scholarly journals Development of combination adjuvant for efficient T cell and antibody response induction against protein antigen

PLoS ONE ◽  
2021 ◽  
Vol 16 (8) ◽  
pp. e0254628
Author(s):  
Yasunari Haseda ◽  
Lisa Munakata ◽  
Chiyo Kimura ◽  
Yumi Kinugasa-Katayama ◽  
Yasuko Mori ◽  
...  
Keyword(s):  
T Cell ◽  
Neutralizing Antibodies ◽  
Aluminum Salt ◽  
Protein Antigen ◽  
New Combination ◽  
Vaccine Adjuvants ◽  
Protein Antigens ◽  
Antigen Uptake

Most current clinical vaccines work primarily by inducing the production of neutralizing antibodies against pathogens. Vaccine adjuvants that efficiently induce T cell responses to protein antigens need to be developed. In this study, we developed a new combination adjuvant consisting of 1,2-dioleoyl-3-trimethylammonium propane (DOTAP), D35, and an aluminum salt. Among the various combinations tested, the DOTAP/D35/aluminum salt adjuvant induced strong T cell and antibody responses against the model protein antigen with a single immunization. Adjuvant component and model antigen interaction studies in vitro also revealed that the strong mutual interactions among protein antigens and other components were one of the important factors for this efficient immune induction by the novel combination adjuvant. In addition, in vivo imaging of the antigen distribution suggested that the DOTAP component in the combination adjuvant formulation elicited transient antigen accumulation at the draining lymph nodes, possibly by antigen uptake DC migration. These results indicate the potential of the new combination adjuvant as a promising vaccine adjuvant candidate to treat infectious diseases and cancers.

scholarly journals Optimized Adenovirus-Antibody Complexes Stimulate Strong Cellular and Humoral Immune Responses against an Encoded Antigen in Naïve Mice and Those with Preexisting Immunity

2011 ◽  
Vol 19 (1) ◽  
pp. 84-95 ◽  
Author(s):  
Jin Huk Choi ◽  
Joe Dekker ◽  
Stephen C. Schafer ◽  
Jobby John ◽  
Craig E. Whitfill ◽  
...  
Keyword(s):  
Immune Response ◽  
T Cell ◽  
Immune Responses ◽  
Neutralizing Antibodies ◽  
T Cell Responses ◽  
Transduction Efficiency ◽  
Virus Antibody ◽  
Cell Responses

ABSTRACTThe immune response to recombinant adenoviruses is the most significant impediment to their clinical use for immunization. We test the hypothesis that specific virus-antibody combinations dictate the type of immune response generated against the adenovirus and its transgene cassette under certain physiological conditions while minimizing vector-induced toxicity.In vitroandin vivoassays were used to characterize the transduction efficiency, the T and B cell responses to the encoded transgene, and the toxicity of 1 × 1011adenovirus particles mixed with different concentrations of neutralizing antibodies. Complexes formed at concentrations of 500 to 0.05 times the 50% neutralizing dose (ND50) elicited strong virus- and transgene-specific T cell responses. The 0.05-ND50formulation elicited measurable anti-transgene antibodies that were similar to those of virus alone (P= 0.07). This preparation also elicited very strong transgene-specific memory T cell responses (28.6 ± 5.2% proliferation versus 7.7 ± 1.4% for virus alone). Preexisting immunity significantly reduced all responses elicited by these formulations. Although lower concentrations (0.005 and 0.0005 ND50) of antibody did not improve cellular and humoral responses in naïve animals, they did promote strong cellular (0.005 ND50) and humoral (0.0005 ND50) responses in mice with preexisting immunity. Some virus-antibody complexes may improve the potency of adenovirus-based vaccines in naïve individuals, while others can sway the immune response in those with preexisting immunity. Additional studies with these and other virus-antibody ratios may be useful to predict and model the type of immune responses generated against a transgene in those with different levels of exposure to adenovirus.

scholarly journals Pore-forming alpha-hemolysin efficiently improves the immunogenicity and protective efficacy of protein antigens

2021 ◽  
Vol 17 (7) ◽  
pp. e1009752
Author(s):  
Jin-Tao Zou ◽  
Hai-Ming Jing ◽  
Yue Yuan ◽  
Lang-Huan Lei ◽  
Zhi-Fu Chen ◽  
...  
Keyword(s):  
Protective Efficacy ◽  
Antigen Delivery ◽  
Protein Antigens ◽  
Antigen Uptake ◽  
Alpha Hemolysin ◽  
Antibody Titers ◽  
Candidate Antigen ◽  
Draining Lymph Nodes

