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1.
Entamoeba histolytica Trophozoites and Lipopeptidophosphoglycan Trigger Human Neutrophil Extracellular Traps.
Ávila, EE, Salaiza, N, Pulido, J, Rodríguez, MC, Díaz-Godínez, C, Laclette, JP, Becker, I, Carrero, JC
PloS one. 2016;(7):e0158979
Abstract
Neutrophil defense mechanisms include phagocytosis, degranulation and the formation of extracellular traps (NET). These networks of DNA are triggered by several immune and microbial factors, representing a defense strategy to prevent microbial spread by trapping/killing pathogens. This may be important against Entamoeba histolytica, since its large size hinders its phagocytosis. The aim of this study was to determine whether E. histolytica and their lipopeptidophosphoglycan (EhLPPG) induce the formation of NETs and the outcome of their interaction with the parasite. Our data show that live amoebae and EhLPPG, but not fixed trophozoites, induced NET formation in a time and dose dependent manner, starting at 5 min of co-incubation. Although immunofluorescence studies showed that the NETs contain cathelicidin LL-37 in close proximity to amoebae, the trophozoite growth was only affected when ethylene glycol tetra-acetic acid (EGTA) was present during contact with NETs, suggesting that the activity of enzymes requiring calcium, such as DNases, may be important for amoeba survival. In conclusion, E. histolytica trophozoites and EhLPPG induce in vitro formation of human NETs, which did not affect the parasite growth unless a chelating agent was present. These results suggest that NETs may be an important factor of the innate immune response during infection with E. histolytica.
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2.
Balancing the effect of corona on therapeutic efficacy and macrophage uptake of lipid nanocapsules.
Sánchez-Moreno, P, Buzón, P, Boulaiz, H, Peula-García, JM, Ortega-Vinuesa, JL, Luque, I, Salvati, A, Marchal, JA
Biomaterials. 2015;:266-78
Abstract
Several studies have shown the potential of biocompatible lipid nanocapsules as hydrophobic drug delivery systems. Understanding the factors that determine the interactions of these oil-in-water nanoemulsions with cells is a necessary step to guide the design of the most effective formulations. The aim of this study was to probe the ability of two surfactants with a markedly different nature, a non-ionic poloxamer, and a charged phospholipid, to prepare formulations with shells of different composition and different surface properties. Thus we determined their effects on the interaction with biological environments. In particular, we investigated how the shell formulation affected the adsorption of biomolecules from the surrounding biological fluids on the nanocapsule surface (corona formation). A complete physicochemical characterization including an isothermal titration calorimetry (ITC) study revealed that the use of poloxamer led to nanocapsules with a marked reduction in the number of protein-binding sites. Surface hydrophilicity and changes in corona formation strongly correlated to changes in uptake by cancer cells and by macrophages. Our results indicate that the nature and concentration of surfactants in the nanocapsules can be easily manipulated to effectively modulate their surface architecture with the aim of controlling the environmental interactions, thus optimizing functionality for in vivo applications. In particular, addition of surfactants that reduce protein binding can modulate nanoparticle clearance by the immune system, but also screens the desired interactions with cells, leading to lower uptake, thus lower therapeutic efficacy. The two effects need to be balanced in order to obtain successful formulations.
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3.
Low-dose cyclophosphamide enhances antigen-specific CD4(+) T cell responses to NY-ESO-1/ISCOMATRIX™ vaccine in patients with advanced melanoma.
