An IL-17 peptide-based and virus-like particle vaccine enhances the bioactivity of IL-17 in vitro and in vivo

Peptide-based vaccine targeting IL17A attenuates experimental spondyloarthritis in HLA-B27 transgenic rats

OBJECTIVES

Spondyloarthritis (SpA) is known as series of immune-mediated inflammatory disease of the axial and peripheral joints. Human leucocyte antigen (HLA)-B27 is a genetic risk factor for SpA. Recent evidence suggests that the interleukin -17 (IL17) axis strongly contributes to SpA. This study aimed to assess the efficacy of an IL17A peptide-based vaccine on SpA manifestations in model rats.

METHODS

HLA-B27/human β₂-microglobulin (hβ₂M) transgenic rats were immunised with heat-inactivated Mycobacterium tuberculosis (MT) to develop spondylitis and arthritis as an experimental SpA model after immunisation with a keyhole limpet hemocyanin-conjugated IL17A peptide-based vaccine with an alum adjuvant three times. The IL17A antibody titre was assessed using ELISA, and arthritis score and joint thickness were monitored two times a week. Enzyme-linked immunospot (ELISpot) assays for IL4- and interferon-γ-secreting splenocytes were conducted to evaluate IL17A-specific T cell activation. We also evaluated the effect of IL17A vaccine in SpA therapeutic model.

RESULTS

The IL17A peptide-based vaccine with alum adjuvant successfully induced antibody production and suppressed the arthritis score and joint thickness. X-ray and histological analyses showed that enthesitis, bone destruction and new bone formation were inhibited by the IL17A vaccine. The ELISpot assay showed that the IL17A peptide-based vaccine did not elicit any IL17A-reactive T cell responses. IL17A vaccine tends to mitigate, but not significant, in SpA treatment model. These data showed that the peptide-based vaccine targeting IL17A alleviated the SpA phenotype in a heat-inactivated MT-induced SpA model in HLA-B27/hβ₂M transgenic rats.

CONCLUSIONS

IL17A peptide-based vaccine may be a therapeutic option for SpA treatment.

Multifactorial Design of a Supramolecular Peptide Anti-IL-17 Vaccine Toward the Treatment of Psoriasis

Current treatments for chronic immune-mediated diseases such as psoriasis, rheumatoid arthritis, or Crohn's disease commonly rely on cytokine neutralization using monoclonal antibodies; however, such approaches have drawbacks. Frequent repeated dosing can lead to the formation of anti-drug antibodies and patient compliance issues, and it is difficult to identify a single antibody that is broadly efficacious across diverse patient populations. As an alternative to monoclonal antibody therapy, anti-cytokine immunization is a potential means for long-term therapeutic control of chronic inflammatory diseases. Here we report a supramolecular peptide-based approach for raising antibodies against IL-17 and demonstrate its efficacy in a murine model of psoriasis. B-cell epitopes from IL-17 were co-assembled with the universal T-cell epitope PADRE using the Q11 self-assembling peptide nanofiber system. These materials, with or without adjuvants, raised antibody responses against IL-17. Exploiting the modularity of the system, multifactorial experimental designs were used to select formulations maximizing titer and avidity. In a mouse model of psoriasis induced by imiquimod, unadjuvanted nanofibers had therapeutic efficacy, which could be enhanced with alum adjuvant but reversed with CpG adjuvant. Measurements of antibody subclass induced by adjuvanted and unadjuvanted formulations revealed strong correlations between therapeutic efficacy and titers of IgG1 (improved efficacy) or IgG2b (worsened efficacy). These findings have important implications for the development of anti-cytokine active immunotherapies and suggest that immune phenotype is an important metric for eliciting therapeutic anti-cytokine antibody responses.

Development of an IL-17A DNA Vaccine to Treat Systemic Lupus Erythematosus in Mice

The interleukin-17 (IL-17) family, especially IL-17A, plays an important role in the pathogenesis of systemic lupus erythematosus (SLE). This study developed an IL-17A epitope vaccine to treat SLE in NZBWF1 and MRL/lpr mouse models. A plasmid vector encoding a hepatitis B core (HBc)-IL-17A epitope fusion protein was injected using electroporation into the skeletal muscle of NZBWF1(New Zealand Black mice x New Zealand White mice F1 hybrid strain) or MRL/lpr mice three times at 2-week intervals. As a result, anti-IL-17A antibodies were successfully produced in the HBc-IL-17A group. Accordingly, serum tumor necrosis factor alpha (TNF-α) concentrations were significantly reduced in the HBc-IL-17A group. According to pathological analysis, the IL-17A DNA vaccine significantly suppressed renal tissue damage and macrophage infiltration. Consequently, the survival rate was significantly improved in the HBc-IL-17A group. In addition, we evaluated the antigen reactivity of splenocytes from IL-17A-immunized mice using an enzyme-linked immune absorbent spot (ELISPot) assay for safety evaluation. Splenocytes from IL-17A-immunized mice were significantly stimulated by the HBc epitope peptide, but not by the IL-17A epitope or recombinant IL-17A. These results indicate that the IL-17A vaccine did not induce autoreactive T cells against endogenous IL-17A. This study demonstrates for the first time that an IL-17A DNA vaccine significantly reduced organ damage and extended survival time in lupus-prone mice.

