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1.
Immunogenetics ; 70(6): 363-372, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29196796

RESUMO

Around 30% of individuals will develop herpes zoster (HZ), caused by the varicella zoster virus (VZV), during their life. While several risk factors for HZ, such as immunosuppressive therapy, are well known, the genetic and molecular components that determine the risk of otherwise healthy individuals to develop HZ are still poorly understood. We created a computational model for the Human Leukocyte Antigen (HLA-A, -B, and -C) presentation capacity of peptides derived from the VZV Immediate Early 62 (IE62) protein. This model could then be applied to a HZ cohort with known HLA molecules. We found that HLA-A molecules with poor VZV IE62 presentation capabilities were more common in a cohort of 50 individuals with a history of HZ compared to a nationwide control group, which equated to a HZ risk increase of 60%. This tendency was most pronounced for cases of HZ at a young age, where other risk factors are less prevalent. These findings provide new molecular insights into the development of HZ and reveal a genetic predisposition in those individuals most at risk to develop HZ.


Assuntos
Antígenos HLA-A/imunologia , Herpes Zoster/imunologia , Herpesvirus Humano 3/imunologia , Proteínas Imediatamente Precoces/imunologia , Transativadores/imunologia , Proteínas do Envelope Viral/imunologia , Adulto , Idoso , Bélgica/epidemiologia , Varicela/imunologia , Varicela/virologia , Feminino , Predisposição Genética para Doença , Herpes Zoster/epidemiologia , Herpes Zoster/genética , Humanos , Proteínas Imediatamente Precoces/genética , Masculino , Pessoa de Meia-Idade , Modelos Imunológicos , Fatores de Risco , Transativadores/genética , Proteínas do Envelope Viral/genética
2.
Acta Neuropathol ; 136(6): 939-953, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30284034

RESUMO

Motor neurons containing aggregates of superoxide dismutase 1 (SOD1) are hallmarks of amyotrophic lateral sclerosis (ALS) caused by mutations in the gene encoding SOD1. We have previously reported that two strains of mutant human (h) SOD1 aggregates (denoted A and B) can arise in hSOD1-transgenic models for ALS and that inoculation of such aggregates into the lumbar spinal cord of mice results in rostrally spreading, templated hSOD1 aggregation and premature fatal ALS-like disease. Here, we explored whether mutant hSOD1 aggregates with prion-like properties also exist in human ALS. Aggregate seeds were prepared from spinal cords from an ALS patient carrying the hSOD1G127Gfs*7 truncation mutation and from mice transgenic for the same mutation. To separate from mono-, di- or any oligomeric hSOD1 species, the seed preparation protocol included ultracentrifugation through a density cushion. The core structure of hSOD1G127Gfs*7 aggregates present in mice was strain A-like. Inoculation of the patient- or mouse-derived seeds into lumbar spinal cord of adult hSOD1-expressing mice induced strain A aggregation propagating along the neuraxis and premature fatal ALS-like disease (p < 0.0001). Inoculation of human or murine control seeds had no effect. The potencies of the ALS patient-derived seed preparations were high and disease was initiated in the transgenic mice by levels of hSOD1G127Gfs*7 aggregates much lower than those found in the motor system of patients carrying the mutation. The results suggest that prion-like growth and spread of hSOD1 aggregation could be the primary pathogenic mechanism, not only in hSOD1 transgenic rodent models, but also in human ALS.


