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PloS One 2016Ebola virus (EBOV), a member of the Filoviridae that can cause severe hemorrhagic fever in humans and nonhuman primates, poses a significant threat to the public health....
Ebola virus (EBOV), a member of the Filoviridae that can cause severe hemorrhagic fever in humans and nonhuman primates, poses a significant threat to the public health. Currently, there are no licensed vaccines or therapeutics to prevent and treat EBOV infection. Several vaccines based on the EBOV glycoprotein (GP) are under development, including vectored, virus-like particles, and protein-based subunit vaccines. We previously demonstrated that a subunit vaccine containing the extracellular domain of the Ebola ebolavirus (EBOV) GP fused to the Fc fragment of human IgG1 (EBOVgp-Fc) protected mice against EBOV lethal challenge. Here, we show that the EBOVgp-Fc vaccine formulated with QS-21, alum, or polyinosinic-polycytidylic acid-poly-L-lysine carboxymethylcellulose (poly-ICLC) adjuvants induced strong humoral immune responses in guinea pigs. The vaccinated animals developed anti-GP total antibody titers of approximately 105-106 and neutralizing antibody titers of approximately 103 as assessed by a BSL-2 neutralization assay based on vesicular stomatitis virus (VSV) pseudotypes. The poly-ICLC formulated EBOVgp-Fc vaccine protected all the guinea pigs against EBOV lethal challenge performed under BSL-4 conditions whereas the same vaccine formulated with QS-21 or alum only induced partial protection. Vaccination with a mucin-deleted EBOVgp-Fc construct formulated with QS-21 adjuvant did not have a significant effect in anti-GP antibody levels and protection against EBOV lethal challenge compared to the full-length GP construct. The bulk of the humoral response induced by the EBOVgp-Fc vaccine was directed against epitopes outside the EBOV mucin region. Our findings indicate that different adjuvants can eliciting varying levels of protection against lethal EBOV challenge in guinea pigs vaccinated with EBOVgp-Fc, and suggest that levels of total anti-GP antibodies elicit by protein-based GP subunit vaccines do not correlate with protection. Our data further support the development of Fc fusions of GP as a candidate vaccine for human use.
Topics: Adjuvants, Immunologic; Alum Compounds; Animals; Antibodies, Neutralizing; Antibodies, Viral; Carboxymethylcellulose Sodium; Ebola Vaccines; Ebolavirus; Female; Guinea Pigs; Hemorrhagic Fever, Ebola; Humans; Immunoglobulin Fc Fragments; Male; Poly I-C; Polylysine; Recombinant Fusion Proteins; Saponins; Vaccines, Synthetic; Viral Envelope Proteins
PubMed: 27622456
DOI: 10.1371/journal.pone.0162446 -
JCI Insight Apr 2018Low-grade gliomas (LGGs) are the most common brain tumor affecting children. We recently reported an early phase clinical trial of a peptide-based vaccine, which...
Low-grade gliomas (LGGs) are the most common brain tumor affecting children. We recently reported an early phase clinical trial of a peptide-based vaccine, which elicited consistent antigen-specific T cell responses in pediatric LGG patients. Additionally, we observed radiologic responses of stable disease (SD), partial response (PR), and near-complete/complete response (CR) following therapy. To identify biomarkers of clinical response in peripheral blood, we performed RNA sequencing on PBMC samples collected at multiple time points. Patients who showed CR demonstrated elevated levels of T cell activation markers, accompanied by a cytotoxic T cell response shortly after treatment initiation. At week 34, patients with CR demonstrated both IFN signaling and Poly-IC:LC adjuvant response patterns. Patients with PR demonstrated a unique, late monocyte response signature. Interestingly, HLA-V expression, before or during therapy, and an early monocytic hematopoietic response were strongly associated with SD. Finally, low IDO1 and PD-L1 expression before treatment and early elevated levels of T cell activation markers were associated with prolonged progression-free survival. Overall, our data support the presence of unique peripheral immune patterns in LGG patients associated with different radiographic responses to our peptide vaccine immunotherapy. Future clinical trials, including our ongoing phase II LGG vaccine immunotherapy, should monitor these response patterns.