Highly immunogenic exotoxins are used as carrier proteins because they efficiently improve the immunogenicity of polysaccharides. However, their efficiency with protein antigens remains unclear. In the current study, the candidate antigen PA0833 from Pseudomonas aeruginosa was fused to the α-hemolysin mutant HlaH35A from Staphylococcus aureus to form a HlaH35A-PA0833 fusion protein (HPF). Immunization with HPF resulted in increased PA0833-specific antibody titers, higher protective efficacy, and decreased bacterial burden and pro-inflammatory cytokine secretion compared with PA0833 immunization alone. Using fluorescently labeled antigens to track antigen uptake and delivery, we found that HlaH35A fusion significantly improved antigen uptake in injected muscles and antigen delivery to draining lymph nodes. Both in vivo and in vitro studies demonstrated that the increased antigen uptake after immunization with HPF was mainly due to monocyte- and macrophage-dependent macropinocytosis, which was probably the result of HPF binding to ADAM10, the Hla host receptor. Furthermore, a transcriptome analysis showed that several immune signaling pathways were activated by HPF, shedding light on the mechanism whereby HlaH35A fusion improves immunogenicity. Finally, the improvement in immunogenicity by HlaH35A fusion was also confirmed with two other antigens, GlnH from Klebsiella pneumoniae and the model antigen OVA, indicating that HlaH35A could serve as a universal carrier protein to improve the immunogenicity of protein antigens.

scholarly journals Towards Identification of the Mechanisms of Action of Parasite-Derived Peptide GK1 on the Immunogenicity of an Influenza Vaccine

2009 ◽  
Vol 16 (9) ◽  
pp. 1338-1343 ◽  
Author(s):  
René Segura-Velázquez ◽  
Gladis Fragoso ◽  
Edda Sciutto ◽  
Adelaida Sarukhan
Keyword(s):  
Dendritic Cells ◽  
T Cell ◽  
Influenza Vaccine ◽  
T Cell Activation ◽  
Cell Activation ◽  
Mechanisms Of Action ◽  
The Body ◽  
Vaccine Adjuvants

ABSTRACT Previous studies have shown that the synthetic peptide GK1, derived from Taenia crassiceps cysticerci, enhances the immunogenicity of the commercial inactivated influenza vaccine Fluzone in both young and aged mice. In particular, antibody responses were much improved. Since GK1 is a peptide and is rapidly cleared from the body, it offers the possibility to improve vaccine performance without undesirable effects. This study was therefore designed to understand the mechanisms of action involved in the adjuvant properties of GK1. For this, transgenic mice expressing a T-cell receptor specific for an epitope from the influenza virus hemagglutinin (HA) protein were employed. The GK1 peptide significantly increased the in vivo proliferative response of HA-specific CD4+ T cells when it was coimmunized with the HA epitope. Dendritic cells treated in vitro with GK1 were capable of enhancing T-cell activation. Furthermore, in synergy with lipopolysaccharide, GK1 enhanced the expression of major histocompatibility complex class II and costimulatory molecules of dendritic cells and promoted the secretion of proinflammatory cytokines and chemokines upon antigen-driven T-cell interaction. These data provide important insights into the mechanism that underlies the GK1 adjuvant capacity observed previously and underline the feasibility of using the transgenic mouse model described herein as a tool for investigation of the modes of action of different influenza vaccine adjuvants.

567 MDK1319/MDK-701: A potent fully efficacious peptidyl agonist of IL-7Rαγc, designed with no reference to cytokine or receptor structure and unrelated to IL-7, fused to an Fc-domain for PK enhancement

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A601-A601
Author(s):  
William Dower ◽  
Alice Bakker ◽  
Steven Cwirla ◽  
Prarthana Joshi ◽  
Praechompoo Pongtornpipat ◽  
...  
Keyword(s):  
T Cell ◽  
Neutralizing Antibodies ◽  
Human Lymphocytes ◽  
Receptor Activation ◽  
Biological Properties ◽  
Cross Reactivity ◽  
Lymphocyte Subpopulation ◽  
Minimal Risk

