scholarly journals Quantification of dengue virus specific T cell responses and correlation with viral load and clinical disease severity in acute dengue infection

2018 ◽  
Author(s):  
Dulharie T. Wijeratne ◽  
Samitha Fernando ◽  
Laksiri Gomes ◽  
Chandima Jeewandara ◽  
Anushka Ginneliya ◽  
...  
Keyword(s):  
T Cell ◽  
Dengue Virus ◽  
Disease Severity ◽  
Ex Vivo ◽  
Dengue Infection ◽  
T Cell Responses ◽  
Clinical Disease ◽  
Cell Responses ◽  
Early Appearance ◽  
Liver Transaminases

AbstractBackgroundIn order to understand the role of dengue virus (DENV) specific T cell responses that associate with protection, we studied their frequency and phenotype in relation to clinical disease severity and resolution of viraemia in a large cohort of patients with varying severity of acute dengue infection.Methodology/Principal findingsUsing ex vivo IFNγ ELISpot assays we determined the frequency of dengue viral peptide (DENV)-NS3, NS1 and NS5 responsive T cells in 74 adult patients with acute dengue infection and examined the association of responsive T cell frequency with the extent of viraemia and clinical disease severity. We found that total DENV-specific and DENV-NS3-specific T cell responses, were higher in patients with dengue fever (DF), when compared to those with dengue haemorrhagic fever (DHF). In addition, early appearance of DENV-specific T cell responses was significantly associated with milder clinical disease (p=0.02). DENV peptide specific T cell responses inversely correlated with the degree of viraemia, which was most significant for DENV-NS3 specific T cell responses (Spearman’s r = −0.47, p=0.0003). The frequency of T cell responses to NS1, NS5 and pooled DENV peptides, correlated with the degree of thrombocytopenia but had no association with levels of liver transaminases. In contrast, DENV-IgG inversely correlated with the degree of thrombocytopenia and levels of liver transaminases.Conclusions/significanceEarly appearance of DENV-specific T cell IFNγ responses appears to associate with milder clinical disease and resolution of viraemia, suggesting a protective role in acute dengue infection.

scholarly journals Association of dengue virus‐specific polyfunctional T‐cell responses with clinical disease severity in acute dengue infection

2019 ◽  
Vol 7 (4) ◽  
pp. 276-285 ◽  
Author(s):  
Dulharie T. Wijeratne ◽  
Samitha Fernando ◽  
Laksiri Gomes ◽  
Chandima Jeewandara ◽  
Geethal Jayarathna ◽  
...  
Keyword(s):  
T Cell ◽  
Dengue Virus ◽  
Disease Severity ◽  
Dengue Infection ◽  
T Cell Responses ◽  
Clinical Disease ◽  
Cell Responses

scholarly journals Quantification of dengue virus specific T cell responses and correlation with viral load and clinical disease severity in acute dengue infection

2018 ◽  
Vol 12 (10) ◽  
pp. e0006540 ◽  
Author(s):  
Dulharie T. Wijeratne ◽  
Samitha Fernando ◽  
Laksiri Gomes ◽  
Chandima Jeewandara ◽  
Anushka Ginneliya ◽  
...  
Keyword(s):  
Viral Load ◽  
T Cell ◽  
Dengue Virus ◽  
Disease Severity ◽  
Dengue Infection ◽  
T Cell Responses ◽  
Clinical Disease ◽  
Cell Responses

scholarly journals Dengue virus infection elicits highly polarized CX3CR1+cytotoxic CD4+T cells associated with protective immunity

2015 ◽  
Vol 112 (31) ◽  
pp. E4256-E4263 ◽  
Author(s):  
Daniela Weiskopf ◽  
Derek J. Bangs ◽  
John Sidney ◽  
Ravi V. Kolla ◽  
Aruna D. De Silva ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Dengue Virus ◽  
Ex Vivo ◽  
Natural Infection ◽  
Dengue Infection ◽  
Flow Cytometric Analysis ◽  
T Cell Responses ◽  
Severe Dengue ◽  
Cell Responses

Dengue virus (DENV) is a rapidly spreading pathogen with unusual pathogenesis, and correlates of protection from severe dengue disease and vaccine efficacy have not yet been established. Although DENV-specific CD8+T-cell responses have been extensively studied, the breadth and specificity of CD4+T-cell responses remains to be defined. Here we define HLA-restricted CD4+T-cell epitopes resulting from natural infection with dengue virus in a hyperepidemic setting. Ex vivo flow-cytometric analysis of DENV-specific CD4+T cells revealed that the virus-specific cells were highly polarized, with a strong bias toward a CX3CR1+Eomesodermin+perforin+granzyme B+CD45RA+CD4 CTL phenotype. Importantly, these cells correlated with a protective HLA DR allele, and we demonstrate that these cells have direct ex vivo DENV-specific cytolytic activity. We speculate that cytotoxic dengue-specific CD4+T cells may play a role in the control of dengue infection in vivo, and this immune correlate may be a key target for dengue virus vaccine development.