Topics: Adolescent; Adult; B7-H1 Antigen; Biomarkers, Tumor; Brain Neoplasms; Cancer Vaccines; Carboxymethylcellulose Sodium; Child; Follow-Up Studies; Glioma; Humans; Immunogenicity, Vaccine; Immunotherapy; Indoleamine-Pyrrole 2,3,-Dioxygenase; Lymphocyte Activation; Male; Monocytes; Poly I-C; Polylysine; Progression-Free Survival; Sequence Analysis, RNA; Survival Analysis; T-Lymphocytes; Vaccines, Subunit; Young Adult
PubMed: 29618666
DOI: 10.1172/jci.insight.98791 -
Experimental Hematology & Oncology 2018The optimal strategy for vaccination to induce CD8 T cell responses against WT1 is not known.
BACKGROUND
The optimal strategy for vaccination to induce CD8 T cell responses against WT1 is not known.
METHODS
A pilot randomized study in HLA-A02 patients to receive vaccination with WT1 in Montanide or in poly ICLC, a TLR3 agonist, to explore the novel immune adjuvant was conducted. Seven patients were randomized. Four patients received WT1 in Montanide, and three with WT1 in poly ICLC. Five patients were in morphologic remission and two had residual morphologic disease at the study entry.
RESULTS
All patients finished the induction phase without any major toxicity except mild transient local injection reaction. One patient on the Montanide arm developed aseptic ulceration at two vaccine sites which healed without antibiotics. Three of 4 patients on the Montanide arm had a decreased expression of WT1 after WT1 vaccination, and two of them demonstrated generation of WT1-specific cytotoxic CD8 T cell responses with biased TCR beta chain enrichment. In contrast, no obvious WT1-specific immune responses were detected in two patients on the poly ICLC arm, nor was there clonal enrichment by TCR alpha/beta sequencing; however, these patients did also have decreased WT1 expression and remained in remission several years after the initiation of treatment.
CONCLUSIONS
WT1 peptide vaccine with Montanide as an adjuvant induces detectable WT1-specific CD8 T cell responses with clonal TCR enrichment, which may be capable of controlling leukemia recurrence in the setting of minimal residual disease. Poly ICLC may induce anti-leukemic activity in the absence of detectable WT1 specific CD8 T cell responses. NCT01842139, 7/3/2012 retrospectively registered; https://clinicaltrials.gov/ct2/show/NCT01842139.
PubMed: 29344432
DOI: 10.1186/s40164-018-0093-x -
Journal For Immunotherapy of Cancer Jun 2020In vivo targeting of human papillomavirus (HPV) derived antigens to dendritic cells might constitute an efficient immunotherapeutic strategy against cervical cancer. In...
BACKGROUND
In vivo targeting of human papillomavirus (HPV) derived antigens to dendritic cells might constitute an efficient immunotherapeutic strategy against cervical cancer. In previous works, we have shown that the extra domain A from murine fibronectin (mEDA) can be used to target antigens to toll-like receptor 4 (TLR4) expressing dendritic cells and induce strong antigen-specific immune responses. In the present study, we have produced a bivalent therapeutic vaccine candidate consisting of the human EDA (hEDA) fused to E7 proteins from HPV16 and HPV18 (hEDA-HPVE7-16/18) and evaluate its potential as a therapeutic vaccine against cervical cancer.
MATERIALS AND METHODS
Recombinant fusion proteins containing HPV E7 proteins from HPV16 and HPV18 virus subtypes fused to hEDA were produced and tested in vitro on their capacity to bind TLR4 and induce the production of tumor necrosis factor-α or interleukin (IL)-12 by human monocytes and dendritic cells. The immunogenicity and potential therapeutic activity of the vaccine in combination with cisplatin or with the TLR3 agonist molecules polyinosinic-polycytidylic acid (Poly IC) or Poly ICLC was evaluated in mice bearing subcutaneous or genital orthotopic HPV16 TC-1 tumors.
