BACKGROUND. Chimeric antigen receptor (CAR) T cells can induce remission in highly refractory leukemia and lymphoma subjects, yet the parameters for achieving sustained relapse-free survival are not fully delineated. METHODS. We analyzed 43 pediatric and young adult subjects participating in a Phase I trial of defined composition CD19CAR T cells (NCT02028455). CAR T cell phenotype, function and expansion, as well as starting material T cell repertoire, were analyzed in relation to therapeutic outcome (defined as achieving complete remission within 63 days) and duration of leukemia free survival and B cell aplasia. RESULTS. These analyses reveal that initial therapeutic failures (n = 5) were associated with attenuated CAR T cell expansion and/or rapid attrition of functional CAR effector cells following adoptive transfer. The CAR T products were similar in phenotype and function when compared to products resulting in sustained remissions. However, the initial apheresed peripheral blood T cells could be distinguished by an increased frequency of LAG-3+/TNF-αlow CD8 T cells and, following adoptive transfer, the rapid expression of exhaustion markers. For the 38 subjects who achieved an initial sustained MRD-neg remission, remission durability correlated with therapeutic products having increased frequencies of TNF-α-secreting CAR CD8+ T cells, and was dependent on a sufficiently high CD19+ antigen load at time of infusion to trigger CAR T cell proliferation. CONCLUSION. These parameters have the potential to prospectively identify patients at risk for therapeutic failure and support the development of approaches to boost CAR T cell activation and proliferation in patients with low levels of CD19 antigen. TRIAL REGISTRATION. ClinicalTrials.gov NCT02028455. FUNDING. Partial funding for this study was provided by Stand Up to Cancer & St. Baldrick’s Pediatric Dream Team Translational Research Grant (SU2C-AACR-DT1113), RO1 CA136551-05, Alex Lemonade Stand Phase I/II Infrastructure Grant, Conquer Cancer Foundation Career Development Award, Washington State Life Sciences Discovery Fund, Ben Towne Foundation, William Lawrence & Blanche Hughes Foundation, and Juno Therapeutics, Inc., a Celgene Company.
Olivia C. Finney, Hannah M. Brakke, Stephanie Rawlings-Rhea, Roxana Hicks, Danielle Doolittle, Marisa Lopez, Robert B. Futrell, Rimas J. Orentas, Daniel Li, Rebecca A. Gardner, Michael C. Jensen
The Epstein Barr virus (EBV) is one of the predominant tumor viruses in humans, but so far no therapeutic or prophylactic vaccination against this transforming pathogen is available. We demonstrated that heterologous prime-boost vaccination with the nuclear antigen 1 of EBV (EBNA1) either targeted to the DEC205 receptor on dendritic cells or expressed from a recombinant modified vaccinia virus Ankara (MVA) vector improved priming of antigen-specific CD4+ T-cell help. This help supported the expansion and maintenance of EBNA1 specific CD8+ T cells that are most efficiently primed by recombinant adenoviruses that encode EBNA1. These combined CD4+ and CD8+ T-cell responses protected from EBNA1 expressing T and B cell lymphomas, including lymphoproliferations that emerge spontaneously after EBNA1 expression. In particular the heterologous EBNA1-expressing adenovirus, boosted by EBNA1-encoding MVA vaccination, demonstrated protection as prophylactic and therapeutic treatment of the respective lymphoma challenges. Therefore, we suggest that such heterologous prime-boost vaccinations should be further explored for clinical development against EBV-associated malignancies as well as symptomatic primary EBV infection.