Klein, O, Davis, ID, McArthur, GA, Chen, L, Haydon, A, Parente, P, Dimopoulos, N, Jackson, H, Xiao, K, Maraskovsky, E, et al
Cancer immunology, immunotherapy : CII. 2015;(4):507-18
Abstract
Clinical outcomes from cancer vaccine trials in patients with advanced melanoma have so far been disappointing. This appears at least partially due to a state of immunosuppression in these patients induced by an expansion of regulatory cell populations including regulatory T cells (Tregs). We have previously demonstrated potent immunogenicity of the NY-ESO-1/ISCOMATRIX™ vaccine in patients with resected melanoma (study LUD99-08); however, the same vaccine induced only a few vaccine antigen-specific immune responses in patients with advanced disease (study LUD2002-013). Pre-clinical models suggest that the alkylating agent cyclophosphamide can enhance immune responses by depleting Tregs. Therefore, we have enrolled a second cohort of patients with advanced melanoma in the clinical trial LUD2002-013 to investigate whether pre-treatment with cyclophosphamide could improve the immunogenicity of the NY-ESO-1/ISCOMATRIX™ vaccine. The combination treatment led to a significant increase in vaccine-induced NY-ESO-1-specific CD4(+) T cell responses compared with the first trial cohort treated with vaccine alone. We could not detect a significant decline in regulatory T cells in peripheral blood of patients 14 days after cyclophosphamide administration, although a decline at an earlier time point cannot be excluded. Our observations support the inclusion of cyclophosphamide in combination trials with vaccines and other immune-modulatory agents.
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4.
ISCOMATRIX™ adjuvant promotes epitope spreading and antibody affinity maturation of influenza A H7N9 virus like particle vaccine that correlate with virus neutralization in humans.
Chung, KY, Coyle, EM, Jani, D, King, LR, Bhardwaj, R, Fries, L, Smith, G, Glenn, G, Golding, H, Khurana, S
Vaccine. 2015;(32):3953-62
Abstract
In a previously reported phase I clinical trial, subjects vaccinated with two doses of an unadjuvanted H7N9 virus like particle (VLP) vaccine responded poorly (15.6% seroconversion rates with 45μg hemagglutinin (HA) dose). In contrast, 80.6% of subjects receiving H7N9 VLP vaccine (5μg HA) with ISCOMATRIX™ adjuvant developed hemagglutination-inhibition (HI) responses. To better understand the role of adjuvant, complete antibody epitope repertoires of post-vaccination sera were investigated using Whole Genome Fragment Phage Display Library (GFPDL). In addition, antibody affinity maturation following vaccination was measured against HA1 and HA2 antigenic domains using real time Surface Plasmon Resonance (SPR) based kinetic assays. Unadjuvanted H7N9-VLP vaccine generated primarily antibodies targeting the C-terminus of the HA1 domain, predicted to be mostly buried on the native HA spikes, while adjuvanted VLP vaccine generated antibodies against large epitopes in the HA1 spanning the receptor binding domain (RBD). SPR analysis using a functional H7-HA1 domain demonstrated that sera from adjuvanted H7N9-VLP vaccine induced higher total binding antibodies and significantly higher antibody affinity maturation to HA1 compared to sera from unadjuvanted vaccine. Total antibody binding and affinity to the HA1 (but not HA2) domain correlated with HI and neutralization titers. This study demonstrates that ISCOMATRIX™ adjuvanted vaccine promotes higher quality antibody immune response against avian influenza in naïve humans.
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5.
Supplementation of a dairy drink enriched with milk phospholipids in patients with atopic dermatitis - a double-blind, placebo-controlled, randomized, cross-over study.
Keller, S, Le, HY, Rödiger, C, Hipler, UC, Kertscher, R, Malarski, A, Hunstock, LM, Kiehntopf, M, Kaatz, M, Norgauer, J, et al
Clinical nutrition (Edinburgh, Scotland). 2014;(6):1010-6
Abstract
BACKGROUND & AIMS Reduced epidermal ceramide content may lead to an impaired skin barrier in atopic dermatitis. Plasma concentration of the ceramide precursor sphingomyelin increases after milk-fat consumption due to affected lipoprotein metabolism, although sphingomyelin, a main component of milk phospholipids, might also directly influence plasma sphingomyelin levels. The aim was to determine whether supplementation of a dairy drink with milk phospholipids improves skin parameters and influences plasma lipid profile. METHODS In a double-blind cross-over study, 39 patients were randomized into 2 groups and daily received phospholipid milk (3 g phospholipids ≙ 0.75 g sphingomyelin) or normal whole milk as placebo control for 6 weeks. SCORAD indices, serum immune and plasma lipid parameters were determined. RESULTS SCORAD indices did not differ between groups following control and phospholipid milk supplementation (control milk: 10.9 ± 5.9 vs. phospholipid milk: 11.7 ± 6.9, P = 0.416), but were significantly decreased compared to baseline (baseline: 15.6 ± 8.8, P < 0.05). Plasma sphingomyelin proportions were also similar after the treatments (control milk: 27.5 ± 2.3 vs. phospholipid milk: 27.4 ± 2.6% of total phospholipids, P = 0.894), but were significantly increased compared to baseline (20.7 ± 2.4% of total phospholipids, P < 0.05). CONCLUSIONS Supplementation of a dairy drink with milk phospholipids has no beneficial effect on skin parameters compared to consumption of whole milk in patients with atopic dermatitis. To elucidate an impact of the plasma sphingomyelin proportion on skin conditions, further studies are necessary. Clinical trial ID: Registered under ClinicalTrials.gov. Identifier no. NCT01326520.
