to associate with an epithelial-to-mesenchymal gene expression signature, suppression of IFNα and IFNγ signaling, a stromal-enriched or immune-excluded TIME, and poor survival. Single-cell RNA-seq of over 72,000 cells of HPV+ HNSCC revealed that the PVR/NECTIN ligand TIGIT was highly prevalent in T-cells (34%), significantly higher than PD1- (20%, p<0.01). There is an enrichment of cell-cell interactions mediated by TIGIT-PVR/NECTIN2 in the TIME of HPV+HNSCC versus normal tonsil. TIGIT was the most differentially upregulated immune checkpoint on clonally expanded CD8+T-cells and was abundant on antigen-experienced, tissue-resident memory CD8+T-cell and T-regulatory subsets. TIGIT ligands PVR, NECTIN1, and NECTIN2 were abundant on mature regulatory dendritic cells (DCs), immunosuppressive plasmacytoid (p)DCs, and macrophages, respectively. TIGIT and PD-1 co-blockade in the mEER syngeneic murine model significantly reduced tumor growth, improved survival, restored effector function of HPV16E7-specific CD8+T cells, natural killer cells, and DCs, and conferred tumor re-challenge protection.ConclusionsTIGIT-PVR/NECTIN receptors/ligands are more abundant than PD-1/L1 in the TIME of HPV+ HNSCC. Co-blockade of TIGIT and PD-1 immune checkpoints enhanced anti-tumor efficacy in a CD8+ T-cell-dependent manner and conferred long-term immune protection in a murine model. Our study nominates TIGIT as a therapeutic target for HPV+ HNSCC.


2005 ◽  
Vol 202 (5) ◽  
pp. 673-685 ◽  
Author(s):  
Andrew W. Sylwester ◽  
Bridget L. Mitchell ◽  
John B. Edgar ◽  
Cara Taormina ◽  
Christian Pelte ◽  
...  

Human cytomegalovirus (HCMV) infections of immunocompetent hosts are characterized by a dynamic, life-long interaction in which host immune responses, particularly of T cells, restrain viral replication and prevent disease but do not eliminate the virus or preclude transmission. Because HCMV is among the largest and most complex of known viruses, the T cell resources committed to maintaining this balance have never been characterized completely. Here, using cytokine flow cytometry and 13,687 overlapping 15mer peptides comprising 213 HCMV open reading frames (ORFs), we found that 151 HCMV ORFs were immunogenic for CD4+ and/or CD8+ T cells, and that ORF immunogenicity was influenced only modestly by ORF expression kinetics and function. We further documented that total HCMV-specific T cell responses in seropositive subjects were enormous, comprising on average ∼10% of both the CD4+ and CD8+ memory compartments in blood, whereas cross-reactive recognition of HCMV proteins in seronegative individuals was limited to CD8+ T cells and was rare. These data provide the first glimpse of the total human T cell response to a complex infectious agent and will provide insight into the rules governing immunodominance and cross-reactivity in complex viral infections of humans.


2020 ◽  
Author(s):  
Zhanwei Wang ◽  
Xi Yang ◽  
Jiamin Xu ◽  
Yuefen Pan ◽  
Junjun Shen ◽  
...  

Abstract Objective: This study investigated the gene expression patterns associated with tumor-infiltrating CD4+ and CD8+ T cells in invasive breast carcinomas.Methods: The gene expression data and corresponding clinical phenotype data from the Cancer Genome Atlas Breast Invasive Carcinoma (TCGA-BRCA) were downloaded. The stromal and immune score were calculated using ESTIMATE. The differentially expressed genes (DEGs) with a high vs. low stromal score and a high vs. low immune score were screened and then functionally enriched. The tumor-infiltrating immune cells were investigated using the Cibersort algorithm, and the CD4+ and CD8+ T cell-related genes were identified using a Spearman correlation test of infiltrating abundance with the DEGs. Moreover, the miRNA-mRNA pairs and lncRNA-miRNA pairs were predicted to construct the competing endogenous RNAs (ceRNA) network. Kaplan-Meier (K-M) survival curves were also plotted.Results: In total, 478 DEGs with a high vs. low stromal score and 796 DEGs with a high vs. low immune score were identified. In addition, 39 CD4+ T cell-related genes and 78 CD8+ T cell-related genes were identified; of these, 14 genes were significantly associated with the prognosis of BRCA patients. Moreover, for CD4+ T cell-related genes, the chr22-38_28785274-29006793.1-–miR-34a/c-5p–CAPN6 axis was identified from the ceRNA network, whereas the chr22-38_28785274-29006793.1–miR-494-3p–SLC9A7 axis was identified for CD8+ T cell-related genes.Conclusions: The chr22-38_28785274-29006793.1-–miR-34a/c-5p–CAPN6 axis and the chr22-38_28785274-29006793.1–miR-494-3p–SLC9A7 axis might regulate cellular activities associated with CD4+ and CD8+ T cell infiltration, respectively, in BRCA.