Assuntos
Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/patologia , Mutação/genética , Agregados Proteicos/fisiologia , Medula Espinal/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Idoso , Animais , Mapeamento de Epitopos , Feminino , Proteína Glial Fibrilar Ácida/metabolismo , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Medula Espinal/patologia , Superóxido Dismutase/química
3.
Proc Natl Acad Sci U S A ; 112(14): 4489-94, 2015 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-25802384

RESUMO

Despite considerable progress in uncovering the molecular details of protein aggregation in vitro, the cause and mechanism of protein-aggregation disease remain poorly understood. One reason is that the amount of pathological aggregates in neural tissue is exceedingly low, precluding examination by conventional approaches. We present here a method for determination of the structure and quantity of aggregates in small tissue samples, circumventing the above problem. The method is based on binary epitope mapping using anti-peptide antibodies. We assessed the usefulness and versatility of the method in mice modeling the neurodegenerative disease amyotrophic lateral sclerosis, which accumulate intracellular aggregates of superoxide dismutase-1. Two strains of aggregates were identified with different structural architectures, molecular properties, and growth kinetics. Both were different from superoxide dismutase-1 aggregates generated in vitro under a variety of conditions. The strains, which seem kinetically under fragmentation control, are associated with different disease progressions, complying with and adding detail to the growing evidence that seeding, infectivity, and strain dependence are unifying principles of neurodegenerative disease.


Assuntos
Mapeamento de Epitopos/métodos , Proteínas/química , Superóxido Dismutase/genética , Sequência de Aminoácidos , Esclerose Lateral Amiotrófica/genética , Animais , Encéfalo/metabolismo , Epitopos/química , Humanos , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , Doenças Neurodegenerativas/metabolismo , Conformação Proteica , Dobramento de Proteína , Multimerização Proteica , Medula Espinal/metabolismo , Superóxido Dismutase/química , Superóxido Dismutase-1
4.
Oecologia ; 185(2): 317-326, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28884383

RESUMO

Plant growth in northern forest ecosystems is considered to be primarily nitrogen limited. Nitrogen deposition is predicted to change this towards co-limitation/limitation by other nutrients (e.g., phosphorus), although evidence of such stoichiometric effects is scarce. We utilized two forest fertilization experiments in southern Sweden to analyze single and combined effects of nitrogen and phosphorus on the productivity, composition, and diversity of the ground vegetation. Our results indicate that the productivity of forest ground vegetation in southern Sweden is co-limited by nitrogen and phosphorus. Additionally, the combined effect of nitrogen and phosphorus on the productivity was larger than when applied solely. No effects on species richness of any of these two nutrients were observed when applied separately, while applied in combination, they increased species richness and changed species composition, mainly by promoting more mesotrophic species. All these effects, however, occurred only for the vascular plants and not for bryophytes. The tree layer in a forest has a profound impact on the productivity and diversity of the ground vegetation by competing for both light and nutrients. This was confirmed in our study where a combination of nitrogen and high tree basal area reduced cover of the ground vegetation compared to all the other treatments where basal area was lower after stand thinning. During the past decades, nitrogen deposition may have further increased this competition from the trees for phosphorus and gradually reduced ground vegetation diversity. Phosphorus limitation induced by nitrogen deposition may, thus, contribute to ongoing changes in forest ground vegetation.


Assuntos
Biodiversidade , Florestas , Nitrogênio/metabolismo , Fósforo/metabolismo , Árvores/crescimento & desenvolvimento , Poluentes Ambientais/análise , Poluentes Ambientais/metabolismo , Atividades Humanas , Nitrogênio/análise , Fósforo/análise , Suécia
5.
Hum Mol Genet ; 22(1): 51-60, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23026746

RESUMO

A common cause of amyotrophic lateral sclerosis (ALS) is mutations in the gene encoding superoxide dismutase-1. There is evolving circumstantial evidence that the wild-type protein can also be neurotoxic and that it may more generally be involved in the pathogenesis of ALS. To test this proposition more directly, we generated mice that express wild-type human superoxide dismutase-1 at a rate close to that of mutant superoxide dismutase-1 in the commonly studied G93A transgenic model. These mice developed an ALS-like syndrome and became terminally ill after around 370 days. The loss of spinal ventral neurons was similar to that in the G93A and other mutant superoxide dismutase-1 models, and large amounts of aggregated superoxide dismutase-1 were found in spinal cords, but also in the brain. The findings show that wild-type human superoxide dismutase-1 has the ability to cause ALS in mice, and they support the hypothesis of a more general involvement of the protein in the disease in humans.


