scholarly journals 479 A lymph-node targeted amphiphile vaccine induces potent cellular and humoral immunity to SARS-CoV-2

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A513-A513
Author(s):  
Martin Steinbuck ◽  
Peter DeMuth ◽  
Lochana Seenappa ◽  
Christopher Haqq ◽  
Aniela Jakubowski ◽  
...  
Keyword(s):  
Immune Response ◽  
T Cells ◽  
T Cell ◽  
Immune Responses ◽  
Receptor Binding ◽  
Intracellular Cytokine Staining ◽  
T Cell Responses ◽  
Humoral Immune ◽  
Cell Responses ◽  
Humoral Immune Responses

BackgroundThe SARS-CoV-2 pandemic’s public health, economic, and social impacts mandate urgent development of effective vaccines to contain or eradicate infection. To that end, we evaluated a novel amphiphile (AMP) vaccine adjuvant, AMP-CpG, composed of diacyl lipid-modified CpG, admixed with the SARS-CoV-2 Spike-2 receptor binding domain (Spike RBD) protein for immunization (ELI 005) in two mouse models. AMP immunogens are efficiently delivered to lymph nodes, where innate and adaptive immune responses are generated.MethodsFemale, 6 to 8-week-old C57BL/6J and BALB/c mice and 37-week-old C57BL/6J mice received two or more doses of benchmark (alum or CpG) or AMP-modified vaccines, comprised of Spike RBD protein and AMP-CpG adjuvant, subcutaneously injected into the tail base in two-week intervals. Antigen was dose spared to determine if AMP-CpG would maintain the immune response. Cellular immune responses were determined via ELISpot analysis of IFNγ production by splenocytes, intracellular cytokine staining of peripheral blood and lung-resident T-cells, and flowcytometric bead array analysis of Th1/2/17 cytokines. Humoral immune responses were determined via blood serum ELISAs to determine sera antibody binding titers, and pseudoviral neutralization assays for comparison to human convalescent serum.ResultsCompared to alum, AMP immunization induced 29-fold higher antigen-specific T cells which produced multiple Th1 cytokines and trafficked into lung parenchyma. Antibody responses favored Th1 isotypes (IgG2bc, IgG3) and potently neutralized Spike-2-ACE2 receptor binding, with titers >100-fold higher than the natural immune response from convalescent COVID-19 patients; responses were maintained despite 10-fold dose-reduction in Spike antigen. Both cellular and humoral immune responses were preserved in aged mice.ConclusionsELI-005 exhibits the qualities of an optimal SARS-CoV-2 vaccine, which should (1) induce robust and durable CD8+ and CD4+ T cell responses, (2) elicit high magnitude neutralizing antibodies, (3) produce Th1 bias in the elicited antibody and T cell responses, (4) potentially expand pre-existing cross-reactive T cells, (5) enable dose-sparing of required immunogens to improve the speed and cost of broad vaccination campaigns, and (6) be efficacious in elderly populations. These advantages merit clinical translation to SARS-CoV-2 and other protein subunit vaccines.

EBV-positive lymphoma patients have a selective deficiency in EBV immunity

2007 ◽  
Vol 25 (18_suppl) ◽  
pp. 21032-21032
Author(s):  
K. N. Heller ◽  
P. G. Steinherz ◽  
C. S. Portlock ◽  
C. Münz
Keyword(s):  
Immune Response ◽  
T Cells ◽  
T Cell ◽  
Immune Responses ◽  
Healthy Volunteers ◽  
Cell Response ◽  
T Cell Responses ◽  
T Cell Response ◽  
Specific Immune Response ◽  
Cell Responses

