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1.
Proc Natl Acad Sci U S A ; 121(24): e2400145121, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38833465

RESUMO

Microalgae are promising production platforms for the cost-effective production of recombinant proteins. We have recently established that the red alga Porphyridium purpureum provides superior transgene expression properties, due to the episomal maintenance of transformation vectors as multicopy plasmids in the nucleus. Here, we have explored the potential of Porphyridium to synthesize complex pharmaceutical proteins to high levels. Testing expression constructs for a candidate subunit vaccine against the hepatitis C virus (HCV), we show that the soluble HCV E2 glycoprotein can be produced in transgenic algal cultures to high levels. The antigen undergoes faithful posttranslational modification by N-glycosylation and is recognized by conformationally selective antibodies, suggesting that it adopts a proper antigenic conformation in the endoplasmic reticulum of red algal cells. We also report the experimental determination of the structure of the N-glycan moiety that is attached to glycosylated proteins in Porphyridium. Finally, we demonstrate the immunogenicity of the HCV antigen produced in red algae when administered by injection as pure protein or by feeding of algal biomass.


Assuntos
Hepacivirus , Porphyridium , Porphyridium/metabolismo , Porphyridium/imunologia , Porphyridium/genética , Hepacivirus/imunologia , Hepacivirus/genética , Glicosilação , Proteínas do Envelope Viral/imunologia , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/metabolismo , Animais
2.
Plant Biotechnol J ; 21(6): 1176-1190, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36779605

RESUMO

The recent SARS-CoV-2 pandemic has taught the world a costly lesson about the devastating consequences of viral disease outbreaks but also, the remarkable impact of vaccination in limiting life and economic losses. Vaccination against human Hepatitis B Virus (HBV), a major human pathogen affecting 290 million people worldwide, remains a key action towards viral hepatitis elimination by 2030. To meet this goal, the development of improved HBV antigens is critical to overcome non-responsiveness to standard vaccines based on the yeast-produced, small (S) envelope protein. We have recently shown that combining relevant immunogenic determinants of S and large (L) HBV proteins in chimeric antigens markedly enhances the anti-HBV immune response. However, the demand for cost-efficient, high-quality antigens remains challenging. This issue could be addressed by using plants as versatile and rapidly scalable protein production platforms. Moreover, the recent generation of plants lacking ß-1,2-xylosyltransferase and α-1,3-fucosyltransferase activities (FX-KO), by CRISPR/Cas9 genome editing, enables production of proteins with "humanized" N-glycosylation. In this study, we investigated the impact of plant N-glycosylation on the immunogenic properties of a chimeric HBV S/L vaccine candidate produced in wild-type and FX-KO Nicotiana benthamiana. Prevention of ß-1,2-xylose and α-1,3-fucose attachment to the HBV antigen significantly increased the immune response in mice, as compared with the wild-type plant-produced counterpart. Notably, the antibodies triggered by the FX-KO-made antigen neutralized more efficiently both wild-type HBV and a clinically relevant vaccine escape mutant. Our study validates in premiere the glyco-engineered Nicotiana benthamiana as a substantially improved host for plant production of glycoprotein vaccines.


Assuntos
COVID-19 , Vírus da Hepatite B , Humanos , Animais , Camundongos , Vírus da Hepatite B/genética , Glicosilação , Nicotiana/genética , Sistemas CRISPR-Cas/genética , COVID-19/genética , SARS-CoV-2 , Vacinas contra Hepatite B/genética , Anticorpos Neutralizantes , Antígenos de Superfície da Hepatite B/genética
3.
Micromachines (Basel) ; 13(11)2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36363854

RESUMO

This study proposes a feasible approach for the rapid, sensitive, and label-free identification of cancerous cells based on dielectrophoretic (DEP) manipulation and electrical characterization. In this method, the concentration of target cells at the level of customized microelectrodes via DEP is first determined, followed by an electrical impedance evaluation. The study demonstrates the capacity of the methodology to electrically differentiate HT-29 cancer cells from healthy blood cells based on their impedance spectra. Within a higher frequency domain, the electrical impedance of trapped cancer cells was significantly lower compared with the normal ones. In order to evaluate the functionality and reproducibility of the proposed method, the influence of the DEP and EIS (electrical impedance spectroscopy) operating voltages on the electrical characterization of trapped HT-29 cells was analyzed.