2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A338-A338
Author(s):  
Berengere Salome ◽  
John Sfakianos ◽  
Andrew Charap ◽  
Adam Farkas ◽  
Daniel Geanon ◽  
...  

BackgroundBladder cancer is characterized by a poor prognosis, with muscle-invasive cases harboring a 34–76% 10-year recurrence-free survival rate.1 Neoadjuvant PD-1/PD-L1 blockade strategies have recently been approved by the US Food and Drug Administration for bladder cancer treatment, yet only achieving a complete response rate of 31–37%, thereby suggesting additional mechanisms of resistance.2 HLA-E is a known inhibitor of NKG2A+ CD8 T cells and NK cell responses. A monoclonal antibody binding to the NKG2A receptor has been developed and proven to restore CD8 T cell and NK cell responses in head and neck cancer, with ongoing clinical trials across multiple tumor indications.3 4 We evaluated the potential role of the HLA-E/NKG2A inhibitory pathway in modulating T cell immunity in bladder cancer.MethodsCyTOF was performed on CD8+ T cells from fresh bladder tumors (n=6), as well as on expanded CD8+ T cells from bladder-draining lymph nodes (n=11) and tumors (n=8). Flow cytometry (n=25) and single-cell RNA-sequencing (scRNAseq) (n=13) were performed on cells from fresh bladder tumors.ResultsMechanisms of tumor escape from CD8+ T cell recognition include impairment of antigen presentation. Accordingly, we found a significant reduction of HLA class I expression on tumors. However, expression of DNAM-1-activating ligands (e.g. CD112,CD155) on bladder tumors was retained, indicating a possible role for TCR-independent activation pathways traditionally ascribed to natural killer (NK) cells. Using mass cytometry and scRNAseq, we observed that acquisition of NKG2A on tumor-derived PD-1+ CD8+ T cells promotes tissue-resident memory features alongside diminished CD28 expression and significantly weaker sensitivity to CD3/CD28-signaling. However, NKG2A+ CD8 T cells possess a proliferative advantage with enhanced expression of DNAM-1 and cytolytic machinery.Strikingly, we found that NKG2A+PD-1+ CD8 T cells are strongly activated in response to HLA class I-deficient tumors compared to their NKG2A- PD-1+ CD8 T cell counterparts. TCR-independent NK-like function by NKG2A+ CD8 T cell is partly mediated by the DNAM-1 pathway and inhibited by HLA-E. NKG2A+ CD8 T cell functions are restored upon NKG2A blockade, where efficiency positively correlates with HLA-E expression on bladder tumors.ConclusionsCollectively, our data indicate that NKG2A+ CD8 T cells display a strong capacity for TCR-independent activation that enables them to circumvent bladder tumor evasion mechanisms. NKG2A+ CD8 T cells lack expression of CD28 suggesting a lower susceptibility to PD-1-mediated inhibiton. Our data suggest a need for thorough reappraisal of current protocols that assess CD8 T cell exhaustion and for strategies to restore their antitumor functions.ReferencesSanli O, Dobruch J, Knowles MA, Burger M, Alemozaffar M, Nielsen ME, Lotan Y. Bladder cancer. Nat Rev Dis Primers 2017 April 13;3:17022. doi: 10.1038/nrdp.2017.22. PMID: 28406148. Rouanne M, Bajorin DF, Hannan R, Galsky MD, Williams SB, Necchi A, Sharma P, Powles T. Rationale and outcomes for neoadjuvant immunotherapy in urothelial carcinoma of the bladder. Eur Urol Oncol 2020 December;3(6):728–738. doi: 10.1016/j.euo.2020.06.009. Epub 2020 Nov 8. PMID: 33177001. André P, Denis C, Soulas C, Bourbon-Caillet C, Lopez J, Arnoux T, Bléry M, Bonnafous C, Gauthier L, Morel A, Rossi B, Remark R, Breso V, Bonnet E, Habif G, Guia S, Lalanne AI, Hoffmann C, Lantz O, Fayette J, Boyer-Chammard A, Zerbib R, Dodion P, Ghadially H, Jure-Kunkel M, Morel Y, Herbst R, Narni-Mancinelli E, Cohen RB, Vivier E. Anti-NKG2A mAb is a checkpoint inhibitor that promotes anti-tumor immunity by unleashing both T and NK Cells. Cell 2018 December 13;175(7):1731–1743.e13. doi: 10.1016/j.cell.2018.10.014. Epub 2018 Nov 29. PMID: 30503213; PMCID: PMC6292840. van Hall T, André P, Horowitz A, Ruan DF, Borst L, Zerbib R, Narni-Mancinelli E, van der Burg SH, Vivier E. Monalizumab: inhibiting the novel immune checkpoint NKG2A. J Immunother Cancer 2019 October 17;7(1):263. doi: 10.1186/s40425-019-0761-3. PMID: 31623687; PMCID: PMC6798508.