A Comprehensive Review and Update on the Pathogenesis of Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a chronic and life-threating inflammatory disease of gastroenteric tissue characterized by episodes of intestinal inflammation. The pathogenesis of IBD is complex. Recent studies have greatly improved our knowledge of the pathophysiology of IBD, leading to great advances in the treatment as well as diagnosis of IBD. In this review, we have systemically reviewed the pathogenesis of IBD and highlighted recent advances in host genetic factors, gut microbiota, and environmental factors and, especially, in abnormal innate and adaptive immune responses and their interactions, which may hold the keys to identify novel predictive or prognostic biomarkers and develop new therapies.

Sustained suppression of IL-18 by employing a vaccine ameliorates intestinal inflammation in TNBS-induced murine colitis

Aim

To develop IL-18 peptide-based virus-like particle vaccines that elicit autoantibodies against IL-18 and to evaluate the in vivo effects of the vaccines in murine colitis.

Methods

Recombinant IL-18 vaccines were constructed, and the effects of the vaccines were evaluated in trinitrobenzene sulfonic acid-induced acute and chronic colitis in mice.

Results

Two murine IL-18 peptide-based vaccines (A and D) were developed, which induced relative long-lasting specific antibodies against IL-18. Vaccine-immunized mouse antisera could partially block IL-18-induced IFN-γ production in vitro. Mice receiving vaccine D, not vaccine A, had a significant decrease in intestinal inflammation, collagen deposition and pro-inflammatory cytokine levels in colon tissue.

Conclusion

IL-18 vaccine may provide a potential therapeutic approach in the treatment of Crohn's disease.

A virus-like particle-based connective tissue growth factor vaccine suppresses carbon tetrachloride-induced hepatic fibrosis in mice

Connective tissue growth factor (CTGF) has been recognized as a central mediator and promising therapeutic target in hepatic fibrosis. In this study, we generated a novel virus-like particle (VLP) CTGF vaccine by inserting the 138–159 amino acid (aa) fragment of CTGF into the central c/e1 epitope of C-terminus truncated hepatitis B virus core antigen (HBc, aa 1–149) using a prokaryotic expression system. Immunization of BALB/c mice with the VLP vaccine efficiently elicited the production of anti-CTGF neutralizing antibodies. Vaccination with this CTGF vaccine significantly protected BALB/c mice from carbon tetrachloride (CCl₄)-induced hepatic fibrosis, as indicated by decreased hepatic hydroxyproline content and lower fibrotic score. CCl₄ intoxication-induced hepatic stellate cell activation was inhibited by the vaccination, as indicated by decreased α-smooth muscle actin expression and Smad2 phosphorylation. Vaccination against CTGF also attenuated the over-expression of some profibrogenic factors, such as CTGF, transforming growth factor-β1, platelet-derived growth factor-B and tissue inhibitor of metalloproteinase-1 in the fibrotic mouse livers, decreased hepatocyte apoptosis and accelerated hepatocyte proliferation in the fibrotic mouse livers. Our results clearly indicate that vaccination against CTGF inhibits fibrogenesis, alleviates hepatocyte apoptosis and facilitate hepatic regeneration. We suggest that the vaccine should be developed into an effective therapeutic measure for hepatic fibrosis.

Beyond passive immunization: toward a nanoparticle-based IL-17 vaccine as first in class of future immune treatments

Nanoparticles occur naturally as part of repetitive molecular structures forming virus-like particles (VLPs). VLPs are powerful immune activators. Specifically, VLP can elicit a direct activation of B lymphocytes to trigger production of antibodies targeted at molecules chemically linked to the VLP. We here review recent data from genetics research, large-scale genomic sequencing, as well as clinical trials which suggest that a VLP-based vaccine against the signaling molecule IL-17 will be safe and effective in the common skin disease psoriasis, as well as other conditions. Active vaccination against IL-17 is capable of replacing the costly manufacture of antibodies currently in clinical use with huge implications for treatment availability and health economics.