4.
Front Immunol ; 13: 941243, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35935966

RESUMO

Despite the availability of improved antiviral therapies, infection with Hepatitis B virus (HBV) remains a3 significant health issue, as a curable treatment is yet to be discovered. Current HBV vaccines relaying on the efficient expression of the small (S) envelope protein in yeast and the implementation of mass vaccination programs have clearly contributed to containment of the disease. However, the lack of an efficient immune response in up to 10% of vaccinated adults, the controversies regarding the seroprotection persistence in vaccine responders and the emergence of vaccine escape virus mutations urge for the development of better HBV immunogens. Due to the critical role played by the preS1 domain of the large (L) envelope protein in HBV infection and its ability to trigger virus neutralizing antibodies, including this protein in novel vaccine formulations has been considered a promising strategy to overcome the limitations of S only-based vaccines. In this work we aimed to combine relevant L and S epitopes in chimeric antigens, by inserting preS1 sequences within the external antigenic loop of S, followed by production in mammalian cells and detailed analysis of their antigenic and immunogenic properties. Of the newly designed antigens, the S/preS116-42 protein assembled in subviral particles (SVP) showed the highest expression and secretion levels, therefore, it was selected for further studies in vivo. Analysis of the immune response induced in mice vaccinated with S/preS116-42- and S-SVPs, respectively, demonstrated enhanced immunogenicity of the former and its ability to activate both humoral and cellular immune responses. This combined activation resulted in production of neutralizing antibodies against both wild-type and vaccine-escape HBV variants. Our results validate the design of chimeric HBV antigens and promote the novel S/preS1 protein as a potential vaccine candidate for administration in poor-responders to current HBV vaccines.


Assuntos
Antígenos de Superfície da Hepatite B , Vírus da Hepatite B , Animais , Anticorpos Bloqueadores , Anticorpos Neutralizantes , Vacinas contra Hepatite B , Imunidade Humoral , Mamíferos , Camundongos , Camundongos Endogâmicos BALB C , Vacinas Sintéticas
5.
Biosensors (Basel) ; 11(10)2021 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-34677357

RESUMO

Here, we reported a study on the detection and electrical characterization of both cancer cell line and primary tumor cells. Dielectrophoresis (DEP) and electrical impedance spectroscopy (EIS) were jointly employed to enable the rapid and label-free differentiation of various cancer cells from normal ones. The primary tumor cells that were collected from two colorectal cancer patients, cancer cell lines (SW-403, Jurkat, and THP-1), and healthy peripheral blood mononuclear cells (PBMCs) were trapped first at the level of interdigitated microelectrodes with the help of dielectrophoresis. Correlation of the cells dielectric characteristics that was obtained via electrical impedance spectroscopy (EIS) allowed evident differentiation of the various types of cell. The differentiations were assigned to a "dielectric phenotype" based on their crossover frequencies. Finally, Randles equivalent circuit model was employed for highlighting the differences with regard to a series group of charge transport resistance and constant phase element for cancerous and normal cells.


Assuntos
Espectroscopia Dielétrica , Leucócitos Mononucleares , Diferenciação Celular , Impedância Elétrica , Humanos , Fenótipo
6.
Plant Biotechnol J ; 19(10): 2027-2039, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34002936

RESUMO

Chronic infection with hepatitis C virus (HCV) remains a leading cause of liver-related pathologies and a global health problem, currently affecting more than 71 million people worldwide. The development of a prophylactic vaccine is much needed to complement the effective antiviral treatment available and achieve HCV eradication. Current strategies focus on increasing the immunogenicity of the HCV envelope glycoprotein E2, the major target of virus-neutralizing antibodies, by testing various expression systems or manipulating the protein conformation and the N-glycosylation pattern. Here we report the first evidence of successful production of the full-length HCV E2 glycoprotein in Nicotiana benthamiana, by using the Agrobacterium-mediated transient expression technology. Molecular and functional analysis showed that the viral protein was correctly processed in plant cells and achieved the native folding required for binding to CD81, one of the HCV receptors. N-glycan analysis of HCV-E2 produced in N. benthamiana and mammalian cells indicated host-specific trimming of mannose residues and possibly, protein trafficking. Notably, the plant-derived viral antigen triggered a significant immune response in vaccinated mice, characterized by the presence of antibodies with HCV-neutralizing activity. Together, our study demonstrates that N. benthamiana is a viable alternative to costly mammalian cell cultures for the expression of complex viral antigens and supports the use of plants as cost-effective production platforms for the development of HCV vaccines.