Assuntos
Esclerose Lateral Amiotrófica/genética , Superóxido Dismutase/genética , Esclerose Lateral Amiotrófica/enzimologia , Animais , Sequência de Bases , Northern Blotting , Western Blotting , Primers do DNA , Humanos , Camundongos , Camundongos Transgênicos , Reação em Cadeia da Polimerase , Medula Espinal/enzimologia , Superóxido Dismutase-1
6.
Cancer Immunol Immunother ; 64(7): 831-42, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25863943

RESUMO

Dendritic cell (DC) vaccination has demonstrated potential in clinical trials as a new effective cancer treatment, but objective and durable clinical responses are confined to a minority of patients. Interferon (IFN)-α, a type-I IFN, can bolster anti-tumor immunity by restoring or increasing the function of DCs, T cells and natural killer (NK) cells. Moreover, type-I IFN signaling on DCs was found to be essential in mice for tumor rejection by the innate and adaptive immune system. Targeted delivery of IFN-α by DCs to immune cells could boost the generation of anti-tumor immunity, while avoiding the side effects frequently associated with systemic administration. Naturally circulating plasmacytoid DCs, major producers of type-I IFN, were already shown capable of inducing tumor antigen-specific T cell responses in cancer patients without severe toxicity, but their limited number complicates their use in cancer vaccination. In the present work, we hypothesized that engineering easily generated human monocyte-derived mature DCs to secrete IFN-α using mRNA electroporation enhances their ability to promote adaptive and innate anti-tumor immunity. Our results show that IFN-α mRNA electroporation of DCs significantly increases the stimulation of tumor antigen-specific cytotoxic T cell as well as anti-tumor NK cell effector functions in vitro through high levels of IFN-α secretion. Altogether, our findings mark IFN-α mRNA-electroporated DCs as potent inducers of both adaptive and innate anti-tumor immunity and pave the way for clinical trial evaluation in cancer patients.


Assuntos
Antígenos de Neoplasias/imunologia , Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/imunologia , Interferon-alfa/metabolismo , Proteínas WT1/imunologia , Antígenos de Neoplasias/genética , Linfócitos T CD4-Positivos/imunologia , Proliferação de Células/genética , Células Cultivadas , Células Dendríticas/citologia , Células Dendríticas/transplante , Eletroporação , Humanos , Imunoterapia Adotiva , Interferon-alfa/genética , Células Matadoras Naturais/imunologia , Ativação Linfocitária/imunologia , Neoplasias/imunologia , RNA Mensageiro/administração & dosagem , RNA Mensageiro/genética , Proteínas WT1/genética
7.
J Cell Mol Med ; 18(7): 1372-80, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24979331

RESUMO

Cervarix™ is approved as a preventive vaccine against infection with the human papillomavirus (HPV) strains 16 and 18, which are causally related to the development of cervical cancer. We are the first to investigate in vitro the effects of this HPV vaccine on interleukin (IL)-15 dendritic cells (DC) as proxy of a naturally occurring subset of blood DC, and natural killer (NK) cells, two innate immune cell types that play an important role in antitumour immunity. Our results show that exposure of IL-15 DC to the HPV vaccine results in increased expression of phenotypic maturation markers, pro-inflammatory cytokine production and cytotoxic activity against HPV-positive tumour cells. These effects are mediated by the vaccine adjuvant, partly through Toll-like receptor 4 activation. Next, we demonstrate that vaccine-exposed IL-15 DC in turn induce phenotypic activation of NK cells, resulting in a synergistic cytotoxic action against HPV-infected tumour cells. Our study thus identifies a novel mode of action of the HPV vaccine in boosting innate immunity, including killing of HPV-infected cells by DC and NK cells.


