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Asian Pacific Journal of Tropical... May 2016To investigate the correlation between activation of toll-like receptors 3 (TLR3) signaling pathway and tumor-associated macrophage and its effect on the tumor growth.
OBJECTIVE
To investigate the correlation between activation of toll-like receptors 3 (TLR3) signaling pathway and tumor-associated macrophage and its effect on the tumor growth.
METHODS
The mice Lewis lung cancer cell lines 3LL and melanoma B16H10 were used to construct the subcutaneous transplantation tumor models and then they were treated with Poly-ICLC. The curative effect was observed and then the T cell and macrophage phenotypes infiltrated in local tumor were detected by flow cytometry. After the in vitro culture of mouse bone marrow-derived macrophage, the real-time PCR and western blot were applied to detect the expression of macrophage activation markers and the activation of intracellular signaling pathways.
RESULTS
The survival time of mice with brown tumor treated with Poly-ICLC significantly increased and the tumor growth was inhibited. The ratio of local tumor-infiltrated Treg decreased, while the ratio of CD8(+) T cell increased significantly. The macrophages surface CD206 expression was down-regulated while the expression of iNOS increased. The Poly-ICLC could promote the expression of M1 markers (IL-1β, TNF-α and iNOS) in bone marrow-derived macrophage and inhibited the expression of M2 molecules (Arg-1, YM-1 and CD206). The phosphorylation level of downstream p65, TBK1 and IRF3 increased significantly.
CONCLUSIONS
The Poly-ICLC can activate the TLR3 downstream signaling pathway to induce a M1 polarization of tumor associated macrophage, thereby inhibiting the tumor growth.
PubMed: 27261859
DOI: 10.1016/j.apjtm.2016.03.019 -
PloS One 2016Improved antigenicity against HIV-1 envelope (Env) protein is needed to elicit vaccine-induced protective immunity in humans. Here we describe the first tests in...
Improved antigenicity against HIV-1 envelope (Env) protein is needed to elicit vaccine-induced protective immunity in humans. Here we describe the first tests in non-human primates (NHPs) of Env gp140 protein fused to a humanized anti-LOX-1 recombinant antibody for delivering Env directly to LOX-1-bearing antigen presenting cells, especially dendritic cells (DC). LOX-1, or 1ectin-like oxidized low-density lipoprotein (LDL) receptor-1, is expressed on various antigen presenting cells and endothelial cells, and is involved in promoting humoral immune responses. The anti-LOX-1 Env gp140 fusion protein was tested for priming immune responses and boosting responses in animals primed with replication competent NYVAC-KC Env gp140 vaccinia virus. Anti-LOX-1 Env gp140 vaccination elicited robust cellular and humoral responses when used for either priming or boosting immunity. Co-administration with Poly ICLC, a TLR3 agonist, was superior to GLA, a TLR4 agonist. Both CD4+ and CD8+ Env-specific T cell responses were elicited by anti-LOX-1 Env gp140, but in particular the CD4+ T cells were multifunctional and directed to multiple epitopes. Serum IgG and IgA antibody responses induced by anti-LOX-1 Env gp140 against various gp140 domains were cross-reactive across HIV-1 clades; however, the sera neutralized only HIV-1 bearing sequences most similar to the clade C 96ZM651 Env gp140 carried by the anti-LOX-1 vehicle. These data, as well as the safety of this protein vaccine, justify further exploration of this DC-targeting vaccine approach for protective immunity against HIV-1.
Topics: AIDS Vaccines; Animals; Antibodies, Monoclonal, Humanized; Antibodies, Viral; Antibody Specificity; HIV-1; Humans; Macaca mulatta; Male; Mice; Recombinant Fusion Proteins; Scavenger Receptors, Class E; T-Lymphocytes; env Gene Products, Human Immunodeficiency Virus
PubMed: 27077384
DOI: 10.1371/journal.pone.0153484 -
Cancer Immunology, Immunotherapy : CII Feb 2017The design of efficacious and cost-effective therapeutic vaccines against cancer remains both a research priority and a challenge. For more than a decade, our laboratory... (Review)
Review
The design of efficacious and cost-effective therapeutic vaccines against cancer remains both a research priority and a challenge. For more than a decade, our laboratory has been involved in the development of synthetic peptide-based anti-cancer therapeutic vaccines. We first dedicated our efforts in the identification and validation of peptide epitopes for both CD8 and CD4 T cells from tumor-associated antigens (TAAs). Because of suboptimal immune responses and lack of therapeutic benefit of peptide vaccines containing these epitopes, we have focused our recent efforts in optimizing peptide vaccinations in mouse tumor models using numerous TAA epitopes. In this focused research review, we describe how after taking lessons from the immune system's way of dealing with acute viral infections, we have designed peptide vaccination strategies capable of generating very high numbers of therapeutically effective CD8 T cells. We also discuss some of the remaining challenges to translate these findings into the clinical setting.