21032 Background: Epstein-Barr virus (EBV) asymptomatically establishes persistent infections in more than 90% of the adult population. However, due to effective immune control, only a minority of infected carriers develops spontaneous EBV-associated lymphomas. Since EBV nuclear antigen-1 (EBNA1) is the only protein expressed in all proliferating EBV infected cells we hypothesize that EBNA1 specific immune response is critical in preventing EBV-positive lymphomas. Methods: After informed consent, peripheral blood from healthy volunteers and lymphoma patients (prior to therapy- no evidence of cytopenia) were stimulated (ex vivo) with overlapping peptides covering the immunogenic EBNA1 (aa400–641) sequence. Frequency of EBNA1-specific T-cells were assessed by intracellular cytokine staining and flow cytometric proliferation assays. Cytokine pattern, surface marker phenotype and functional reactivity against EBV specific and control antigens were analyzed. Results: Patient and volunteer immune responses to control antigens and other viruses were assessed and statistically indistinguishable. EBNA1 specific CD4+ T cell responses were detected among 18 of 20 healthy carriers, and among 10 of 16 patients with EBV-negative lymphoma (relative to healthy volunteers p=0.145 via paired student T test). None of the patients with EBV-positive lymphomas (n=8) had a detectable EBNA1-specific CD4+ T-cell response (p<0.003 relative to healthy volunteers and patients with EBV-negative lymphomas). Conclusions: Healthy volunteers and patients with EBV-negative lymphoma have statistically similar EBNA1-specific CD4+ T cell responses. Although patients with EBV-positive lymphoma have intact immune responses to common viruses and antigens, they selectively lack an EBNA1-specific CD4+ T cell response. An intact EBNA1 specific immune response among patients with EBV-negaitve lymphoma implies that lymphoma is not a cause of a selective immune deficiency. On the contrary, these findings suggest that EBNA1-specific CD4+ T cells are critical in the prevention of EBV mediated lymphomas, and a defect in EBNA1 specific immunity may leave EBV carriers suseptible to EBV-positive lymphomas. EBNA1- specific CD4+ T cell function may be a new target for therapies of EBV-associated malignancies. No significant financial relationships to disclose.

EBV-specific immune responses in patients with multiple sclerosis responding to IFNβ therapy

2011 ◽  
Vol 18 (5) ◽  
pp. 605-609 ◽  
Author(s):  
Manuel Comabella ◽  
Kristina Kakalacheva ◽  
Jordi Río ◽  
Christian Münz ◽  
Xavier Montalban ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
T Cell ◽  
Immune Responses ◽  
T Cell Responses ◽  
Lytic Replication ◽  
Nuclear Antigen ◽  
Humoral Immune ◽  
Cell Responses ◽  
Humoral Immune Responses ◽  
Specific Igg

Background: Symptomatic primary infection with the human γ-herpesvirus Epstein–Barr virus (EBV) and elevated immune responses to EBV are associated with the development and progression of multiple sclerosis (MS). Interferon-beta (IFNβ), first-line treatment for relapse-onset MS, exhibits complex immunoregulatory and antiviral activities. Objective: To determine EBV-specific immune responses in patients with MS during IFNβ therapy. Methods: We evaluated cellular and humoral immune responses to EBV- and human cytomegalovirus (HCMV)-encoded antigens in patients with MS before and 1 year after IFNβ treatment by ELISA and flow cytometry. Twenty-eight patients with MS who showed a clinical response to IFNβ as defined by the absence of relapses and lack of progression on the Expanded Disability Status Scale score during the first 2 years of treatment were included. Results: Clinically effective IFNβ-therapy was associated with a downregulation of proliferative T cell responses to the latent EBV nuclear antigen-1 (EBNA1). EBNA1-specific IgG responses as well as cellular and humoral immune responses to MHC class I restricted EBV antigens expressed during lytic replication and viral B cell transformation were similar before and after IFNβ therapy. Although HCMV-specific IgG levels slightly decreased, proliferative T-cell responses towards HCMV antigens remained unchanged during IFNβ therapy. Conclusion: Clinically effective IFNβ therapy is associated with a reduction of proliferative T-cell responses to EBNA1.

scholarly journals Strong anti-viral responses in pediatric COVID-19 patients in South Brazil