Julia Rühl, Carmen Citterio, Christine Engelmann, Tracey A. Haigh, Andrzej Dzionek, Johannes H. Dreyer, Rajiv Khanna, Graham S. Taylor, Joanna B. Wilson, Carol S. Leung, Christian Münz
A key mechanism of tumor resistance to immune cells is mediated by expression of peptide-loaded HLA-E in tumor cells, which suppresses natural killer (NK) cell activity via ligation of the NK inhibitory receptor CD94/NKG2A. Gene expression data from approximately 10,000 tumor samples showed widespread HLAE expression, with levels correlating with those of KLRC1 (NKG2A) and KLRD1 (CD94). To bypass HLA-E inhibition, we developed a way to generate highly functional NK cells lacking NKG2A. Constructs containing a single-chain variable fragment derived from an anti-NKG2A antibody were linked to endoplasmic reticulum-retention domains. After retroviral transduction in human peripheral blood NK cells, these NKG2A Protein Expression Blockers (PEBLs) abrogated NKG2A expression. The resulting NKG2Anull NK cells had higher cytotoxicity against HLA-E-expressing tumor cells. Transduction of anti-NKG2A PEBL produced more potent cytotoxicity than interference with an anti-NKG2A antibody and prevented de novo NKG2A expression, without affecting NK cell proliferation. In immunodeficient mice, NKG2Anull NK cells were significantly more powerful than NKG2A+ NK cells against HLA-E-expressing tumors. Thus, NKG2A downregulation evades the HLA-E cancer immune-checkpoint, and increases the anti-tumor activity of NK cell infusions. Because this strategy is easily adaptable to current protocols for clinical-grade immune cell processing, its clinical testing is feasible and warranted.
Takahiro Kamiya, See Voon Seow, Desmond Wong, Murray Robinson, Dario Campana
Background: Systems vaccinology allows cutting-edge analysis of innate biomarkers of vaccine efficacy. We have been exploring novel strategies to shape the adaptive immune response, by targeting innate immune cells through novel immunization routes. Methods: This randomized phase I/II clinical study (n=60 healthy subjects aged 18-45 years old) used transcriptomic analysis to discover early biomarkers of immune response quality after transcutaneous (t.c.), intradermal (i.d.), and intramuscular (i.m.) administration of a trivalent influenza vaccine (TIV season 2012-2013) (1:1:1 ratio). Safety and immunogenicity (hemagglutinin inhibition (HI), microneutralization (MN) antibodies and CD4, CD8 effector T cells) were measured at baseline Day (D)0 and at D21. Blood transcriptome was analyzed at D0 and D1. Results: TIV-specific CD8+GranzymeB+(GRZ) T cells appeared in more individuals immunized by the t.c. and i.d. routes, while immunization by the i.d. and i.m. routes prompted high levels of HI antibody titers and MN against A/H1N1 and A/H3N2 influenza viral strains. The early innate gene signature anticipated immunological outcome by discriminating two clusters of individuals with either distinct humoral or CD8 cytotoxic responses. Several pathways explained this dichotomy confirmed by nine genes and serum level of CXCL10 were correlated with either TIV-specific cytotoxic CD8+GRZ+ T-cell or antibody responses. A logistic regression analysis demonstrated that these nine genes and serum levels of CXCL10 (D1/D0) best foreseen TIV-specific CD8+GRZ+ T-cell and antibody responses at D21. Conclusion: This study provides new insight into the impact of immunization routes and innate signature in the quality of adaptive immune responses.