BackgroundIL-7 receptor activation is essential for the proper development and homeostasis of T-cell subpopulations, and maintenance of the TCR clonal repertoire. Emerging evidence indicates potential clinical utility of IL-7 for immunotherapy of lymphopenia, oncology, and other indications. Here we report the discovery of MDK1319, a small novel peptidyl agonist of IL-7R. This peptide is structurally unrelated to IL-7, with a MW less than 5000D. To improve in vivo properties, we fused MDK1319 to an IgG-Fc-domain to construct MDK-701, which exhibits biological properties similar to those of IL-7 in vitro, and when administered to non-human primates.MethodsPeptides were selected from peptide libraries by screens designed to identify molecules binding simultaneously to the Rα and γc subunits of the human IL-7 receptor. Synthetic peptides, and peptides fused to IgG Fc-domains were evaluated for efficacy, potency, and quality of signaling in IL-7-responsive cell lines and human lymphocytes. PK/PD properties in non-human primates were also determined.ResultsMDK1319 and MDK-701 activate the major IL-7R signaling pathways, JAK-STAT (pSTAT5), and PI3K (pAKT), and induce proliferation in human PBMCs, exhibiting lymphocyte subpopulation selectivity, kinetics, efficacy, and potency similar to those of IL-7. Agonism is attributable to direct activation of IL-7R, as shown by dependence on the presence of the IL-7Rα subunit for response in test cells, and insensitivity to IL-7 neutralizing antibodies. MDK1319 and MDK-701 do not activate nor inhibit any other (off target) Rγc family receptors at concentrations 100-fold greater than required for maximal IL-7R activation. MDK-701 administered to cynomologous macaques (single dose, IV at 1 mg/kg) exhibits a circulating terminal half life of ~32 hr; and induces peripheral lymphocyte profiles similar to IL-7 treatment, including initial reduction (tissue migration), followed by sustained elevation of peripheral lymphocytes remaining above baseline for 29 days, with no observed adverse effects.ConclusionsIn addition to the utility of Fc-fusion MDK-701 for monotherapy, the small peptidyl nature of the active peptide MDK1319, fusable to recombinant protein partners, offers opportunities for incorporation into bispecific molecules, linking IL-7 activity to a variety of useful functions. These include synergistic cytokine activities, checkpoint blockade, and tissue targeting. Cells engineered to secrete MDK1319 display autocrine stimulation potentially useful in T-cell therapeutics. The structural novelty of MDK1319 substantially decreases risk of cross reactivity of any anti-drug immune response with endogenous IL-7, and may provide a safer alternative to modified forms of IL-7 reported to produce significant anti-IL-7 immunogenicity.Ethics ApprovalAnimal studies were performed by Envol Biomedical or Charles Rivers Laboratories, as approved by the Institution Ethics Boards with the following study and approval numbers:Envol Biomedical 7037-20 MDK2002; 7037-20: PK/PD Cynomolgus monkeysCharles Rivers Laboratories 20200121001K; US19001: PK Mouse The use of human PBMC in this study was authorized under Minimal Risk Research Related Activities at Stanford Blood Center (SQL 79075)

scholarly journals Sialic acid-modified antigens impose tolerance via inhibition of T-cell proliferation and de novo induction of regulatory T cells

2016 ◽  
Vol 113 (12) ◽  
pp. 3329-3334 ◽  
Author(s):  
Maurizio Perdicchio ◽  
Juan M. Ilarregui ◽  
Marleen I. Verstege ◽  
Lenneke A. M. Cornelissen ◽  
Sjoerd T. T. Schetters ◽  
...  
Keyword(s):  
T Cells ◽  
Sialic Acid ◽  
T Cell ◽  
De Novo ◽  
Ex Vivo ◽  
Treg Cells ◽  
Sialic Acids ◽  
Antigen Uptake