Assuntos
Células Dendríticas/imunologia , Células Matadoras Naturais/imunologia , Papillomaviridae/imunologia , Infecções por Papillomavirus/imunologia , Vacinas contra Papillomavirus/uso terapêutico , Linfócitos T Citotóxicos/imunologia , Neoplasias do Colo do Útero/imunologia , Células Cultivadas , Células Dendríticas/metabolismo , Células Dendríticas/patologia , Feminino , Humanos , Imunidade Inata/imunologia , Imunofenotipagem , Interleucina-15/imunologia , Interleucina-15/metabolismo , Células Matadoras Naturais/metabolismo , Células Matadoras Naturais/patologia , Linfócitos/imunologia , Linfócitos/metabolismo , Linfócitos/patologia , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/prevenção & controle , Linfócitos T Citotóxicos/metabolismo , Linfócitos T Citotóxicos/patologia , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/prevenção & controle
8.
Cell Rep ; 43(4): 114062, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38588339

RESUMO

The role of T cell receptor (TCR) diversity in infectious disease susceptibility is not well understood. We use a systems immunology approach on three cohorts of herpes zoster (HZ) patients and controls to investigate whether TCR diversity against varicella-zoster virus (VZV) influences the risk of HZ. We show that CD4+ T cell TCR diversity against VZV glycoprotein E (gE) and immediate early 63 protein (IE63) after 1-week culture is more restricted in HZ patients. Single-cell RNA and TCR sequencing of VZV-specific T cells shows that T cell activation pathways are significantly decreased after stimulation with VZV peptides in convalescent HZ patients. TCR clustering indicates that TCRs from HZ patients co-cluster more often together than TCRs from controls. Collectively, our results suggest that not only lower VZV-specific TCR diversity but also reduced functional TCR affinity for VZV-specific proteins in HZ patients leads to lower T cell activation and consequently affects the susceptibility for viral reactivation.


Assuntos
Herpes Zoster , Herpesvirus Humano 3 , Ativação Linfocitária , Receptores de Antígenos de Linfócitos T , Humanos , Herpes Zoster/imunologia , Herpes Zoster/virologia , Receptores de Antígenos de Linfócitos T/metabolismo , Receptores de Antígenos de Linfócitos T/imunologia , Ativação Linfocitária/imunologia , Herpesvirus Humano 3/imunologia , Feminino , Pessoa de Meia-Idade , Masculino , Linfócitos T CD4-Positivos/imunologia , Idoso , Adulto , Epitopos de Linfócito T/imunologia
9.
Chemistry ; 17(32): 8832-40, 2011 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-21755546

RESUMO

C2 and C3 alkanes are selectively adsorbed from mixtures over the corresponding alkenes on the zeolite imidazolate framework ZIF-7 through a gate-opening mechanism. As a result, the direct production of the pure alkene upon adsorption and the pure alkane upon desorption in packed columns is possible. Herein, a detailed investigation of the step-wise adsorption and separation of alkanes and alkenes is presented, together with a rigorous performance assessment. A molecular picture of the gate-opening mechanism underlying the unprecedented selectivity towards alkane adsorption is proposed based on DFT calculations and a thermodynamic analysis of the adsorption-desorption isotherms.

10.
Ambio ; 40(5): 521-7, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21848140

RESUMO

Repeated fertilization of forests to increase biomass production is an environmentally controversial proposal, the effects of which we assessed on breeding birds in stands of young Norway spruce (Picea abies), in an intensively managed forest area in southern Sweden. Our results show that fertilized stands had 38% more species and 21% more individuals than unfertilized stands. Compared with stands under traditional management, the further intensification of forestry by repeated applications of fertilizers thus seemed to enhance species richness and abundance of forest birds. We cannot conclude at this stage whether the response in the bird community was caused by changes in food resources or increased structural complexity in the forest canopy due to the skid roads used for the application of the fertilizers. Future studies should focus on structural and compositional effects of fertilization processes during the entire rotation period and at assessing its effects in a landscape