Eléna Gonçalves, Olivia Bonduelle, Angèle Soria, Pierre Loulergue, Alexandra Rousseau, Marine Cachanado, Henri Bonnabau, Rodolphe Thiebaut, Nicolas Tchitchek, Sylvie Behillil, Sylvie van der Werf, Annika Vogt, Tabassome Simon, Odile Launay, Behazine Combadière
BACKGROUND. Recent genomic and bioinformatic technological advances have made it possible to dissect the immune response to personalized neoantigens encoded by tumor-specific mutations. However, timely and efficient identification of neoantigens is still one of the major obstacles to using personalized neoantigen-based cancer immunotherapy. METHODS. Two different pipelines of neoantigens identification were established in this study: (1) Clinical grade targeted sequencing was performed in patients with refractory solid tumor, and mutant peptides with high variant allele frequency and predicted high HLA-binding affinity were de novo synthesized. (2) An inventory-shared neoantigen peptide library of common solid tumors was constructed, and patients' hotspot mutations were matched to the neoantigen peptide library. The candidate neoepitopes were identified by recalling memory T-cell responses in vitro. Subsequently, neoantigen-loaded dendritic cell vaccines and neoantigen-reactive T cells were generated for personalized immunotherapy in six patients. RESULTS. Immunogenic neo-epitopes were recognized by autologous T cells in 3 of 4 patients who utilized the de novo synthesis mode and in 6 of 13 patients who performed shared neoantigen peptide library, respectively. A metastatic thymoma patient achieved a complete and durable response beyond 29 months after treatment. Immune-related partial response was observed in another patient with metastatic pancreatic cancer. The remaining four patients achieved the prolonged stabilization of disease with a median PFS of 8.6 months. CONCLUSIONS. The current study provided feasible pipelines for neoantigen identification. Implementing these strategies to individually tailor neoantigens could facilitate the neoantigen-based translational immunotherapy research. TRIAL REGSITRATION. ChiCTR.org ChiCTR-OIC-16010092, ChiCTR-OIC-17011275, ChiCTR-OIC-17011913; ClinicalTrials.gov NCT03171220. FUNDING. This work was funded by grants from the National Key Research and Development Program of China (Grant No. 2017YFC1308900), the National Major Projects for “Major New Drugs Innovation and Development” (Grant No.2018ZX09301048-003), the National Natural Science Foundation of China (Grant No. 81672367, 81572329, 81572601), and the Key Research and Development Program of Jiangsu Province (No. BE2017607).
Fangjun Chen, Zhengyun Zou, Juan Du, Shu Su, Jie Shao, Fanyan Meng, Ju Yang, Qiuping Xu, Naiqing Ding, Yang Yang, Qin Liu, Qin Wang, Zhichen Sun, Shujuan Zhou, Shiyao Du, Jia Wei, Baorui Liu
Gastrointestinal stromal tumor (GIST) is the most common human sarcoma, frequently characterized by an oncogenic mutation in the KIT or platelet-derived growth factor receptor alpha (PDGFRA) genes. We performed RNA sequencing of 75 human GIST tumors from 75 patients, comprising the largest cohort of GISTs sequenced to date, in order to discover differences in the immune infiltrates of KIT and PDGFRA-mutant GIST. Through bioinformatics, immunohistochemistry, and flow cytometry, we found that PDGFRA-mutant GISTs harbored more immune cells with increased cytolytic activity when compared to KIT-mutant GISTs. PDGFRA-mutant GISTs expressed many chemokines, such as CXCL14, at a significantly higher level when compared to KIT-mutant GISTs and exhibited more diverse driver-derived neoepitope:HLA binding, both of which may contribute to PDGFRA-mutant GIST immunogenicity. Through machine learning, we generated gene expression-based immune profiles capable of differentiating KIT and PDGFRA-mutant GISTs, and also identified additional immune features of high PD-1 and PD-L1 expressing tumors across all GIST mutational subtypes, which may provide insight into immunotherapeutic opportunities and limitations in GIST.
Gerardo A. Vitiello, Timothy G. Bowler, Mengyuan Liu, Benjamin D. Medina, Jennifer Q. Zhang, Nesteene J. Param, Jennifer K. Loo, Rachel L. Goldfeder, Frederic Chibon, Ferdinand Rossi, Shan Zeng, Ronald P. DeMatteo
Pancreatic ductal adenocarcinoma (PDAC) represents an immune quiescent tumor that is resistant to immune checkpoint inhibitors. Previously, our group has shown that a GM-CSF secreting allogenic pancreatic tumor cell vaccine (GVAX), may prime the tumor microenvironment by inducing intratumoral T-cell infiltration. Here, we show that untreated PDACs express minimal indoleamine-2, 3-dioxygenase (IDO1); however, GVAX therapy induced IDO1 expression on tumor epithelia as well as vaccine-induced tertiary lymphoid aggregates. IDO1 expression plays a role in regulating the polarization of Th1, Th17, and possibly T-regulatory cells in PDAC tumors. IDO1 inhibitor enhanced anti-tumor efficacy of GVAX in a murine model of PDACs. The combination of vaccine and IDO1 inhibitor enhanced intratumoral T-cell infiltration and function, but adding anti-PD-L1 antibody to the combination did not offer further synergy and in fact may have a negative interaction decreasing the number of intratumoral effector T-cells. Additionally, IDO1 inhibitor in the presence of vaccine therapy, did not significantly modulate intratumoral myeloid derived suppressor cells quantitatively, but diminished their suppressive effect on CD8+ proliferation. Our study thus supports the combination of IDO1 inhibitor and vaccine therapy, however, does not support the combination of IDO1 inhibitor and anti-PD-1/PD-L1 antibody for T cell-inflamed tumors such as PDACs treated with vaccine therapy.