RESULTS
hEDA-HPVE7-16/18 prototype vaccine binds human TLR4 and stimulate TLR4-dependent signaling pathways and IL-12 production by human monocyte-derived dendritic cell. Vaccination with hEDA-HPVE7-16/18 induced strong HPVE7-specific Cytotoxic T lymphocyte (CTL) responses and eliminated established tumors in the TC-1-based tumor model. The antitumor efficacy was significantly improved by combining the fusion protein with cisplatin or with the TLR-3 ligand Poly IC and especially with the stabilized analog Poly ICLC. Moreover, hEDA-HPVE7-16/18+Poly ICLC induced full tumor regression in 100% of mice bearing orthotopic genital HPV tumors.
CONCLUSION
Our results suggest that this therapeutic vaccine formulation may be an effective treatment for cervical tumors that do not respond to current therapies.
Topics: Animals; Cancer Vaccines; DNA-Binding Proteins; Dendritic Cells; Female; Fibronectins; Human papillomavirus 16; Human papillomavirus 18; Humans; Mice; Mice, Inbred C57BL; Neoplasms, Experimental; Oncogene Proteins, Viral; Papillomavirus E7 Proteins; Papillomavirus Infections; T-Lymphocytes, Cytotoxic
PubMed: 32581060
DOI: 10.1136/jitc-2020-000704 -
Clinical Cancer Research : An Official... Jan 2015WHO grade 2 low-grade gliomas (LGG) with high risk factors for recurrence are mostly lethal despite current treatments. We conducted a phase I study to evaluate the... (Clinical Trial)
Clinical Trial
PURPOSE
WHO grade 2 low-grade gliomas (LGG) with high risk factors for recurrence are mostly lethal despite current treatments. We conducted a phase I study to evaluate the safety and immunogenicity of subcutaneous vaccinations with synthetic peptides for glioma-associated antigen (GAA) epitopes in HLA-A2(+) adults with high-risk LGGs in the following three cohorts: (i) patients without prior progression, chemotherapy, or radiotherapy (RT); (ii) patients without prior progression or chemotherapy but with prior RT; and (iii) recurrent patients.
EXPERIMENTAL DESIGN
GAAs were IL13Rα2, EphA2, WT1, and Survivin. Synthetic peptides were emulsified in Montanide-ISA-51 and given every 3 weeks for eight courses with intramuscular injections of poly-ICLC, followed by q12 week booster vaccines.
RESULTS
Cohorts 1, 2, and 3 enrolled 12, 1, and 10 patients, respectively. No regimen-limiting toxicity was encountered except for one case with grade 3 fever, fatigue, and mood disturbance (cohort 1). ELISPOT assays demonstrated robust IFNγ responses against at least three of the four GAA epitopes in 10 and 4 cases of cohorts 1 and 3, respectively. Cohort 1 patients demonstrated significantly higher IFNγ responses than cohort 3 patients. Median progression-free survival (PFS) periods since the first vaccine are 17 months in cohort 1 (range, 10-47+) and 12 months in cohort 3 (range, 3-41+). The only patient with large astrocytoma in cohort 2 has been progression-free for more than 67 months since diagnosis.
CONCLUSION
The current regimen is well tolerated and induces robust GAA-specific responses in WHO grade 2 glioma patients. These results warrant further evaluations of this approach. Clin Cancer Res; 21(2); 286-94. ©2014 AACR.