Assuntos
Hepacivirus , Vacinas contra Hepatite Viral , Animais , Anticorpos Neutralizantes , Anticorpos Anti-Hepatite C , Camundongos , Nicotiana , Proteínas do Envelope Viral/genética
7.
Exp Ther Med ; 20(3): 2352-2360, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32765714

RESUMO

Allergic diseases have been classified in the last decades using various theories. The main classes of the newest classification in allergic respiratory diseases focus on the characterization of the endotype (which takes into account biomarkers related to determinant pathophysiological mechanisms) and of the phenotype (based on the description of the disease). Th2, Th1 and Th17 lymphocytes and the type of inflammatory response mediated by them represent the basis for Th2 and non-Th2 endotype classification. In addition, new lymphocytes were also used to characterize allergic diseases: Th9 lymphocytes, Th22 lymphocytes, T follicular helper cells (TFH) lymphocytes and invariant natural killer T (iNKT) lymphocytes. In the last decade, a growing body of evidence focused on chemokines, chemoattractant cytokines, which seems to have an important contribution to the pathogenesis of this pathology. This review presents the interactions between chemokines and Th lymphocytes in the context of Th2/non-Th2 endotype classification of respiratory allergies.

8.
Cureus ; 12(4): e7783, 2020 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-32461855

RESUMO

Background Allergic rhinitis (AR) is a chronic and frequent condition characterized by an excessive response of the immune system to innocent substances encountered in the nasal mucosa. These reactions are mediated by many factors, including chemokines. Chemokine ligand 3 (CCL3, a macrophage inflammatory protein 1α) is a chemokine implicated in the activation of mast cells - white cells shown to be highly involved in orchestrating allergic reactions. The present study evaluated the role of CCL3 in AR. Material and methods Thirty-nine participants, including 24 patients with AR and 15 healthy controls, were evaluated for allergies to dust mites, cat and dog danders, cockroaches (Blatella germanica), molds, grasses, weeds, and tree pollen using skin prick tests. Participants were also evaluated for inflammatory conditions by measuring total blood count with differential; concentrations of rheumatoid factor, fibrinogen, and C-reactive protein; and erythrocyte sedimentation rate. CCL3 in blood samples was measured at the Immunology Laboratory, Cantacuzino National Institute for Military Medical Research and Development, Bucharest, Romania, using Human Multianalyte Profiling Base Kits (R&D Systems Inc., Minneapolis, MN). Results Mean serum CCL3 concentration was significantly higher in patients with AR than in controls (15.03 ± 7.11 pg/ml vs. 8.34 ± 4.46 pg/ml, p = 0.001 [t-test] and p = 0.026 [Mann-Whitney test]). CCL3 concentrations correlated with polysensitization, defined as two or more positive prick tests per patient (r = 0.325, p = 0.046) and seasonal AR (r = 0.482, p = 0.002). Conclusions Elevated levels of CCL3 were seen in our patients with AR. We have observed correlations with polysensitization and seasonal allergies. These results suggest that chemokines might play an important role in the pathogenesis of AR. In the future, chemokines might be used in endotype classification of patients with AR and as a possible target in the treatment of AR.