Alex B. Blair, Jennifer Kleponis, Dwayne L. Thomas II, Stephen T. Muth, Adrian G. Murphy, Victoria Kim, Lei Zheng
Tregs play a fundamental role in immune tolerance via control of self-reactive effector T cells (Teffs). This function is dependent on maintenance of a high intracellular cAMP concentration. A number of microRNAs are implicated in the maintenance of Tregs. In this study, we demonstrate that peripheral immune tolerance is critically dependent on posttranscriptional repression of the cAMP-hydrolyzing enzyme phosphodiesterase-3b (Pde3b) by microRNA-142-5p (miR-142-5p). In this manner, miR-142-5p acts as an immunometabolic regulator of intracellular cAMP, controlling Treg suppressive function. Mir142 was associated with a super enhancer bound by the Treg lineage–determining transcription factor forkhead box P3 (FOXP3), and Treg-specific deletion of miR-142 in mice (TregΔ142) resulted in spontaneous, lethal, multisystem autoimmunity, despite preserved numbers of phenotypically normal Tregs. Pharmacological inhibition and genetic ablation of PDE3B prevented autoimmune disease and reversed the impaired suppressive function of Tregs in TregΔ142 animals. These findings reveal a critical molecular switch, specifying Treg function through the modulation of a highly conserved, cell-intrinsic metabolic pathway. Modulation of this pathway has direct relevance to the pathogenesis and treatment of autoimmunity and cancer.
Nelomi Anandagoda, Joanna C.D. Willis, Arnulf Hertweck, Luke B. Roberts, Ian Jackson, M. Refik Gökmen, Richard G. Jenner, Jane K. Howard, Graham M. Lord
Parisa Malekzadeh, Anna Pasetto, Paul F. Robbins, Maria R. Parkhurst, Biman C. Paria, Li Jia, Jared J. Gartner, Victoria Hill, Zhiya Yu, Nicholas P. Restifo, Abraham Sachs, Eric Tran, Winifred Lo, Robert P.T. Somerville, Steven A. Rosenberg, Drew C. Deniger
Atypical hemolytic uremic syndrome (aHUS) is frequently associated in humans with loss-of-function mutations in complement-regulating proteins or gain-of-function mutations in complement-activating proteins. Thus, aHUS provides an archetypal complement-mediated disease with which to model new therapeutic strategies and treatments. Herein, we show that, when transferred to mice, an aHUS-associated gain-of-function change (D1115N) to the complement-activation protein C3 results in aHUS. Homozygous C3 p.D1115N (C3KI) mice developed spontaneous chronic thrombotic microangiopathy together with hematuria, thrombocytopenia, elevated creatinine, and evidence of hemolysis. Mice with active disease had reduced plasma C3 with C3 fragment and C9 deposition within the kidney. Therapeutic blockade or genetic deletion of C5, a protein downstream of C3 in the complement cascade, protected homozygous C3KI mice from thrombotic microangiopathy and aHUS. Thus, our data provide in vivo modeling evidence that gain-of-function changes in complement C3 drive aHUS. They also show that long-term C5 deficiency is not accompanied by development of other renal complications (such as C3 glomerulopathy) despite sustained dysregulation of C3. Our results suggest that this preclinical model will allow testing of novel complement inhibitors with the aim of developing precisely targeted therapeutics that could have application in many complement-mediated diseases.
Kate Smith-Jackson, Yi Yang, Harriet Denton, Isabel Y. Pappworth, Katie Cooke, Paul N. Barlow, John P. Atkinson, M. Kathryn Liszewski, Matthew C. Pickering, David Kavanagh, H. Terence Cook, Kevin J. Marchbank