2021 ◽  
Author(s):  
Tiago Fazolo ◽  
Karina Lima ◽  
Julia C. Fontoura ◽  
Priscila Oliveira de Souza ◽  
Gabriel Hilario ◽  
...  
Keyword(s):  
T Cell ◽  
Immune Responses ◽  
T Cell Responses ◽  
Humoral Immune ◽  
Cell Responses ◽  
Humoral Immune Responses ◽  
Hla Dr ◽  
Data Points ◽  
Viral Responses ◽  
Immune Profiling

AbstractEpidemiological evidence that COVID-19 manifests as a milder disease in children compared to adults has been reported by numerous studies, but the mechanisms underlying this phenomenon have not been characterized. It is still unclear how frequently children get infected, and/or generate immune responses to SARS-CoV-2. We have performed immune profiling of pediatric and adult COVID-19 patients in Brazil, producing over 38 thousand data points, asking if cellular or humoral immune responses could help explain milder disease in children. In this study, pediatric COVID-19 patients presented high viral titers. Though their non-specific immune profile was dominated by naive, non-activated lymphocytes, their dendritic cells expressed high levels of HLA-DR and were low in CX3CR1, indicating competence to generate immune responses that are not targeted to inflamed tissue. Finally, children formed strong specific antibody and T cell responses for viral structural proteins. Children’s T cell responses differed from adults in that their CD8+ TNFα+ T cell responses were low for S peptide but significantly higher against N and M peptide pools. Altogether, our data support a scenario in which SARS-CoV-2 infected children may contribute to transmission, though generating strong and differential responses to the virus that might associate with protection in pediatric COVID-19 presentation.

scholarly journals Strong specific anti-viral responses in pediatric COVID-19 patients in South Brazil

2021 ◽  
Author(s):  
Tiago Fazolo ◽  
Karina Lima ◽  
Julia Fontoura ◽  
Priscila de Souza ◽  
Gabriel Hilario ◽  
...  
Keyword(s):  
T Cell ◽  
Immune Responses ◽  
T Cell Responses ◽  
Humoral Immune ◽  
Cell Responses ◽  
Humoral Immune Responses ◽  
Hla Dr ◽  
Data Points ◽  
Viral Responses ◽  
Immune Profiling

Abstract Epidemiological evidence that COVID-19 manifests as a milder disease in children compared to adults has been reported by numerous studies, but the mechanisms underlying this phenomenon have not been characterized. It is still unclear how frequently children get infected, and/or generate immune responses to SARS-CoV-2. We have performed immune profiling of pediatric and adult COVID-19 patients in Brazil, producing over 38 thousand data points, asking if cellular or humoral immune responses could help explain milder disease in children. In this study, pediatric COVID-19 patients presented high viral titers. Though their non-specific immune profile was dominated by naive, non-activated lymphocytes, their dendritic cells expressed high levels of HLA-DR and were low in CX3CR1, indicating competence to generate immune responses that are not targeted to inflamed tissue. Finally, children formed strong specific antibody and T cell responses for viral structural proteins. Children’s T cell responses differed from adults in that their CD8+ TNFα+ T cell responses were low for S peptide but significantly higher against N and M peptide pools. Altogether, our data support a scenario in which SARS-CoV-2 infected children may contribute to transmission, though generating strong and differential responses to the virus that might associate with protection in pediatric COVID-19 presentation.

scholarly journals Melioidosis Patient Survival Correlates With Strong IFN-γ Secreting T Cell Responses Against Hcp1 and TssM

2021 ◽  
Vol 12 ◽  
Author(s):  
Sineenart Sengyee ◽  
Atchara Yarasai ◽  
Rachan Janon ◽  
Chumpol Morakot ◽  
Orawan Ottiwet ◽  
...  
Keyword(s):  
T Cell ◽  
Immune Responses ◽  
Clinical Manifestations ◽  
T Cell Responses ◽  
Peptide Pool ◽  
Humoral Immune ◽  
Cell Responses ◽  
Humoral Immune Responses ◽  
Healthy Donors ◽  
Ifn Γ