Topics: Animals; Cancer Vaccines; Disease Models, Animal; Humans; Melanoma, Experimental; Vaccines, Subunit; Virus Diseases
PubMed: 27052572
DOI: 10.1007/s00262-016-1834-5 -
Neuro-oncology Aug 2016Low-grade gliomas (LGGs) are the most common brain tumors of childhood. Although surgical resection is curative for well-circumscribed superficial lesions, tumors that...
BACKGROUND
Low-grade gliomas (LGGs) are the most common brain tumors of childhood. Although surgical resection is curative for well-circumscribed superficial lesions, tumors that are infiltrative or arise from deep structures are therapeutically challenging, and new treatment approaches are needed. Having identified a panel of glioma-associated antigens (GAAs) overexpressed in these tumors, we initiated a pilot trial of vaccinations with peptides for GAA epitopes in human leukocyte antigen-A2+ children with recurrent LGG that had progressed after at least 2 prior regimens.
METHODS
Peptide epitopes for 3 GAAs (EphA2, IL-13Rα2, and survivin) were emulsified in Montanide-ISA-51 and administered subcutaneously adjacent to intramuscular injections of polyinosinic-polycytidylic acid stabilized by lysine and carboxymethylcellulose every 3 weeks for 8 courses, followed by booster vaccines every 6 weeks. Primary endpoints were safety and T-lymphocyte responses against GAA epitopes. Treatment response was evaluated clinically and by MRI.
RESULTS
Fourteen children were enrolled. Other than grade 3 urticaria in one child, no regimen-limiting toxicity was encountered. Vaccination induced immunoreactivity to at least one vaccine-targeted GAA in all 12 evaluable patients: to IL-13Rα2 in 3, EphA2 in 11, and survivin in 3. One child with a metastatic LGG had asymptomatic pseudoprogression noted 6 weeks after starting vaccination, followed by dramatic disease regression with >75% shrinkage of primary tumor and regression of metastatic disease, persisting >57 months. Three other children had sustained partial responses, lasting >10, >31, and >45 months, and one had a transient response.
CONCLUSIONS
GAA peptide vaccination in children with recurrent LGGs is generally well tolerated, with preliminary evidence of immunological and clinical activity.
Topics: Adolescent; Antigens, Neoplasm; Brain Neoplasms; Carboxymethylcellulose Sodium; Child; Child, Preschool; Disease-Free Survival; Epitopes; Female; Glioma; Humans; Infant; Inhibitor of Apoptosis Proteins; Interferon Inducers; Interleukin-13 Receptor alpha2 Subunit; Male; Neoplasm Grading; Pilot Projects; Poly I-C; Polylysine; Receptor, EphA2; Survivin; Treatment Outcome; Vaccination
PubMed: 26984745
DOI: 10.1093/neuonc/now026 -
Journal of Advanced Research Mar 2016Given the self nature of cancer, anti-tumor immune response is weak. As such, acute inflammation induced by microbial products can induce signals that result in...
Given the self nature of cancer, anti-tumor immune response is weak. As such, acute inflammation induced by microbial products can induce signals that result in initiation of an inflammatory cascade that helps activation of immune cells. We aimed to compare the nature and magnitude of acute inflammation induced by toll-like receptor ligands (TLRLs) on the tumor growth and the associated inflammatory immune responses. To induce acute inflammation in tumor-bearing host, CD1 mice were inoculated with intraperitoneal (i.p.) injection of Ehrlich ascites carcinoma (EAC) (5 × 10(5) cells/mouse), and then treated with i.p. injection on day 1, day 7 or days 1 + 7 with: (1) polyinosinic:polycytidylic (poly(I:C)) (TLR3L); (2) Poly-ICLC (clinical grade of TLR3L); (3) Bacillus Calmette Guerin (BCG) (coding for TLR9L); (4) Complete Freund's adjuvant (CFA) (coding for TLR9L); and (5) Incomplete Freund's Adjuvant (IFA). Treatment with poly(I:C), Poly-ICLC, BCG, CFA, or IFA induced anti-tumor activities as measured by 79.1%, 75.94%, 73.94%, 71.88% and 47.75% decreases, respectively in the total number of tumor cells collected 7 days after tumor challenge. Among the tested TLRLs, both poly(I:C) (TLR3L) and BCG (contain TLR9L) showed the highest anti-tumor effects as reflected by the decrease in the number of EAc cells. These effects were associated with a 2-fold increase in the numbers of inflammatory cells expressing the myeloid markers CD11b(+)Ly6G(+), CD11b(+)Ly6G(-), and CD11b(+)Ly6G(-). We concluded that Provision of the proper inflammatory signal with optimally defined magnitude and duration during tumor growth can induce inflammatory immune cells with potent anti-tumor responses without vaccination.