2021 ◽  
Vol 12 ◽  
Author(s):  
Lydia Scharf ◽  
Christina B. Pedersen ◽  
Emil Johansson ◽  
Jacob Lindman ◽  
Lars R. Olsen ◽  
...  

HIV-2 is less pathogenic compared to HIV-1. Still, disease progression may develop in aviremic HIV-2 infection, but the driving forces and mechanisms behind such development are unclear. Here, we aimed to reveal the immunophenotypic pattern associated with CD8 T-cell pathology in HIV-2 infection, in relation to viremia and markers of disease progression. The relationships between pathological differences of the CD8 T-cell memory population and viremia were analyzed in blood samples obtained from an occupational cohort in Guinea-Bissau, including HIV-2 viremic and aviremic individuals. For comparison, samples from HIV-1- or dually HIV-1/2-infected and seronegative individuals were obtained from the same cohort. CD8 T-cell exhaustion was evaluated by the combined expression patterns of activation, stimulatory and inhibitory immune checkpoint markers analyzed using multicolor flow cytometry and advanced bioinformatics. Unsupervised multidimensional clustering analysis identified a cluster of late differentiated CD8 T-cells expressing activation (CD38+, HLA-DRint/high), co-stimulatory (CD226+/-), and immune inhibitory (2B4+, PD-1high, TIGIThigh) markers that distinguished aviremic from viremic HIV-2, and treated from untreated HIV-1-infected individuals. This CD8 T-cell population displayed close correlations to CD4%, viremia, and plasma levels of IP-10, sCD14 and beta-2 microglobulin in HIV-2 infection. Detailed analysis revealed that aviremic HIV-2-infected individuals had higher frequencies of exhausted TIGIT+ CD8 T-cell populations lacking CD226, while reduced percentage of stimulation-receptive TIGIT-CD226+ CD8 T-cells, compared to seronegative individuals. Our results suggest that HIV-2 infection, independent of viremia, skews CD8 T-cells towards exhaustion and reduced co-stimulation readiness. Further knowledge on CD8 T-cell phenotypes might provide help in therapy monitoring and identification of immunotherapy targets.


Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 2761-2761
Author(s):  
Nicholas J. Hess ◽  
David Turicek ◽  
Amy Hudson ◽  
Peiman Hematti ◽  
Jenny Gumperz ◽  
...  

Abstract Acute graft-vs-host disease (aGVHD) and cancer relapse remain the primary complications following an allogeneic hematopoietic stem cell transplantation (allo-HSCT) for malignant blood disorders. While post-transplant cyclophosphamide combined with standard GVHD prophylaxis has greatly reduced the overall prevalence and severity of aGVHD, relapse rates remain a concern. There is thus a need to identify the specific human T cell populations mediating GVHD vs GVL activity as a means to develop targeted therapeutics capable of controlling aGVHD without inhibiting GVL activity. In this study, we identify a novel human T cell population that develops after transplant that is predictive and sufficient for GVHD pathology. To determine the role of human T cell populations in aGVHD, we performed xenogeneic transplantation studies using primary human graft tissue from a variety of sources (peripheral blood, G-CSF mobilized peripheral blood, bone marrow and umbilical cord blood) in addition to collecting primary human aGVHD blood samples from our clinic. Using the LD50 dose of human graft tissue, we identified a novel mature CD4 +/CD8αβ + double positive (DP) T cell population that only developed after transplantation. The development of this population was further confirmed in aGVHD patients from our clinic. The presence of DP T cells, irrespective of graft source, was also predictive of lethal GVHD in as early as one week after xenogeneic transplantation. To identify the origin of DP T cells, we transplanted isolated human CD4 or CD8 T cells into mice which showed that DP T cells only arise from the CD8 pool. Furthermore, re-transplantation of flow-sorted CD8 T cells from GVHD mice did not reveal a 2nd wave of DP T cell differentiation. This data, in addition to their highly proliferative state, suggests that DP T cells represent highly activated CD8 T cell clones. The ability of these CD8-derived DP T cells to gain CD4 expression coincides with their co-expression of both RUNX3 and THPOK, the master transcription factors of the CD8 and CD4 lineages respectively, that classically repress each other. Intracellular cytokine staining also revealed that DP T cells are the primary activated T cell population in xenogeneic GVHD, secreting both modulatory and cytotoxic cytokines (e.g. IFNγ, IL-17A, IL-22, perforin and granzyme). Ex vivo re-stimulation or re-transplantation of flow-sorted DP T cells showed that this T cell population is capable of dividing and expanding independent of CD4 and CD8 single positive T cells with the majority of the isolated DP T cells retaining their co-expression of CD4 and CD8. Finally, transplantation of either isolated human peripheral blood CD4 or CD8 T cell populations were capable of causing lethal GVHD. Conversely, re-transplantation of flow-sorted DP, CD8 or CD4 T cells from GVHD mice revealed that DP and CD4 T cells are sufficient to mediate GVHD pathology but re-transplanted CD8 T cell are not. This correlates with the absence of DP T cell differentiation in that re-transplanted CD8 population. The differentiation of DP T cells from chronically activated CD8 T cells represents a novel mechanism of GVHD pathology not previously described. The presence of DP T cells in other chronic inflammatory human diseases also suggests a broader pathology mediated by DP T cells. Further understanding of DP T cell differentiation and pathology may lead to targeted prophylaxis and/or treatment regimens for aGVHD and other human chronic inflammatory diseases. Figure 1 Figure 1. Disclosures Capitini: Nektar Therapeutics: Honoraria; Novartis: Honoraria.