scholarly journals Functionality of Dengue Virus Specific Memory T Cell Responses in Individuals Who Were Hospitalized or Who Had Mild or Subclinical Dengue Infection

2015 ◽  
Vol 9 (4) ◽  
pp. e0003673 ◽  
Author(s):  
Chandima Jeewandara ◽  
Thiruni N. Adikari ◽  
Laksiri Gomes ◽  
Samitha Fernando ◽  
R. H. Fernando ◽  
...  
Keyword(s):  
T Cell ◽  
Dengue Virus ◽  
Dengue Infection ◽  
T Cell Responses ◽  
Memory T Cell ◽  
Cell Responses ◽  
Specific Memory

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 Characterisation of CD154+ T cells following ex vivo allergen stimulation illustrates distinct T cell responses to seasonal and perennial allergens in allergic and non-allergic individuals

2013 ◽  
Vol 14 (1) ◽  
pp. 49 ◽  
Author(s):  
Karen A Smith ◽  
Nicola J Gray ◽  
Femi Saleh ◽  
Elizabeth Cheek ◽  
Anthony J Frew ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Ex Vivo ◽  
T Cell Responses ◽  
Cell Responses ◽  
Perennial Allergens

scholarly journals 153 NEO-PTC-01 (BNT-221), an autologous neoantigen-specific T-cell product for adoptive cell therapy of metastatic melanoma

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A167-A167
Author(s):  
Divya Lenkala ◽  
Jessica Kohler ◽  
Brian McCarthy ◽  
Michael Nelson ◽  
Jonathan McGee ◽  
...  
Keyword(s):  
T Cell ◽  
Metastatic Melanoma ◽  
Ex Vivo ◽  
Adoptive Cell Therapy ◽  
T Cell Responses ◽  
Process Engineering ◽  
High Quality ◽  
Cell Product ◽  
Cell Responses ◽  
Melanoma Patients

BackgroundNeoantigens are tumor-specific antigens that are important in the anti-tumor immune response. These antigens are not subject to central immune tolerance and are therefore potentially more immunogenic than tumor-associated antigens. NEO-STIM®, our propriety ex vivo induction process, was developed to generate T-cell products specific to these neoantigens from the peripheral blood of patient. Here, we present the results of a proof of concept, pre-clinical study with multiple successful process engineering runs generating a neoantigen-specific T-cell product (NEO-PTC-01) using leukaphereses from metastatic melanoma patients. These products contain specific T-cell responses targeting multiple neoantigens from each individual patient‘s tumor.MethodsPatient-specific neoantigens were predicted using our RECON® bioinformatics platform. Predicted high-quality neoantigens were utilized in our ex vivo stimulation protocol, NEO-STIM, in the process engineering runs of NEO-PTC-01. NEO-STIM is used to prime, activate and expand memory and de novo T-cell responses from both the CD4+ and the CD8+ compartment. High throughput flow cytometric analysis was performed to characterize the specificity and functionality (cytokine production and cytolytic capacity) of the induced T-cell responses.ResultsHere we present the successful induction of 4–5 CD8+ and 4–7 CD4+ T-cell responses per patient, generated using peripheral blood mononuclear cells from multiple melanoma patients during these successful process engineering runs. We then extensively characterized these T-cell responses and demonstrate that these responses are functional, specific and have cytolytic capacity. Moreover, the induced T cells can recognize autologous tumor.ConclusionsNEO-STIM is a novel platform that generates ex vivo T-cell responses to high-quality neoantigen targets. NEO-PTC-01, the neoantigen-specific T cell product generated from this process, is a potent adoptive cell therapy targeting multiple immunogenic neoantigens in patients with metastatic melanoma.

scholarly journals Analysis of CD4+ T-Cell Responses to Human Papillomavirus (HPV) Type 11 L1 in Healthy Adults Reveals a High Degree of Responsiveness and Cross-Reactivity with Other HPV Types