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6.
ISCOMATRIX: a novel adjuvant for use in prophylactic and therapeutic vaccines against infectious diseases.
Baz Morelli, A, Becher, D, Koernig, S, Silva, A, Drane, D, Maraskovsky, E
Journal of medical microbiology. 2012;(Pt 7):935-943
Abstract
The ISCOMATRIX adjuvant has antigen delivery and presentation properties as well as immunomodulatory capabilities, which combine to provide enhanced and accelerated immune responses. The responses are broad, including a range of subclasses of antibodies as well as CD4(+) and CD8(+) T-cells. A range of ISCOMATRIX vaccines (ISCOMATRIX adjuvant combined with antigen) have now been tested in clinical trials and have been shown to be generally safe and well tolerated as well as immunogenic, generating both antibody (Ab) and T-cell responses. The mechanisms by which ISCOMATRIX adjuvant facilitates its immune effects are the scope of significant study and indicate that ISCOMATRIX adjuvant (i) rapidly traffics antigen into the cytosol of multiple dendritic cell subsets, (ii) induces the induction of an array of cytokines and chemokines and (iii) links the innate and adaptive immune responses in vivo in a Toll-like-receptor-independent but MyD88-dependent manner. These data highlight the clinical utility of ISCOMATRIX adjuvant in the development of prophylactic and therapeutic vaccines for infectious disease.
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7.
Regulatory T-cell-mediated attenuation of T-cell responses to the NY-ESO-1 ISCOMATRIX vaccine in patients with advanced malignant melanoma.
Nicholaou, T, Ebert, LM, Davis, ID, McArthur, GA, Jackson, H, Dimopoulos, N, Tan, B, Maraskovsky, E, Miloradovic, L, Hopkins, W, et al
Clinical cancer research : an official journal of the American Association for Cancer Research. 2009;(6):2166-73
Abstract
PURPOSE NY-ESO-1 is a highly immunogenic antigen expressed in a variety of malignancies, making it an excellent target for cancer vaccination. We recently developed a vaccine consisting of full-length recombinant NY-ESO-1 protein formulated with ISCOMATRIX adjuvant, which generated strong humoral and T-cell-mediated immune responses and seemed to reduce the risk of disease relapse in patients with fully resected melanoma. This study examines the clinical and immunologic efficacy of the same vaccine in patients with advanced metastatic melanoma. EXPERIMENTAL DESIGN Delayed-type hypersensitivity responses, circulating NY-ESO-1-specific CD4(+) and CD8(+) T cells, and proportions of regulatory T cells (Treg) were assessed in patients. RESULTS In contrast to patients with minimal residual disease, advanced melanoma patients showed no clinical responses to vaccination. Although strong antibody responses were mounted, the generation of delayed-type hypersensitivity responses was significantly impaired. The proportion of patients with circulating NY-ESO-1-specific CD4(+) T cells was also reduced, and although many patients had CD8(+) T cells specific to a broad range of NY-ESO-1 epitopes, the majority of these responses were preexisting. Tregs were enumerated in the blood by flow cytometric detection of cells with a CD4(+)CD25(+)FoxP3(+) and CD4(+)CD25(+)CD127(-) phenotype. Patients with advanced melanoma had a significantly higher proportion of circulating Treg compared with those with minimal residual disease. CONCLUSIONS Our results point to a tumor-induced systemic immune suppression, showing a clear association between the stage of melanoma progression, the number of Treg in the blood, and the clinical and immunologic efficacy of the NY-ESO-1 ISCOMATRIX cancer vaccine.