2021 ◽  
Author(s):  
Joy A. Pai ◽  
Andrew Chow ◽  
Jennifer Sauter ◽  
Marissa Mattar ◽  
Hira Rizvi ◽  
...  

Paired T cell receptor and RNA single cell sequencing (scTCR/RNA-seq) has allowed for enhanced resolution of clonal T cell dynamics in cancer. Here, we report a scTCR/RNA-seq dataset of 162,062 single T cells from 31 tissue regions, including tumor, adjacent normal tissues, and lymph nodes (LN), from three patients who underwent resections for progressing lung cancers after immune checkpoint blockade (ICB). We found marked regional heterogeneity in tumor persistence that was associated with heterogeneity in CD4 and CD8 T cell phenotypes; regions with persistent cancer cells were enriched for follicular helper CD4 T cells (TFH), regulatory T cells (Treg), and exhausted CD8 T cells. Clonal analysis demonstrated that highly-expanded T cell clones were predominantly of the CD8 subtype, were ubiquitously present across all sampled regions, found in the peripheral circulation, and expressed gene signatures of 'large' and 'dual-expanded' clones that have been predictive of response to ICB. Longitudinal tracking of CD8 T cell clones in the peripheral blood revealed that the persistence of ubiquitous CD8 T cell clones, as well as phenotypically distinct clones with tumor-reactive features, correlated with systemic tumor control. Finally, tracking CD8 T cell clones across tissues revealed the presence of TCF-1+ precursor exhausted CD8 T cells in tumor draining LNs that were clonally linked to expanded exhausted CD8 T cells in tumors. Altogether, this comprehensive scTCR/RNA-seq dataset with regional, longitudinal, and clonal resolution provides fundamental insights into the tissue distribution, persistence, and differentiation trajectories of ICB-responsive T cells that underlie clinical responses to ICB.


Blood ◽  
2011 ◽  
Vol 117 (18) ◽  
pp. 4805-4815 ◽  
Author(s):  
Takuya Yamamoto ◽  
David A. Price ◽  
Joseph P. Casazza ◽  
Guido Ferrari ◽  
Martha Nason ◽  
...  

Abstract A highly complex network of coinhibitory and costimulatory receptors regulates the outcome of virus-specific CD8+ T-cell responses. Here, we report on the expression patterns of multiple inhibitory receptors on HIV-specific, cytomegalovirus-specific, and bulk CD8+ T-cell memory populations. In contrast to cytomegalovirus-specific CD8+ T cells, the majority of HIV-specific CD8+ T cells exhibited an immature phenotype and expressed Programmed Death-1, CD160 and 2B4 but not lymphocyte activation gene-3. Notably, before antiretroviral therapy, simultaneous expression of these negative regulators correlated strongly with both HIV load and impaired cytokine production. Suppression of HIV replication by antiretroviral therapy was associated with reduced surface expression of inhibitory molecules on HIV-specific CD8+ T cells. Furthermore, in vitro manipulation of Programmed Death-1 and 2B4 inhibitory pathways increased the proliferative capacity of HIV-specific CD8+ T cells. Thus, multiple coinhibitory receptors can affect the development of HIV-specific CD8+ T-cell responses and, by extension, represent potential targets for new immune-based interventions in HIV-infected persons.


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