Melioidosis, caused by the Gram-negative bacterium Burkholderia pseudomallei, is a serious infectious disease with diverse clinical manifestations. The morbidity and mortality of melioidosis is high in Southeast Asia and no licensed vaccines currently exist. This study was aimed at evaluating human cellular and humoral immune responses in Thai adults against four melioidosis vaccine candidate antigens. Blood samples from 91 melioidosis patients and 100 healthy donors from northeast Thailand were examined for immune responses against B. pseudomallei Hcp1, AhpC, TssM and LolC using a variety of cellular and humoral immune assays including IFN-γ ELISpot assays, flow cytometry and ELISA. PHA and a CPI peptide pool were also used as control stimuli in the ELISpot assays. Hcp1 and TssM stimulated strong IFN-γ secreting T cell responses in acute melioidosis patients which correlated with survival. High IFN-γ secreting CD4+ T cell responses were observed during acute melioidosis. Interestingly, while T cell responses of melioidosis patients against the CPI peptide pool were low at the time of enrollment, the levels increased to the same as in healthy donors by day 28. Although high IgG levels against Hcp1 and AhpC were detected in acute melioidosis patients, no significant differences between survivors and non-survivors were observed. Collectively, these studies help to further our understanding of immunity against disease following natural exposure of humans to B. pseudomallei as well as provide important insights for the selection of candidate antigens for use in the development of safe and effective melioidosis subunit vaccines.

scholarly journals SARS-CoV-2 ferritin nanoparticle vaccine induces robust innate immune activity driving polyfunctional spike-specific T cell responses

npj Vaccines ◽  
2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Joshua M. Carmen ◽  
Shikha Shrivastava ◽  
Zhongyan Lu ◽  
Alexander Anderson ◽  
Elaine B. Morrison ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Cell Responses ◽  
Innate Immune ◽  
Humoral Immune ◽  
Cell Responses ◽  
Adaptive Immune ◽  
Humoral Immune Responses ◽  
Specific Memory ◽  
Antigen Presenting

AbstractThe emergence of variants of concern, some with reduced susceptibility to COVID-19 vaccines underscores consideration for the understanding of vaccine design that optimizes induction of effective cellular and humoral immune responses. We assessed a SARS-CoV-2 spike-ferritin nanoparticle (SpFN) immunogen paired with two distinct adjuvants, Alhydrogel® or Army Liposome Formulation containing QS-21 (ALFQ) for unique vaccine evoked immune signatures. Recruitment of highly activated multifaceted antigen-presenting cells to the lymph nodes of SpFN+ALFQ vaccinated mice was associated with an increased frequency of polyfunctional spike-specific memory CD4+ T cells and Kb spike-(539–546)-specific long-lived memory CD8+ T cells with effective cytolytic function and distribution to the lungs. The presence of this epitope in SARS-CoV, suggests that generation of cross-reactive T cells may be induced against other coronavirus strains. Our study reveals that a nanoparticle vaccine, combined with a potent adjuvant that effectively engages innate immune cells, enhances SARS-CoV-2-specific durable adaptive immune T cell responses.

Immune impact induced by PSA-tricom, a therapeutic vaccine for prostate cancer.

2014 ◽  
Vol 32 (4_suppl) ◽  
pp. 245-245
Author(s):  
Ravi Amrit Madan ◽  
Kwong Yok Tsang ◽  
Caroline Jochems ◽  
Jennifer L. Marte ◽  
Jo A Tucker ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Immune Response ◽  
T Cells ◽  
T Cell ◽  
Immune Responses ◽  
Specific Antigen ◽  
T Cell Responses ◽  
Fold Increase ◽  
Phase Iii ◽  
Cell Responses