2002 ◽  
Vol 76 (15) ◽  
pp. 7418-7429 ◽  
Author(s):  
O. Martin Williams ◽  
Keith W. Hart ◽  
Eddie C. Y. Wang ◽  
Colin M. Gelder
Keyword(s):  
Human Papillomavirus ◽  
T Cell ◽  
In Vitro Selection ◽  
Mononuclear Cells ◽  
Ex Vivo ◽  
T Cell Responses ◽  
Cross Reactivity ◽  
Peripheral Blood Mononuclear ◽  
Cell Responses ◽  
Hpv Types

ABSTRACT Human papillomavirus type 11 (HPV-11) infection causes genital warts and recurrent respiratory papillomatosis. While there is compelling evidence that CD4+ T cells play an important role in immune surveillance of HPV-associated diseases, little is known about human CD4+ T-cell recognition of HPV-11. We have investigated the CD4+ T-cell responses of 25 unrelated healthy donors to HPV-11 L1 virus-like particles (VLP). CD4+ T-cell lines from 21 of 25 donors were established. Cell sorting experiments carried out on cells from six donors demonstrated that the response was located in the CD45RAlow CD45ROhigh memory T-cell population. To determine the peptide specificity of these responses, epitope selection was analyzed by using 95 15-mer peptides spanning the entire HPV-11 L1 protein. No single region of L1 was immunodominant; responders recognized between 1 and 10 peptides, located throughout the protein, and peptide responses fell into clear HLA class II restricted patterns. Panels of L1 peptides specific for skin and genital HPV were used to show that the L1 CD4+ T-cell responses were cross-reactive. The degree of cross-reactivity was inversely related to the degree of L1 sequence diversity between these viruses. Finally, responses to HPV-11 L1 peptides were elicited from ex vivo CD45RO+ peripheral blood mononuclear cells, demonstrating that recognition of HPV-11 was a specific memory response and not due to in vitro selection during tissue culture. This is the first study of CD4+ T-cell responses to HPV-11 in healthy subjects and demonstrates marked cross-reactivity with other skin and genital HPV types. This cross-reactivity may be of significance for vaccine strategies against HPV-associated clinical diseases.

scholarly journals Novel Recombinant Mycobacterium bovis BCG, Ovine Atadenovirus, and Modified Vaccinia Virus Ankara Vaccines Combine To Induce Robust Human Immunodeficiency Virus-Specific CD4 and CD8 T-Cell Responses in Rhesus Macaques

2010 ◽  
Vol 84 (12) ◽  
pp. 5898-5908 ◽  
Author(s):  
Maximillian Rosario ◽  
Richard Hopkins ◽  
John Fulkerson ◽  
Nicola Borthwick ◽  
Máire F. Quigley ◽  
...  
Keyword(s):  
T Cell ◽  
Vaccinia Virus ◽  
Mycobacterium Bovis ◽  
Ex Vivo ◽  
Rhesus Macaques ◽  
T Cell Responses ◽  
Cd8 T Cell ◽  
Cell Responses ◽  
Modified Vaccinia Virus Ankara ◽  
Hiv 1

ABSTRACT Mycobacterium bovis bacillus Calmette-Guérin (BCG), which elicits a degree of protective immunity against tuberculosis, is the most widely used vaccine in the world. Due to its persistence and immunogenicity, BCG has been proposed as a vector for vaccines against other infections, including HIV-1. BCG has a very good safety record, although it can cause disseminated disease in immunocompromised individuals. Here, we constructed a recombinant BCG vector expressing HIV-1 clade A-derived immunogen HIVA using the recently described safer and more immunogenic BCG strain AERAS-401 as the parental mycobacterium. Using routine ex vivo T-cell assays, BCG.HIVA401 as a stand-alone vaccine induced undetectable and weak CD8 T-cell responses in BALB/c mice and rhesus macaques, respectively. However, when BCG.HIVA401 was used as a priming component in heterologous vaccination regimens together with recombinant modified vaccinia virus Ankara-vectored MVA.HIVA and ovine atadenovirus-vectored OAdV.HIVA vaccines, robust HIV-1-specific T-cell responses were elicited. These high-frequency T-cell responses were broadly directed and capable of proliferation in response to recall antigen. Furthermore, multiple antigen-specific T-cell clonotypes were efficiently recruited into the memory pool. These desirable features are thought to be associated with good control of HIV-1 infection. In addition, strong and persistent T-cell responses specific for the BCG-derived purified protein derivative (PPD) antigen were induced. This work is the first demonstration of immunogenicity for two novel vaccine vectors and the corresponding candidate HIV-1 vaccines BCG.HIVA401 and OAdV.HIVA in nonhuman primates. These results strongly support their further exploration.

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