Topics: Adult; Antigens, Neoplasm; Antineoplastic Combined Chemotherapy Protocols; CD8-Positive T-Lymphocytes; Cancer Vaccines; Carboxymethylcellulose Sodium; Disease-Free Survival; Female; Glioma; Humans; Male; Middle Aged; Neoplasm Grading; Pilot Projects; Poly I-C; Polylysine; Treatment Outcome; Vaccines, Subunit
PubMed: 25424847
DOI: 10.1158/1078-0432.CCR-14-1790 -
Cancers Apr 2019Immunotherapy, including therapeutic vaccines, is increasingly being developed for patients with high-grade glioma, and combinations of immunotherapies and synergy with...
Immunotherapy, including therapeutic vaccines, is increasingly being developed for patients with high-grade glioma, and combinations of immunotherapies and synergy with standard of care are being investigated. In this regard, bevacizumab (BEV) has been shown to synergize with immunotherapy in preclinical studies of glioma and in other tumour entities. Here, we conducted a post-hoc exploratory study to evaluate the effect of the IMA950/poly-ICLC peptide vaccine on subsequent BEV administration in high-grade glioma patients. 16 IMA950-vaccinated and 40 non-vaccinated patients were included. At initial diagnosis, patients benefited from surgery and chemoradiation. At first or subsequent recurrence, patients received 10mg/kg of BEV every 2-3 weeks. Primary endpoints were overall survival (OS) and progression-free survival (PFS) from BEV initiation. IMA950-vaccinated patients did not show improved response to BEV as compared to non-vaccinated patients: there was no difference in median PFS (2.6 vs. 4.2 months for vaccinated and control patients, respectively, = 0.50) nor in median OS (7.8 vs. 10.0 months for vaccinated and control patients, respectively, = 0.69). In conclusion, potential synergy of BEV and therapeutic vaccines, when administered sequentially, has yet to be established in the clinical setting of GBM recurrence. Potential synergy of concomitant administration should be tested in future trials.
PubMed: 30986995
DOI: 10.3390/cancers11040464 -
Cancer Immunology, Immunotherapy : CII Jul 2018Cytotoxic T lymphocytes (CTLs) are effective components of the immune system capable of destroying tumor cells. Generation of CTLs using peptide vaccines is a practical...
Cytotoxic T lymphocytes (CTLs) are effective components of the immune system capable of destroying tumor cells. Generation of CTLs using peptide vaccines is a practical approach to treat cancer. We have previously described a peptide vaccination strategy that generates vast numbers of endogenous tumor-reactive CTLs after two sequential immunizations (prime-boost) using poly-ICLC adjuvant, which stimulates endosomal toll-like receptor 3 (TLR3) and cytoplasmic melanoma differentiation antigen 5 (MDA5). Dendritic cells (DCs) play an important role not only in antigen presentation but are critical in generating costimulatory cytokines that promote CTL expansion. Poly-ICLC was shown to be more effective than poly-IC in generating type-I interferon (IFN-I) in various DC subsets, through its enhanced ability to escape the endosomal compartment and stimulate MDA5. In our system, IFN-I did not directly function as a T cell costimulatory cytokine, but enhanced CTL expansion through the induction of IL15. With palmitoylated peptide vaccines, CD8α+ DCs were essential for peptide crosspresentation. For vaccine boosts, non-professional antigen-presenting cells were able to present minimal epitope peptides, but DCs were still required for CTL expansions through the production of IFN-I mediated by poly-ICLC. Overall, these results clarify the roles of DCs, TLR3, MDA5, IFN-I and IL15 in the generation of vast and effective antitumor CTL responses using peptide and poly-IC vaccines.
Topics: Animals; Cancer Vaccines; Carboxymethylcellulose Sodium; Dendritic Cells; Interferon Inducers; Interferon Type I; Interferon-Induced Helicase, IFIH1; Melanoma, Experimental; Mice; Mice, Inbred C57BL; Mice, Knockout; Poly I-C; Polylysine; T-Lymphocytes, Cytotoxic; Toll-Like Receptor 3; Tumor Cells, Cultured; Vaccination; Vaccines, Subunit
PubMed: 29696308
DOI: 10.1007/s00262-018-2164-6 -
EBioMedicine Jan 2016Protein-based vaccines offer a safer alternative to live-attenuated or inactivated vaccines but have limited immunogenicity. The identification of adjuvants that augment...