245 Background: PSA-TRICOM is a vector-based therapeutic cancer vaccine designed to generate a targeted anti-tumor immune response against prostate-specific antigen (PSA)–expressing tumor cells. Early clinical trials have evaluated the immunologic impact of this vaccine and demonstrated promising clinical activity. PSA-TRICOM is being evaluated in a phase III trial in metastatic castration resistant prostate cancer (mCRPC). Methods: We recently conducted a broad overview of both published and new data which analyzed the immune responses to PSA-TRICOM. Immune responses included ELISPOT for antigen-specific immune response and flow-cytometry analysis of peripheral immune cells. Results: 104 patients (pts) with prostate cancer were tested for T-cell responses and 59 out of 104 (57%) demonstrated a greater than or equal to 2-fold increase in PSA-specific T cells 4 weeks after vaccine. The responders had a median 5-fold increase relative to pre-vaccine levels. For most pts PSA-specific immune responses (likely memory cells) seen 28 days following the most recent vaccine are quantitatively similar to levels of circulating influenza-specific T cells in the same pts. In addition, 19 out of 28 pts (68%) evaluated demonstrated immune responses to tumor-associated antigens not present in the vaccine (antigen spreading). Since PSA-TRICOM is designed to generate a cellular (TH1 immune response), it is not surprising that 2 out of 349 pts (<1.0%) demonstrated evidence of PSA antibody induction following vaccine. This suggests that post-vaccine PSA kinetics were not affected by PSA antibodies. Conclusions: PSA-TRICOM has demonstrated the ability to generate immune responses. Despite these findings, it is important to note that systemic immune response to PSA may underestimate the true therapeutic immune response since it does not measure cells that trafficked to tumor or antigen spreading. Furthermore, while the entire PSA gene is the vaccine, only one epitope of PSA is specifically evaluated in the T-cell responses. Further immune analysis continues in an ongoing phase III of PSA-TRICOM in mCRPC (NCT01322490), accruing worldwide, and two trials combining PSA-TRICOM with enzalutamide (biochemical recurrence/ NCT01875250 and mCRPC/ NCT01867333) currently accruing at NCI. Clinical trial information: multiple trials.

scholarly journals 413 GEN-009, a personalized neoantigen vaccine, elicits robust immune responses in individuals with advanced or metastatic solid tumors

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A438-A438
Author(s):  
Mara Shainheit ◽  
Devin Champagne ◽  
Gabriella Santone ◽  
Syukri Shukor ◽  
Ece Bicak ◽  
...  
Keyword(s):  
Clinical Trial ◽  
T Cells ◽  
T Cell ◽  
Immune Responses ◽  
Solid Tumors ◽  
Ex Vivo ◽  
T Cell Responses ◽  
Checkpoint Blockade ◽  
T Cell Subsets ◽  
Cell Responses