9.
Vaccine ; 36(38): 5789-5795, 2018 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-30082163

RESUMO

Hepatitis B Virus (HBV) infection can be prevented by vaccination. Vaccines containing the small (S) envelope protein are currently used in universal vaccination programs and achieve protective immune response in more than 90% of recipients. However, new vaccination strategies are necessary for successful immunization of the remaining non- or low-responders. We have previously characterized a novel HBV chimeric antigen, which combines neutralization epitopes of the S and the preS1 domain of the large (L) envelope protein (genotype D). The S/preS121-47 chimera produced in mammalian cells and Nicotiana benthamiana plants, induced a significantly stronger immune response in parenterally vaccinated mice than the S protein. Here we describe the transient expression of the S/preS121-47 antigen in an edible plant, Lactuca sativa, for potential development of an oral HBV vaccine. Our study shows that oral administration of adjuvant-free Lactuca sativa expressing the S/preS121-47 antigen, three times, at 1 µg/dose, was sufficient to trigger a humoral immune response in mice. Importantly, the elicited antibodies were able to neutralize HBV infection in an NTCP-expressing infection system (HepG2-NTCP cell line) more efficiently than those induced by mice fed on Lactuca sativa expressing the S protein. These results support the S/preS121-47 antigen as a promising candidate for future development as an edible HBV vaccine.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Antígenos de Superfície da Hepatite B/imunologia , Vacinas contra Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Hepatite B/prevenção & controle , Precursores de Proteínas/imunologia , Administração Oral , Animais , Linhagem Celular Tumoral , Feminino , Células Hep G2 , Vacinas contra Hepatite B/administração & dosagem , Humanos , Lactuca/genética , Lactuca/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Recombinantes de Fusão/imunologia , Vacinação , Proteínas do Envelope Viral/imunologia
10.
J Mol Endocrinol ; 60(1): 1-15, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29247133

RESUMO

The use of mesenchymal stem cells (MSC) as a therapeutic tool in cardiovascular diseases is promising. Since androgens exert some beneficial actions on the cardiovascular system, we tested our hypothesis that this hormone could promote MSC-mediated repair processes, also. Cultured MSCs isolated from Wharton's jelly were exposed to 30 nM dihydrotestosterone (DHT) for 1 or 4 days and the effects of the hormone on their growth/migration/adhesion and the underlying mechanisms were assessed. Results were obtained by real-time cell impedance measurements, and DNA quantification showed that DHT increased MSC proliferation by ~30%. As determined by xCELLigence system, DHT augmented (~2 folds) the migration of MSC toward cardiac tissue slices (at 12 h), and this effect was blocked by flutamide, an androgen receptor (AR) antagonist. Exposure of cells to DHT, upregulated the gene and protein expression of AR, EMMPRIN and MMP-9 and downregulated the expression of MMP-2 DHT significantly induced the release of nitric oxide by MSC (≥2-fold) and flutamide blocked this effect. When MSCs were co-cultured with cardiac slices, immunohistochemical analysis and qRT-PCR showed that the integration of DHT-stimulated MSC was significantly higher than that of in controls. In conclusion, our findings provide the first evidence that DHT promotes MSC growth, migration and integration into the cardiac slices. The modulating effects of DHT were associated with upregulation of ARs and of key molecules known to promote tissue remodeling and angiogenesis. Our findings suggest that priming of MSC with DHT may potentially increase their capability to regenerate cardiac tissue; in vivo studies are needed to confirm our in vitro findings.


Assuntos
Indutores da Angiogênese/farmacologia , Di-Hidrotestosterona/farmacologia , Células-Tronco Mesenquimais/citologia , Miocárdio/citologia , Citoesqueleto de Actina/efeitos dos fármacos , Citoesqueleto de Actina/metabolismo , Animais , Basigina/genética , Basigina/metabolismo , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Cromatografia Líquida , Humanos , Espectrometria de Massas , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Camundongos , Óxido Nítrico/biossíntese , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Regulação para Cima/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/metabolismo
11.
J Mater Sci Mater Med ; 28(10): 153, 2017 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-28861646