Protein-based vaccines offer a safer alternative to live-attenuated or inactivated vaccines but have limited immunogenicity. The identification of adjuvants that augment immunogenicity, specifically in a manner that is durable and antigen-specific, is therefore critical for advanced development. In this study, we use the filovirus virus-like particle (VLP) as a model protein-based vaccine in order to evaluate the impact of four candidate vaccine adjuvants on enhancing long term protection from Ebola virus challenge. Adjuvants tested include poly-ICLC (Hiltonol), MPLA, CpG 2395, and alhydrogel. We compared and contrasted antibody responses, neutralizing antibody responses, effector T cell responses, and T follicular helper (Tfh) cell frequencies with each adjuvant's impact on durable protection. We demonstrate that in this system, the most effective adjuvant elicits a Th1-skewed antibody response and strong CD4 T cell responses, including an increase in Tfh frequency. Using immune-deficient animals and adoptive transfer of serum and cells from vaccinated animals into naïve animals, we further demonstrate that serum and CD4 T cells play a critical role in conferring protection within effective vaccination regimens. These studies inform on the requirements of long term immune protection, which can potentially be used to guide screening of clinical-grade adjuvants for vaccine clinical development.
Topics: Adjuvants, Immunologic; Adoptive Transfer; Animals; Antibodies, Neutralizing; Antibodies, Viral; CD4-Positive T-Lymphocytes; Cytokines; Disease Models, Animal; Ebolavirus; Female; Hemorrhagic Fever, Ebola; Immunity; Immunization; Immunoglobulin G; Lymphocyte Count; Models, Animal; T-Lymphocyte Subsets; Vaccines; Vaccines, Virus-Like Particle
PubMed: 26870818
DOI: 10.1016/j.ebiom.2015.11.041 -
Nature Communications Aug 2022Both T cells and B cells have been shown to be generated after infection with SARS-CoV-2 yet protocols or experimental models to study one or the other are less common....
Both T cells and B cells have been shown to be generated after infection with SARS-CoV-2 yet protocols or experimental models to study one or the other are less common. Here, we generate a chimeric protein (SpiN) that comprises the receptor binding domain (RBD) from Spike (S) and the nucleocapsid (N) antigens from SARS-CoV-2. Memory CD4 and CD8 T cells specific for SpiN could be detected in the blood of both individuals vaccinated with Coronavac SARS-CoV-2 vaccine and COVID-19 convalescent donors. In mice, SpiN elicited a strong IFN-γ response by T cells and high levels of antibodies to the inactivated virus, but not detectable neutralizing antibodies (nAbs). Importantly, immunization of Syrian hamsters and the human Angiotensin Convertase Enzyme-2-transgenic (K18-ACE-2) mice with Poly ICLC-adjuvanted SpiN promotes robust resistance to the wild type SARS-CoV-2, as indicated by viral load, lung inflammation, clinical outcome and reduction of lethality. The protection induced by SpiN was ablated by depletion of CD4 and CD8 T cells and not transferred by antibodies from vaccinated mice. Finally, vaccination with SpiN also protects the K18-ACE-2 mice against infection with Delta and Omicron SARS-CoV-2 isolates. Hence, vaccine formulations that elicit effector T cells specific for the N and RBD proteins may be used to improve COVID-19 vaccines and potentially circumvent the immune escape by variants of concern.
Topics: Animals; Antibodies, Neutralizing; Antibodies, Viral; CD8-Positive T-Lymphocytes; COVID-19; COVID-19 Vaccines; Humans; Mice; Nucleocapsid; Nucleocapsid Proteins; SARS-CoV-2; Spike Glycoprotein, Coronavirus
PubMed: 35977933
DOI: 10.1038/s41467-022-32547-y -
JAMA Oncology Dec 2018Increasing evidence suggests the significance of the role of the immune system in the progression of smoldering multiple myeloma (SMM) to symptomatic multiple myeloma...