Assuntos
Aves/classificação , Fertilizantes , Picea , Árvores , Animais , Biodiversidade
11.
J Am Chem Soc ; 132(50): 17704-6, 2010 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-21114318

RESUMO

Ethane is selectively adsorbed over ethylene in their mixtures on the zeolite imidazolate framework ZIF-7. In packed columns, this results in the direct production of pure ethylene. This gas-phase separation is attributed to a gate-opening effect in which specific threshold pressures control the uptake and release of individual molecules. These threshold pressures differ for the different molecules, leaving a window of selective uptake operation. This phenomenon makes ZIF-7 a perfect candidate for the separation of olefins from paraffins, since in contrast to most microporous materials, the paraffin is selectively adsorbed. Mixture adsorption, as studied by breakthrough experiments, demonstrates that gate-opening effects can be effectively used to separate molecules of very similar size.

12.
J Oral Maxillofac Surg ; 66(7): 1426-38, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18571027

RESUMO

PURPOSE: To investigate the prevalence of anatomical and surgical findings and complications in maxillary sinus floor elevation surgery, and to describe the clinical implications. PATIENTS AND METHODS: One hundred consecutive patients scheduled for maxillary sinus floor elevation were included. The patients consisted of 36 men (36%) and 64 women (64%), with a mean age of 50 years (range, 17 to 73 years). In 18 patients, a bilateral procedure was performed. Patients were treated with a top hinge door in the lateral maxillary sinus wall, as described by Tatum (Dent Clin North Am 30:207, 1986). In bilateral cases, only the first site treated was evaluated. RESULTS: In most cases, an anatomical or surgical finding forced a deviation from Tatum's standard procedure. A thin or thick lateral maxillary sinus wall was found in 78% and 4% of patients, respectively. In 6%, a strong convexity of the lateral sinus wall called for an alternative method of releasing the trapdoor. The same method was used in 4% of cases involving a narrow sinus. The sinus floor elevation procedure was hindered by septa in 48%. In regard to complications, the most common complication, a perforation of the Schneiderian membrane, occurred in 11% of patients. In 2%, visualization of the trapdoor preparation was compromised because of hemorrhages. The initial incision design, ie, slightly palatal, was responsible for a local dehiscence in 3%. CONCLUSION: To avoid unnecessary surgical complications, detailed knowledge and timely identification of the anatomic structures inherent to the maxillary sinus are required.


Assuntos
Implantação Dentária Endóssea , Seio Maxilar/anatomia & histologia , Seio Maxilar/cirurgia , Procedimentos Cirúrgicos Pré-Protéticos Bucais/efeitos adversos , Procedimentos Cirúrgicos Pré-Protéticos Bucais/métodos , Adolescente , Adulto , Idoso , Perda Sanguínea Cirúrgica , Feminino , Humanos , Masculino , Sinusite Maxilar/etiologia , Pessoa de Meia-Idade , Mucosa Nasal/lesões , Estudos Prospectivos , Deiscência da Ferida Operatória
13.
Front Immunol ; 9: 394, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29599770

RESUMO

Two decades of clinical cancer research with dendritic cell (DC)-based vaccination have proved that this type of personalized medicine is safe and has the capacity to improve survival, but monotherapy is unlikely to cure the cancer. Designed to empower the patient's antitumor immunity, huge research efforts are set to improve the efficacy of next-generation DC vaccines and to find synergistic combinations with existing cancer therapies. Immune checkpoint approaches, aiming to breach immune suppression and evasion to reinforce antitumor immunity, have been a revelation in the immunotherapy field. Early success of therapeutic antibodies blocking the programmed death-1 (PD-1) pathway has sparked the development of novel inhibitors and combination therapies. Hence, merging immunoregulatory tumor-specific DC strategies with PD-1-targeted approaches is a promising path to explore. In this review, we focus on the role of PD-1-signaling in DC-mediated antitumor immunity. In the quest of exploiting the full potential of DC therapy, different strategies to leverage DC immunopotency by impeding PD-1-mediated immune regulation are discussed, including the most advanced research on targeted therapeutic antibodies, lessons learned from chemotherapy-induced immune activation, and more recent developments with soluble molecules and gene-silencing techniques. An overview of DC/PD-1 immunotherapy combinations that are currently under preclinical and clinical investigation substantiates the clinical potential of such combination strategies.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Vacinas Anticâncer/imunologia , Células Dendríticas/transplante , Imunoterapia/métodos , Neoplasias/terapia , Animais , Terapia Combinada , Células Dendríticas/imunologia , Avaliação Pré-Clínica de Medicamentos , Humanos , Neoplasias/imunologia , Receptor de Morte Celular Programada 1/imunologia
14.
Oncotarget ; 9(45): 27797-27808, 2018 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-29963238