PubMed: 26966565
DOI: 10.1016/j.jare.2015.06.001 -
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 -
Mucosal Immunology Sep 2016Despite significant therapeutic advances for HIV-1 infected individuals, a preventative HIV-1 vaccine remains elusive. Studies focusing on early transmission events,...
Despite significant therapeutic advances for HIV-1 infected individuals, a preventative HIV-1 vaccine remains elusive. Studies focusing on early transmission events, including the observation that there is a profound loss of gastrointestinal (GI) CD4(+) T cells during acute HIV-1 infection, highlight the importance of inducing HIV-specific immunity within the gut. Here we report on the generation of cellular and humoral immune responses in the intestines by a mucosally administered, dendritic cell (DC) targeted vaccine. Our results show that nasally delivered α-CD205-p24 vaccine in combination with polyICLC, induced polyfunctional immune responses within naso-pulmonary lymphoid sites that disseminated widely to systemic and mucosal (GI tract and the vaginal epithelium) sites. Qualitatively, while α-CD205-p24 prime-boost immunization generated CD4(+) T-cell responses, heterologous prime-boost immunization with α-CD205-p24 and NYVAC gag-p24 generated high levels of HIV-specific CD4(+) and CD8(+) T cells within the GI tract. Finally, DC-targeting enhanced the amplitude and longevity of vaccine-induced immune responses in the GI tract. This is the first report of a nasally delivered, DC-targeted vaccine to generate HIV-specific immune responses in the GI tract and will potentially inform the design of preventative approaches against HIV-1 and other mucosal infections.
Topics: AIDS Vaccines; Administration, Intranasal; Animals; Antigens, CD; Antigens, Viral; CD4-Positive T-Lymphocytes; CD8-Positive T-Lymphocytes; Carboxymethylcellulose Sodium; Dendritic Cells; Female; Gastrointestinal Tract; HIV Core Protein p24; HIV Infections; HIV-1; Humans; Immunity, Cellular; Immunity, Humoral; Immunization, Secondary; Interferon Inducers; Lectins, C-Type; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Minor Histocompatibility Antigens; Poly I-C; Polylysine; Receptors, Cell Surface; Vaccination; Viral Vaccines; gag Gene Products, Human Immunodeficiency Virus
PubMed: 26732678
DOI: 10.1038/mi.2015.133 -
Journal of Neurochemistry Feb 2016Emerging experimental evidence suggests that activation of Toll-like receptor 3 (TLR3) by its agonist polyinosinic polycytidylic acid (poly-ICLC) protects neurons...
Emerging experimental evidence suggests that activation of Toll-like receptor 3 (TLR3) by its agonist polyinosinic polycytidylic acid (poly-ICLC) protects neurons against cerebral ischemia, but the underlying mechanisms remain largely unknown. In the brain, TLR3 is mostly expressed in glial cells. Therefore, we assess the hypothesis that TLR3 activation in microglia is required for neuroprotection against ischemia. After transient focal cerebral ischemia, microglia/macrophages (MMs) demonstrate a significant reduction in TLR3 and its downstream cytokine interleukin 6 (IL-6). Subsequently, activation of TLR3 by poly-ICLC restored TLR3 expression and decreased infarction. To further investigate these mechanisms, we turned to a primary cell culture system. Consistent with the in vivo findings, oxygen-glucose deprivation (OGD) significantly reduced TLR3 and IL-6 mRNA expression in microglia, but poly-ICLC significantly rescued TLR3 and IL-6 expression. Importantly, conditioned media from OGD-treated microglia increased neuronal death after OGD. In contrast, the conditioned media from microglia treated with poly-ICLC after OGD significantly protected against OGD-induced neuron death. Taken together, our findings provide proof-of-concept that activation of TLR3 in microglia may promote neuron survival after ischemia. We assessed the hypothesis that Toll-like receptor 3 (TLR3) activation in microglia is required for neuroprotection against ischemia. After transient focal cerebral ischemia, microglia/macrophage demonstrates a reduction in TLR3 and Interleukin 6 (IL-6). Also, oxygen-glucose deprivation (OGD) reduces TLR3 and IL-6 expression in microglia, but polyinosinic polycytidylic acid (poly-ICLC) rescues TLR3 and IL-6. Importantly, conditioned media from microglia treated with poly-ICLC protects against OGD-induced neuron death. We propose that activation of TLR3 in microglia may promote neuron survival after ischemia.
PubMed: 26603372
DOI: 10.1111/jnc.13441 -
Stroke Jan 2016Preconditioning with poly-l-lysine and carboxymethylcellulose (ICLC) provides robust neuroprotection from cerebral ischemia in a mouse stroke model. However, the...