BackgroundATLASTM is a cell-based bioassay that utilizes a cancer patient‘s own monocyte-derived dendritic cells and CD4+ and CD8+ T cells to screen their mutanome and identify neoantigens that elicit robust anti-tumor T cell responses, as well as, deleterious InhibigensTM.1 GEN-009, a personalized vaccine comprised of 4–20 ATLAS-identified neoantigens combined with Hiltonol®, harnesses the power of neoantigen-specific T cells to treat individuals with solid tumors. The safety and efficacy of GEN-009 is being assessed in a phase 1/2a clinical trial (NCT03633110).MethodsA cohort of 15 adults with solid tumors were enrolled in the study. During the screening period, patients received standard of care PD-1-based immunotherapies appropriate for their tumor type. Subsequently, patients were immunized with GEN-009 with additional doses administered at 3, 6, 12, and 24 weeks. Peripheral blood mononuclear cells (PBMCs) were collected at baseline, pre-vaccination (D1), as well as 29, 50, 92, and 176 days post first dose. Vaccine-induced immunogenicity and persistence were assessed by quantifying neoantigen-specific T cell responses in ex vivo and in vitro stimulation dual-analyte fluorospot assays. Polyfunctionality of neoantigen-specific T cells was evaluated by intracellular cytokine staining. Additionally, potential correlations between the ATLAS-identified profile and vaccine-induced immunogenicity were assessed.ResultsGEN-009 augmented T cell responses in 100% of evaluated patients, attributable to vaccine and not checkpoint blockade. Furthermore, neoantigen-induced secretion of IFNγ and/or TNFα by PBMCs, CD4+, and CD8+ T cells was observed in all patients. Responses were primarily from polyfunctional TEM cells and detectable in both CD4+ and CD8+ T cell subsets. Some patients had evidence of epitope spreading. Unique response patterns were observed for each patient with no apparent relationship between tumor types and time to emergence, magnitude or persistence of response. Ex vivo vaccine-induced immune responses were observed as early as 1 month, and in some cases, persisted for 176 days. Clinical efficacy possibly attributable to GEN-009 was observed in several patients, but no correlation has yet been identified with neoantigen number or magnitude of immune response.ConclusionsATLAS empirically identifies stimulatory neoantigens using the patient‘s own immune cells. GEN-009, which is comprised of personalized, ATLAS-identified neoantigens, elicits early, long-lasting and polyfunctional neoantigen-specific CD4+ and CD8+ T cell responses in individuals with advanced cancer. Several patients achieved clinical responses that were possibly attributable to vaccine; efforts are underway to explore T cell correlates of protection. These data support that GEN-009, in combination with checkpoint blockade, represents a unique approach to treat solid tumors.AcknowledgementsWe are grateful to the patients and their families who consented to participate in the GEN-009-101 clinical trial.Trial RegistrationNCT03633110Ethics ApprovalThis study was approved by Western Institutional Review Board, approval number 1-1078861-1. All subjects contributing samples provided signed individual informed consent.ReferenceDeVault V, Starobinets H, Adhikari S, Singh S, Rinaldi S, Classon B, Flechtner J, Lam H. Inhibigens, personal neoantigens that drive suppressive T cell responses, abrogate protection of therapeutic anti-tumor vaccines. J. Immunol 2020; 204(1 Supplement):91.15.

scholarly journals Detection of IFNγ-Secreting CD4+ and CD8+ Memory T Cells in COVID-19 Convalescents after Stimulation of Peripheral Blood Mononuclear Cells with Live SARS-CoV-2

Viruses ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1490
Author(s):  
Victoria Matyushenko ◽  
Irina Isakova-Sivak ◽  
Igor Kudryavtsev ◽  
Arina Goshina ◽  
Anna Chistyakova ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Memory T Cells ◽  
Natural Infection ◽  
Intracellular Cytokine Staining ◽  
T Cell Responses ◽  
Effector Memory ◽  
Memory T Cell ◽  
Cell Responses ◽  
Stimulation Of

Background: New coronavirus SARS-CoV-2, a causative agent of the COVID-19 pandemic, has been circulating among humans since November 2019. Multiple studies have assessed the qualitative and quantitative characteristics of virus-specific immunity in COVID-19 convalescents, however, some aspects of the development of memory T-cell responses after natural SARS-CoV-2 infection remain uncovered. Methods: In most of published studies T-cell immunity to the new coronavirus is assessed using peptides corresponding to SARS-CoV-1 or SARS-CoV-2 T-cell epitopes, or with peptide pools covering various parts of the viral proteins. Here, we determined the level of CD4+ and CD8+ memory T-cell responses in COVID-19 convalescents by stimulating PBMCs collected 1 to 6 months after recovery with sucrose gradient-purified live SARS-CoV-2. IFNγ production by the central and effector memory helper and cytotoxic T cells was assessed by intracellular cytokine staining assay and flow cytometry. Results: Stimulation of PBMCs with live SARS-CoV-2 revealed IFNγ-producing T-helper effector memory cells with CD4+CD45RA−CCR7− phenotype, which persisted in circulation for up to 6 month after COVID-19. In contrast, SARS-CoV-2-specific IFNγ-secreting cytotoxic effector memory T cells were found at significant levels only shortly after the disease, but rapidly decreased over time. Conclusion: The stimulation of immune cells with live SARS-CoV-2 revealed a rapid decline in the pool of effector memory CD8+, but not CD4+, T cells after recovery from COVID-19. These data provide additional information on the development and persistence of cellular immune responses after natural infection, and can inform further development of T cell-based SARS-CoV-2 vaccines.

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