RESUMO

Blockade of programmed cell death protein 1 (PD-1) immune checkpoint receptor signaling is an established standard treatment for many types of cancer and indications are expanding. Successful clinical trials using monoclonal antibodies targeting PD-1 signaling have boosted preclinical research, encouraging development of novel therapeutics. Standardized assays to evaluate their bioactivity, however, remain restricted. The robust bioassays available all lack antigen-specificity. Here, we developed an antigen-specific, short-term and high-throughput T cell assay with versatile readout possibilities. A genetically modified T cell receptor (TCR)-deficient T cell line was stably transduced with PD-1. Transfection with messenger RNA encoding a TCR of interest and subsequent overnight stimulation with antigen-presenting cells, results in eGFP-positive and granzyme B-producing T cells for single cell or bulk analysis. Control antigen-presenting cells induced reproducible high antigen-specific eGFP and granzyme B expression. Upon PD-1 interaction, ligand-positive antigen-presenting immune or tumor cells elicited significantly lower eGFP and granzyme B expression, which could be restored by anti-PD-(L)1 blocking antibodies. This convenient cell-based assay shows a valuable tool for translational and clinical research on antigen-specific checkpoint-targeted therapy approaches.

15.
Front Immunol ; 9: 2503, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30464762

RESUMO

Genetic engineering of T cells with tumor specific T-cell receptors (TCR) is a promising strategy to redirect their specificity against cancer cells in adoptive T cell therapy protocols. Most studies are exploiting integrating retro- or lentiviral vectors to permanently introduce the therapeutic TCR, which can pose serious safety issues when treatment-related toxicities would occur. Therefore, we developed a versatile, non-genotoxic transfection method for human unstimulated CD8+ T cells. We describe an optimized double sequential electroporation platform whereby Dicer-substrate small interfering RNAs (DsiRNA) are first introduced to suppress endogenous TCR α and ß expression, followed by electroporation with DsiRNA-resistant tumor-specific TCR mRNA. We demonstrate that double sequential electroporation of human primary unstimulated T cells with DsiRNA and TCR mRNA leads to unprecedented levels of transgene TCR expression due to a strongly reduced degree of TCR mispairing. Importantly, superior transgenic TCR expression boosts epitope-specific CD8+ T cell activation and killing activity. Altogether, DsiRNA and TCR mRNA double sequential electroporation is a rapid, non-integrating and highly efficient approach with an enhanced biosafety profile to engineer T cells with antigen-specific TCRs for use in early phase clinical trials.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Engenharia Genética/métodos , Imunoterapia Adotiva/métodos , Neoplasias/terapia , RNA/genética , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Antígenos de Neoplasias/imunologia , Linfócitos T CD8-Positivos/transplante , Citotoxicidade Imunológica , Eletroporação , Epitopos de Linfócito T/imunologia , Vetores Genéticos , Humanos , Neoplasias/imunologia , RNA Interferente Pequeno/genética , Ribonuclease III/metabolismo , Especificidade do Receptor de Antígeno de Linfócitos T
16.
Oncoimmunology ; 7(3): e1407899, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29399410