BACKGROUND AND PURPOSE
Preconditioning with poly-l-lysine and carboxymethylcellulose (ICLC) provides robust neuroprotection from cerebral ischemia in a mouse stroke model. However, the receptor that mediates neuroprotection is unknown. As a synthetic double-stranded RNA, poly-ICLC may bind endosomal Toll-like receptor 3 or one of the cytosolic retinoic acid-inducible gene-I-like receptor family members, retinoic acid-inducible gene-I, or melanoma differentiation-associated protein 5. Activation of these receptors culminates in type I interferons (IFN-α/β) induction-a response required for poly-ICLC-induced neuroprotection. In this study, we investigate the receptor required for poly-ICLC-induced neuroprotection.
METHODS
Toll-like receptor 3, melanoma differentiation-associated protein 5-, and IFN-promoter stimulator 1-deficient mice were treated with poly-ICLC 24 hours before middle cerebral artery occlusion. Infarct volume was measured 24 hours after stroke to identify the receptor signaling pathways involved in protection. IFN-α/β induction was measured in plasma samples collected 6 hours after poly-ICLC treatment. IFN-β-deficient mice were used to test the requirement of IFN-β for poly-ICLC-induced neuroprotection. Mice were treated with recombinant IFN-α-A to test the role of IFN-α as a potential mediator of neuroprotection.
RESULTS
Poly-ICLC induction of both neuroprotection and systemic IFN-α/β requires the cytosolic receptor melanoma differentiation-associated protein 5 and the adapter molecule IFN-promoter stimulator 1, whereas it is independent of Toll-like receptor 3. IFN-β is not required for poly-ICLC-induced neuroprotection. IFN-α treatment protects against stroke.
CONCLUSIONS
Poly-ICLC preconditioning is mediated by melanoma differentiation-associated protein 5 and its adaptor molecule IFN-promoter stimulator 1. This is the first evidence that a cytosolic receptor can mediate neuroprotection, providing a new target for the development of therapeutic agents to protect the brain from ischemic injury.
Topics: Animals; Brain Ischemia; Carboxymethylcellulose Sodium; DEAD-box RNA Helicases; Interferon-Induced Helicase, IFIH1; Ischemic Preconditioning; Male; Mice; Mice, Inbred C57BL; Mice, Transgenic; Neuroprotective Agents; Poly I-C; Polylysine; Stroke
PubMed: 26564103
DOI: 10.1161/STROKEAHA.115.010329 -
Cancer Discovery Jan 2016Weak and ineffective antitumor cytotoxic T lymphocyte (CTL) responses can be rescued by immunomodulatory mAbs targeting PD-1 or CD137. Using Batf3(-/-) mice, which are...
UNLABELLED
Weak and ineffective antitumor cytotoxic T lymphocyte (CTL) responses can be rescued by immunomodulatory mAbs targeting PD-1 or CD137. Using Batf3(-/-) mice, which are defective for cross-presentation of cell-associated antigens, we show that BATF3-dependent dendritic cells (DC) are essential for the response to therapy with anti-CD137 or anti-PD-1 mAbs. Batf3(-/-) mice failed to prime an endogenous CTL-mediated immune response toward tumor-associated antigens, including neoantigens. As a result, the immunomodulatory mAbs could not amplify any therapeutically functional immune response in these mice. Moreover, administration of systemic sFLT3L and local poly-ICLC enhanced DC-mediated cross-priming and synergized with anti-CD137- and anti-PD-1-mediated immunostimulation in tumor therapy against B16-ovalbumin-derived melanomas, whereas this function was lost in Batf3(-/-) mice. These experiments show that cross-priming of tumor antigens by FLT3L- and BATF3-dependent DCs is crucial to the efficacy of immunostimulatory mAbs and represents a very attractive point of intervention to enhance their clinical antitumor effects.
SIGNIFICANCE
Immunotherapy with immunostimulatory mAbs is currently achieving durable clinical responses in different types of cancer. We show that cross-priming of tumor antigens by BATF3-dependent DCs is a key limiting factor that can be exploited to enhance the antitumor efficacy of anti-PD-1 and anti-CD137 immunostimulatory mAbs.
Topics: Animals; Antibodies, Monoclonal; Basic-Leucine Zipper Transcription Factors; Cell Line, Tumor; Dendritic Cells; Humans; Immunotherapy; Lymphocyte Activation; Melanoma, Experimental; Mice; Mice, Transgenic; Programmed Cell Death 1 Receptor; Repressor Proteins; Tumor Necrosis Factor Receptor Superfamily, Member 9
PubMed: 26493961
DOI: 10.1158/2159-8290.CD-15-0510