IMPORTANCE
Increasing evidence suggests the significance of the role of the immune system in the progression of smoldering multiple myeloma (SMM) to symptomatic multiple myeloma (MM). Boosting the immune system via vaccination in the earlier, asymptomatic SMM stage may provide a novel strategy to prevent or slow progression to active MM.
OBJECTIVE
To determine the safety, tolerability, immunogenicity, and anti-MM activity of the PVX-410 multipeptide vaccine with or without lenalidomide.
DESIGN, SETTING, AND PARTICIPANTS
This 3-cohort phase 1/2a multicenter dose-escalation study accrued 22 adults (≥18 years) with SMM with normal organ/marrow function who were human leukocyte antigen A2-positive and at moderate or high risk of progression to MM.
INTERVENTIONS
Patients received 6 doses of PVX-410 emulsified in Montanide ISA 720 VG, 0.4 mg total (0.1 mg/peptide) (n = 3) or 0.8 mg total (0.2 mg/peptide) (n = 9), biweekly via subcutaneous injection. In the combination cohort (n = 10), patients also received three 21-day cycles of lenalidomide, 25 mg, orally daily every 28 days. All patients received 0.5 mL (1 mg) poly-ICLC (2 mg/mL) via intramuscular injection with each PVX-410 dose.
MAIN OUTCOMES AND MEASURES
Adverse events (AEs) were evaluated using the Common Terminology Criteria for Adverse Events, version 4.03. PVX-410-specific T lymphocytes by flow cytometry to assess tetramer and interferon (IFN)-γ response. Disease response was assessed by investigators using the International Myeloma Working Group (IMWG) and modified European Group for Bone Marrow Transplantation (EBMT) criteria.
RESULTS
Overall, 14 (64%) patients were men and the median age at enrollment was 56 years in the monotherapy and 57 years in the combination cohorts (overall range, 39-82 years). Six of 12 patients in the monotherapy and 9 of 10 in the combination cohorts were at moderate risk. The PVX-410 vaccine was well tolerated. The most common AEs were mild-to-moderate injection site reactions and constitutional symptoms. Of note, PVX-410 was immunogenic as monotherapy (10 of 11 patients) and in combination with lenalidomide (9 of 9 patients), as demonstrated by an increase in percentage of tetramer-positive cells and IFN-γ cells in the CD3+CD8+ cell population. The combination resulted in greater mean fold increases in proportions of CD3+CD8+ T cells that were tetramer-positive and IFN-γ-positive, statistically significant for IFN-γ-positive cells after 2 and 4 vaccinations. An increase and persistence of vaccine-specific effector memory cells was noted. In total, 7 of 12 patients in the PVX-410-alone cohort had stable disease with 2 of 3 (low-dose cohort) and 1 of 9 of the target-dose cohort progressing (median TTP, 36 weeks), whereas 5 of 12 patients in the combination cohort showed, clinical response, with 1 patient progressing (median TTP not reached).
CONCLUSIONS AND RELEVANCE
Overall, these results suggest that the vaccine is safe and immunogenic in this patient population and support continued study of PVX-410 in SMM.
TRIAL REGISTRATION
ClinicalTrials.gov identifier: NCT01718899.
Topics: Adult; Aged; Aged, 80 and over; Antineoplastic Combined Chemotherapy Protocols; Cancer Vaccines; Cohort Studies; Combined Modality Therapy; Dose-Response Relationship, Drug; Female; Humans; Immunogenicity, Vaccine; Immunotherapy; Lenalidomide; Male; Middle Aged; Smoldering Multiple Myeloma; Treatment Outcome
PubMed: 30128502
DOI: 10.1001/jamaoncol.2018.3267