Sialic acids are negatively charged nine-carbon carboxylated monosaccharides that often cap glycans on glycosylated proteins and lipids. Because of their strategic location at the cell surface, sialic acids contribute to interactions that are critical for immune homeostasis via interactions with sialic acid-binding Ig-type lectins (siglecs). In particular, these interactions may be of importance in cases where sialic acids may be overexpressed, such as on certain pathogens and tumors. We now demonstrate that modification of antigens with sialic acids (Sia-antigens) regulates the generation of antigen-specific regulatory T (Treg) cells via dendritic cells (DCs). Additionally, DCs that take up Sia-antigen prevent formation of effector CD4+ and CD8+ T cells. Importantly, the regulatory properties endowed on DCs upon Sia-antigen uptake are antigen-specific: only T cells responsive to the sialylated antigen become tolerized. In vivo, injection of Sia-antigen–loaded DCs increased de novo Treg-cell numbers and dampened effector T-cell expansion and IFN-γ production. The dual tolerogenic features that Sia-antigen imposed on DCs are Siglec-E–mediated and maintained under inflammatory conditions. Moreover, loading DCs with Sia-antigens not only inhibited the function of in vitro–established Th1 and Th17 effector T cells but also significantly dampened ex vivo myelin-reactive T cells, present in the circulation of mice with experimental autoimmune encephalomyelitis. These data indicate that sialic acid-modified antigens instruct DCs in an antigen-specific tolerogenic programming, enhancing Treg cells and reducing the generation and propagation of inflammatory T cells. Our data suggest that sialylation of antigens provides an attractive way to induce antigen-specific immune tolerance.

scholarly journals HIV-1-Based Virus-like Particles that Morphologically Resemble Mature, Infectious HIV-1 Virions

Viruses ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 507 ◽  
Author(s):  
Christopher A. Gonelli ◽  
Georges Khoury ◽  
Rob J. Center ◽  
Damian F.J. Purcell
Keyword(s):  
T Cell ◽  
Dna Vaccine ◽  
Neutralizing Antibodies ◽  
T Cell Responses ◽  
Expression Vectors ◽  
Virus Like Particles ◽  
Cell Responses ◽  
Hiv 1

A prophylactic vaccine eliciting both broad neutralizing antibodies (bNAbs) to the HIV-1 envelope glycoprotein (Env) and strong T cell responses would be optimal for preventing HIV-1 transmissions. Replication incompetent HIV-1 virus-like particles (VLPs) offer the opportunity to present authentic-structured, virion-associated Env to elicit bNAbs, and also stimulate T cell responses. Here, we optimize our DNA vaccine plasmids as VLP expression vectors for efficient Env incorporation and budding. The original vector that was used in human trials inefficiently produced VLPs, but maximized safety by inactivating RNA genome packaging, enzyme functions that are required for integration into the host genome, and deleting accessory proteins Vif, Vpr, and Nef. These original DNA vaccine vectors generated VLPs with incomplete protease-mediated cleavage of Gag and were irregularly sized. Mutations to restore function within the defective genes revealed that several of the reverse transcriptase (RT) deletions mediated this immature phenotype. Here, we made efficient budding, protease-processed, and mature-form VLPs that resembled infectious virions by introducing alternative mutations that completely removed the RT domain, but preserved most other safety mutations. These VLPs, either expressed from DNA vectors in vivo or purified after expression in vitro, are potentially useful immunogens that can be used to elicit antibody responses that target Env on fully infectious HIV-1 virions.

Interleukin-21 inhibits dendritic cell activation and maturation

Blood ◽  
2003 ◽  
Vol 102 (12) ◽  
pp. 4090-4098 ◽  
Author(s):  
Katja Brandt ◽  
Silvia Bulfone-Paus ◽  
Donald C. Foster ◽  
René Rückert
Keyword(s):  
T Cell ◽  
T Cell Activation ◽  
Cell Activation ◽  
Contact Hypersensitivity ◽  
Dendritic Cell Activation ◽  
Antigen Uptake ◽  
Interleukin 21 ◽  
Mediated Contact

Abstract Interleukin 21 (IL-21) is a newly described cytokine with homology to IL-4 and IL-15. They belong to a cytokine family that uses the common γ chain for signaling but also have their private high-affinity receptors. Since it is well known that IL-4 modulates differentiation and activation of dendritic cells (DCs), we analyzed effects of IL-21 compared with IL-15 on DC differentiation, maturation, and function. Here we show that DCs generated with granulocyte-macrophage colony-stimulating factor (GMCSF) in the presence of IL-21 (IL-21DCs) differentiated into phenotypically and functionally altered DCs characterized by reduced major histocompatibility complex class II (MHCII) expression, high antigen uptake, and low stimulatory capacity for T-cell activation in vitro. Additionally, IL-21DCs completely failed to induce antigen (Ag)-specific T-cell mediated contact hypersensitivity. Furthermore, IL-21 blocked lipopolysaccharide (LPS)-induced activation and maturation of DCs, which was not mediated by release of the anti-inflammatory cytokine IL-10. In contrast, when supplementing GMCSF with IL-15, DCs differentiated into mature antigen-presenting cells (APCs) with low antigen uptake and highly significant increased capacities to stimulate T cells in vitro and in vivo. Taken together, these results identify a dichotomous action of these structurally related cytokines on DCs, establishing IL-21 as inhibitory cytokine on DC activation and IL-15 as potent stimulator of DC function, making both cytokines interesting targets for therapeutic manipulation of DC-induced immune reactions. (Blood. 2003;102: 4090-4098)

scholarly journals Successful T cell priming in B cell-deficient mice.