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8.
Phospholipid membrane abnormalities and reduced niacin skin flush response in schizophrenia.
Buretić-Tomljanović, A, Giacometti, J, Nadalin, S, Rubesa, G, Vulin, M, Tomljanović, D
Psychiatria Danubina. 2008;(3):372-83
Abstract
OBJECTIVES Reduced n-3 and n-6 polyunsaturated fatty acids (PUFAs) content in red blood cell (RBC) membranes and abnormal membrane phospholipid metabolism were repeatedly implicated in the etiology of schizophrenia. FINDINGS Prenatal and perinatal depletion of PUFAs interferes with normal brain development and function. The lack of docosahexaenoic acid - DHA in the brain is reflected in lower membrane DHA/AA (AA - arachidonic acid) ratio, increased activity of AA-metabolizing enzymes, and disturbance of downstream metabolic pathways involved in signaling, growth modulation, brain glucose uptake, immune functions, neurotransmission, synaptogenesis and neurogenesis. Preliminary high-throughput metabolomic studies revealed abnormal biochemical profile in patients with schizophrenia or brief psychotic disorder when compared to healthy controls. The results of both metabolomic and proteomic studies pointed to energy metabolism and lipid biosynthesis being impaired in schizophrenia. The usefulness of antipsychotic medication and supplementation with PUFAs in reverting to the normal metabolic state has been suggested in early treatment of the first psychotic episode. Abnormalities of phospholipid metabolism can be also detected as attenuated niacin skin flush response in the variety of neuropsychiatric disorders. CONCLUSIONS Disturbances of lipid homeostasis could represent biochemical markers in the preclinical phase of neuropsychiatric illnesses and could serve as triggers in genetically vulnerable individuals. The assessment of patients' lipid status may also help in monitoring the course of the disease and treatment response. In this regard, simple, cheap and fast niacin skin flush test might be valuable. It might help in diagnosis of adolescents and young adults with psychotic behaviour, or in defining the necessity for long-term antipsychotic therapy. Along with antipsychotic medication schizophrenic patients need specific medical nutrition therapies.
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9.
Phase 1 study of HPV16-specific immunotherapy with E6E7 fusion protein and ISCOMATRIX adjuvant in women with cervical intraepithelial neoplasia.
Frazer, IH, Quinn, M, Nicklin, JL, Tan, J, Perrin, LC, Ng, P, O'Connor, VM, White, O, Wendt, N, Martin, J, et al
Vaccine. 2004;(2):172-81
Abstract
PURPOSE Persistent infection of cervical epithelium with "high risk" human papillomavirus (HPV) results in cervical intraepithelial neoplasia (CIN) from which squamous cancer of the cervix can arise. A study was undertaken to evaluate the safety and immunogenicity of an HPV16 immunotherapeutic consisting of a mixture of HPV16 E6E7 fusion protein and ISCOMATRIX adjuvant (HPV16 Immunotherapeutic) for patients with CIN. EXPERIMENTAL DESIGN Patients with CIN (n = 31) were recruited to a randomised blinded placebo controlled dose ranging study of immunotherapy. RESULTS Immunotherapy was well tolerated. Immunised subjects developed HPV16 E6E7 specific immunity. Antibody, delayed type hypersensitivity, in vitro cytokine release, and CD8 T cell responses to E6 and E7 proteins were each significantly greater in the immunised subjects than in placebo recipients. Loss of HPV16 DNA from the cervix was observed in some vaccine and placebo recipients. CONCLUSIONS The HPV16 Immunotherapeutic comprising HPV16E6E7 fusion protein and ISCOMATRIX adjuvant is safe and induces vaccine antigen specific cell mediated immunity.