Virus-like particles presenting interleukin-33 molecules: immunization characteristics and potentials of blockingIL-33/ST2 pathway in allergic airway inflammation

We sought to develop an IL-33 vaccine and evaluate its efficacy in a mouse model of asthma. The full-length molecules of putative mature IL-33 were inserted into the immunodominant epitope region of hepatitis B core antigen using gene recombination techniques. The expressed chimeric protein presented as virus-like particles (VLPs) under observation using an electron microscopy. To investigate immunization characteristics of the VLPs, mice were immunized by using different doses, adjuvants, and routes. The VLPs induced sustained and high titers of IL-33-specific IgG and IgA even without the use of a conventional adjuvant, and the lowered ratio of IgG1/IgG2a in vaccinated mice indicated a shift from Th2 to Th1-like responses. To assess the vaccine effects on blocking the signaling of IL-33/ST2 pathway, mice receiving 3 vaccinations subjected to intraperitoneal sensitization and intranasal challenge with ovalbumin (OVA). Control animals received carrier or PBS in place of the vaccine. Immunization with the VLPs significantly suppressed inflammatory cell number and IL-33 level in BALF. OVA -induced goblet cell hyperplasia and lung tissue inflammatory cell infiltration were significantly suppressed in vaccinated mice. Our data indicate that IL-33 molecule-based vaccine, which may block IL-33/ST2 signaling pathway on a persistent basis, holds potential for treatment of asthma and, by extension, other diseases where overexpressed IL-33 plays a pivotal role in pathogenesis.

IL-17RA in intestinal inflammation: structure, signaling, function, and clinical application

: Interleukin-17 receptor A (IL-17RA) is responsible for both IL-17A and IL-25 (IL-17E) signaling pathways. Current evidences suggest distinct but interactive responses between IL-17A and IL-25 signaling, both of which are critical for intestinal immune homeostasis. IL-17RA is assumed to regulate this counterbalance and therefore becomes a crucial molecule in mucosal immunology. In this review, we will describe the structure of IL-17RA, compare IL-17A and IL-25 signaling pathways, and emphasize on the function of IL-17RA in intestinal inflammation and discuss current evidences of accomplished and ongoing clinical trials with monoclonal antibodies targeting Th17 pathway, especially IL-17RA.

The role and potential therapeutic application of myeloid-derived suppressor cells in TNBS-induced colitis

MDSCs, a heterogeneous population of cells that expand during many pathogenic conditions, have remarkable abilities to suppress T cell responses. Their role in murine colitis, induced by TNBS and therapeutic application, remains unclear. Murine colitis was induced through intrarectally administrating TNBS, twice. MDSCs in spleen and colonic LPMCs were identified using flow cytometric analysis. In adoptive transfer, MDSCs were isolated from spleen after TNBS challenges by using microbeads or generated in vitro by coculturing bone marrow cells with HSCs and then transferred into naïve mice. Two hours later, mice were then challenged with TNBS, once/week for 2 weeks. The mice were killed four days after the second TNBS delivery, and intestinal inflammation and cytokine levels and MDSC percentages were evaluated. The percentages of CD11b+Gr-1+MDSCs and subsets (CD11b+Ly6C+ and CD11b+Ly6G+MDSCs) were increased in spleen and/or colonic LPMCs in colitis mice and also correlated with the severity of intestinal inflammation. MDSCs isolated from colitis mice suppressed the proliferation of splenocytes in vitro. Adoptive transfer of MDSCs, isolated from colitis mice or generated in vitro, decreased intestinal inflammation, levels of IFN-γ, IL-17, and TNF, and percentages of spleen MDSCs when compared with controls. MDSCs that have inhibitory function in vitro and in vivo are increased and correlated with intestinal inflammation, suggesting that they may be used as a biomarker of disease activity and a cell-based biotherapy in IBD.

Inhibition of IL-17 as a pharmacological approach for IBD

Several experimental approaches have been utilized, in order to critically examine the roles of IL-17 family members in intestinal inflammation. These approaches have included: (1) the use of IL-17A and IL-17F-deficient mice, (2) specific antibodies directed against IL-17, (3) an IL-17 vaccine, (4) methods to block the IL-17 receptor and (5) small-molecule inhibitors of IL-17. Previous studies found somewhat conflicting results in preclinical models of Inflammatory Bowel Disease (IBD), using specific strains of IL-17-deficient mice. This paper will review the preclinical results using various pharmacological approaches [specific IL-17 antibodies, an IL-17 receptor fusion protein, IL-12/IL-23 p40 subunit and IL-17 vaccine approaches, as well as a small molecule inhibitor (Vidofludimus)] to inhibit IL-17 in animal models of IBD. Recent clinical results in patients with IBD will also be discussed for Secukinumab (an IL-17A antibody), Brodalumab (an IL-17 receptor antibody) and two small-molecule drugs (Vidofludimus and Tofacitinib), which inhibit IL-17 as part of their overall pharmacological profiles. This review paper will also discuss some pharmacological lessons learned from the preclinical and clinical studies with anti-IL-17 drugs, as related to drug pharmacodynamics, IL-17 receptor subtypes and other pertinent factors. Finally, future pharmacological approaches of interest will be discussed, such as: (1) Retinoic acid receptor-related orphan nuclear receptor gamma t (Rorγt) antagonists, (2) Retinoic acid receptor alpha (RARα) antagonists, (3) Pim-1 kinase inhibitors and (4) Dual small-molecule inhibitors of NF-κB and STAT3, like synthetic triterpenoids.