1995 ◽  
Vol 182 (4) ◽  
pp. 915-922 ◽  
Author(s):  
M M Epstein ◽  
F Di Rosa ◽  
D Jankovic ◽  
A Sher ◽  
P Matzinger
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cells ◽  
B Cell ◽  
Protein Antigens ◽  
Capture Process ◽  
T Cell Priming ◽  
Deficient Mice

B cells are an abundant population of lymphocytes that can efficiently capture, process, and present antigen for recognition by activated or memory T cells. Controversial experiments and arguments exist, however, as to whether B cells are or should be involved in the priming of virgin T cells in vivo. Using B cell-deficient mice, we have studied the role of B cells as antigen-presenting cells in a wide variety of tests, including assays of T cell proliferation and cytokine production in responses to protein antigens, T cell killing to minor and major histocompatibility antigens, skin graft rejection, and the in vitro and in vivo responses to shistosome eggs. We found that B cells are not critical for either CD4 or CD8 T cell priming in any of these systems. This finding lends support to the notion that the priming of T cells is reserved for specialized cells such as dendritic cells and that antigen presentation by B cells serves distinct immunological functions.

scholarly journals The induction of cell-mediated immunity and tolerance with protein antigens coupled to syngeneic lymphoid cells.

1979 ◽  
Vol 149 (3) ◽  
pp. 758-773 ◽  
Author(s):  
S D Miller ◽  
R P Wetzig ◽  
H N Claman
Keyword(s):  
T Cells ◽  
Lymph Node ◽  
T Cell ◽  
Lymphoid Cells ◽  
Delayed Hypersensitivity ◽  
Cell Mediated Immunity ◽  
Protein Antigens ◽  
Cyt C

A mouse model of cell-mediated immunity (CMI) and tolerance to protein antigens horse gamma globulin (HoGG) and cytochrome (Cyt C) was investigated. A reliable CMI response as measured in vivo by ear swelling or by an in vitro T-cell proliferation assay could be induced by one of two methods: (a) sensitization by antigen-complete Freund's adjuvant in the base of the tail, or (b) sensitization by s.c. injection of antigen coupled to syngeneic lymphoid cells. The in vivo response exhibited characteristic CMI parameters, delayed kinetics, and transfer by viable T cells. Prior i.v. injection of HoGG-modified lymphoid cells (HoGG-LC) or Cyt C-LC before sensitization resulted in a rapidly induced, dose-dependent, antigen-specific suppression of both in vivo and in vitro manifestations of the CMI response. In addition, tolerance in this system was transferrable by an antigen-specific suppressor T cell (Ts). The Ts were found to diminish the in vivo ear swelling reaction in recipient animals, but had no effect on the in vitro T-cell proliferative response of the recipients. In contrast to the rapid development of tolerance in donor mice (phenotypic tolerance), transferrable Ts were first demonstrable 4--7 d posttolerization. This latter result indicates that at least two mechanisms of tolerance are operative in this system: the rapid induction of clone inhibition of reactive T cells and the slower induction of Ts. These results indicate again that the mode of antigen presentation is crucial in determining the immunologic outcome. In these experiments, cell-bound proteins injected subcutaneously led to delayed hypersensitivity while the same antigens injected intravenously led to tolerance. These results are considered in the light of recent experiments which show that T cells recognize antigens on cells in association with major histocompatibility complex products. We believe the following pathways are involved. In sensitization via subcutaneous injection of HoGG-LC, antigen reaches the lymph node via lymphatic pathways which lead to immunogenic macrophage-associated presentation and the activation of delayed hypersensitivity T cells (TDH). In tolerization via intravenous injection of HoGG-LC, antigen (a) reaches the lymph node via the blood, probably directly meeting the TDH, preventing its subsequent activation by immunogenic HoGG (clone inhibition) and (b) reaches the spleen, also via the blood, activating suppressor T cells.

Sign in / Sign up

Export Citation Format

Share Document