RESUMO

Prognosis of glioblastoma remains dismal, underscoring the need for novel therapies. Immunotherapy is generating promising results, but requires combination strategies to unlock its full potential. We investigated the immunomodulatory capacities of poly(I:C) on primary human glioblastoma cells and its combinatorial potential with programmed death ligand (PD-L) blockade. In our experiments, poly(I:C) stimulated expression of both PD-L1 and PD-L2 on glioblastoma cells, and a pro-inflammatory secretome, including type I interferons (IFN) and chemokines CXCL9, CXCL10, CCL4 and CCL5. IFN-ß was partially responsible for the elevated PD-1 ligand expression on these cells. Moreover, real-time PCR and chloroquine-mediated blocking experiments indicated that poly(I:C) triggered Toll-like receptor 3 to elicit its effect. Cocultures of poly(I:C)-treated glioblastoma cells with peripheral blood mononuclear cells enhanced lymphocytic activation (CD69, IFN-γ) and cytotoxic capacity (CD107a, granzyme B). Additional PD-L1 blockade further propagated immune activation. Besides activating immunity, poly(I:C)-treated glioblastoma cells also doubled the attraction of CD8+ T cells, and to a lesser extent CD4+ T cells, via a mechanism which included CXCR3 and CCR5 ligands. Our results indicate that by triggering glioblastoma cells, poly(I:C) primes the tumor microenvironment for an immune response. Secreted cytokines allow for immune activation while chemokines attract CD8+ T cells to the front, which are postulated as a prerequisite for effective PD-1/PD-L1 blockade. Accordingly, additional blockade of the concurrently elevated tumoral PD-L1 further reinforces the immune activation. In conclusion, our data proposes poly(I:C) treatment combined with PD-L1 blockade to invigorate the immune checkpoint inhibition response in glioblastoma.

17.
Ind Eng Chem Res ; 56(45): 13423-13433, 2017 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-29170600

RESUMO

ZnCl2 hydrate, the main molten salt used in biomass conversion, combined with low concentration HCl is an excellent solvent for the dissolution and hydrolysis of the carbohydrates present in lignocellulosic biomass. The most recalcitrant carbohydrate, cellulose, is dissolved in a residence time less than 1 h under mild conditions without significant degradation. This technology is referred to as BIOeCON-solvent technology. Separation of the sugars from the solution is the main challenge. The earlier conclusion regarding the potential of zeolite beta for selective adsorption has been used as the basis of a scale-up study. The technology of choice is continuous chromatographic separation (e.g., simulated moving bed, SMB). The sugar monomers are separated from the sugar oligomers, allowing the production of monosugars at high yield, using water as an eluent. Results of a pilot plant study are presented showing a stable operation at high selectivity. Several process designs are discussed, and the techno-economic performance of the BIOeCON-solvent technology is demonstrated by comparison with the state-of-the-art technology of NREL (National Renewable Energy Laboratory), which is based on enzymatic conversion of cellulose. It is concluded that the BIOeCON-solvent technology is technically and economically viable and is competitive to the NREL process. Because the BIOeCON-solvent process is in an early stage of development and far from fully optimized, it has the potential to outperform the existing processes.

18.
Pharmacol Ther ; 170: 73-79, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27777088

RESUMO

Interleukin (IL)-15 as a stand-alone therapy can activate the antitumor functions of immune effector cells resulting in significant tumor regression. Interestingly, combining IL-15 with the α-moiety of its receptor (IL-15Rα), also called IL-15 transpresentation, increases the in vivo half-life of IL-15 and enhances binding of IL-15 with cells expressing the IL-15Rßγ, such as NK cells and CD8+ T cells. These features enlarge the signal transmission of IL-15, resulting in improved proliferation and antitumor activities of both NK cells and CD8+ T cells, eventually leading to enhanced killing of tumor cells. In this review, we discuss the antitumor strategies in which this IL-15 transpresentation mechanism is implemented, that are currently under preclinical investigation. Furthermore, we give an overview of the studies in which the IL-15/IL-15Rα complexes are combined with other antitumor therapies. The promising results in these preclinical studies have incited several clinical trials to test the safety and efficacy of IL-15 transpresentation strategies to treat both hematological and advanced solid tumors.


Assuntos
Subunidade alfa de Receptor de Interleucina-15/imunologia , Interleucina-15/administração & dosagem , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/imunologia , Linfócitos T CD8-Positivos/imunologia , Neoplasias Hematológicas/tratamento farmacológico , Neoplasias Hematológicas/imunologia , Humanos , Interleucina-15/imunologia , Células Matadoras Naturais/imunologia , Neoplasias/imunologia , Neoplasias/patologia
19.
Front Immunol ; 8: 1964, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29403473

RESUMO

The use of tolerance-inducing dendritic cells (tolDCs) has been proven to be safe and well tolerated in the treatment of autoimmune diseases. Nevertheless, several challenges remain, including finding ways to facilitate the migration of cell therapeutic products to lymph nodes, and the site of inflammation. In the treatment of neuroinflammatory diseases, such as multiple sclerosis (MS), the blood-brain barrier (BBB) represents a major obstacle to the delivery of therapeutic agents to the inflamed central nervous system (CNS). As it was previously demonstrated that C-C chemokine receptor 5 (CCR5) may be involved in inflammatory migration of DCs, the aim of this study was to investigate CCR5-driven migration of tolDCs. Only a minority of in vitro generated vitamin D3 (vitD3)-treated tolDCs expressed the inflammatory chemokine receptor CCR5. Thus, messenger RNA (mRNA) encoding CCR5 was introduced by means of electroporation (EP). After mRNA EP, tolDCs transiently displayed increased levels of CCR5 protein expression. Accordingly, the capacity of mRNA electroporated tolDCs to transmigrate toward a chemokine gradient in an in vitro model of the BBB improved significantly. Neither the tolerogenic phenotype nor the T cell-stimulatory function of tolDCs was affected by mRNA EP. EP of tolDCs with mRNA encoding CCR5 enabled these cells to migrate to inflammatory sites. The approach used herein has important implications for the treatment of MS. Using this approach, tolDCs actively shuttle across the BBB, allowing in situ down-modulation of autoimmune responses in the CNS.

20.
Oncotarget ; 8(34): 56968-56979, 2017 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-28915646

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is the 4th leading cause of cancer-related death in Western countries with a 5-year survival rate below 5%. One of the hallmarks of this cancer is the strong desmoplastic reaction within the tumor microenvironment (TME), orchestrated by activated pancreatic stellate cells (PSC). This results in a functional and mechanical shield which causes resistance to conventional therapies. Aiming to overcome this resistance by tackling the stromal shield, we assessed for the first time the capacity of IL-15 stimulated natural killer (NK) cells to kill PSC and pancreatic cancer cells (PCC). The potency of IL-15 to promote NK cell-mediated killing was evaluated phenotypically and functionally. In addition, NK cell and immune checkpoint ligands on PSC were charted. We demonstrate that IL-15 activated NK cells kill both PCC and PSC lines (range 9-35% and 20-50%, respectively) in a contact-dependent manner and significantly higher as compared to resting NK cells. Improved killing of these pancreatic cell lines is, at least partly, dependent on IL-15 induced upregulation of TIM-3 and NKG2D. Furthermore, we confirm significant killing of primary PSC by IL-15 activated NK cells in an ex vivo autologous system. Screening for potential targets for immunotherapeutic strategies, we demonstrate surface expression of both inhibitory (PD-L1, PD-L2) and activating (MICA/B, ULBPs and Galectin-9) ligands on primary PSC. These data underscore the therapeutic potential of IL-15 to promote NK cell-mediated cytotoxicity as a treatment of pancreatic cancer and provide promising future targets to tackle remaining PSC.

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