RESUMO

Nano-apatite and gelatin-alginate hydrogel microparticles have been prepared by a one-step synthesis combined with electrostatic bead generation, for the reconstruction of bone defects. Based on the analysis of bone composition, architecture and embryonic intramembranous ossification, a bio-inspired fabrication has been developed. Accordingly, the mineral phase has been in situ synthesized, calcifying the hydrogel matrix while the latter was crosslinked, finally generating microparticles that can assemble into a bone defect to ensure interconnected pores. Although nano-apatite-biopolymer composites have been widely investigated, microstructural optimization to provide improved distribution and stability of the mineral is rarely achieved. The optimization of the developed method progressively resulted in two types of formulations (15P and 7.5P), with 15 and 7.5 (wt%) phosphate content in the initial precursor. The osteolytic potential was investigated using differentiated macrophages. A commercially available calcium phosphate bone graft substitute (Eurocer 400) was incorporated into the hydrogel, and the obtained composites were in vitro tested for comparison. The cytocompatibility of the microparticles was studied with mouse osteoblast-like cell line MC3T3-E1. Results indicated the best in vitro performance have been obtained for the sample loaded with 7.5P. Preliminary evaluation of biocompatibility into a critical size (3 mm) defect in rabbits showed that 7.5P nanocomposite is associated with newly formed bone in the proximity of the microparticles, after 28 days.


Assuntos
Regeneração Óssea , Substitutos Ósseos/química , Nanocompostos/química , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Animais , Materiais Biocompatíveis , Calcificação Fisiológica , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Lactato Desidrogenases/metabolismo , Teste de Materiais , Camundongos , Monócitos/fisiologia , Osteogênese
12.
Antiviral Res ; 144: 256-265, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28666757

RESUMO

Chronic Hepatitis B Virus (HBV) infection leads to severe liver pathogenesis associated with significant morbidity and mortality. As no curable medication is yet available, vaccination remains the most cost-effective approach to limit HBV spreading and control the infection. Although safe and efficient, the standard vaccine based on production of the small (S) envelope protein in yeast fails to elicit an effective immune response in about 10% of vaccinated individuals, which are at risk of infection. One strategy to address this issue is the development of more immunogenic antigens. Here we describe a novel HBV antigen obtained by combining relevant immunogenic determinants of S and large (L) envelope proteins. Our approach was based on the insertion of residues 21-47 of the preS1 domain of the L protein (nomenclature according to genotype D), involved in virus attachment to hepatocytes, within the external antigenic loop of S. The resulting S/preS121-47 chimera was successfully produced in HEK293T and Nicotiana benthamiana plants, as a more economical recombinant protein production platform. Comparative biochemical, functional and electron microscopy analysis indicated assembly of the novel antigen into subviral particles in mammalian and plant cells. Importantly, these particles preserve both S- and preS1-specific epitopes and elicit significantly stronger humoral and cellular immune responses than the S protein, in both expression systems used. Our data promote this antigen as a promising vaccine candidate to overcome poor responsiveness to the conventional, S protein-based, HBV vaccine.


Assuntos
Antígenos de Superfície da Hepatite B/imunologia , Vacinas contra Hepatite B/imunologia , Vacinas de Partículas Semelhantes a Vírus/imunologia , Animais , Linhagem Celular , Anticorpos Anti-Hepatite B/sangue , Antígenos de Superfície da Hepatite B/genética , Vacinas contra Hepatite B/administração & dosagem , Vacinas contra Hepatite B/genética , Vacinas contra Hepatite B/isolamento & purificação , Humanos , Interferon gama/metabolismo , Leucócitos Mononucleares/imunologia , Camundongos Endogâmicos BALB C , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Baço/imunologia , Nicotiana , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/isolamento & purificação , Vacinas de Partículas Semelhantes a Vírus/administração & dosagem , Vacinas de Partículas Semelhantes a Vírus/genética , Vacinas de Partículas Semelhantes a Vírus/isolamento & purificação
13.
Plant Biotechnol J ; 15(12): 1611-1621, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28419665

RESUMO

The hepatitis C virus (HCV) is a major etiologic agent for severe liver diseases (e.g. cirrhosis, fibrosis and hepatocellular carcinoma). Approximately 140 million people have chronic HCV infections and about 500 000 die yearly from HCV-related liver pathologies. To date, there is no licensed vaccine available to prevent HCV infection and production of a HCV vaccine remains a major challenge. Here, we report the successful production of the HCV E1E2 heterodimer, an important vaccine candidate, in an edible crop (lettuce, Lactuca sativa) using Agrobacterium-mediated transient expression technology. The wild-type dimer (E1E2) and a variant without an N-glycosylation site in the E2 polypeptide (E1E2∆N6) were expressed, and appropriate N-glycosylation pattern and functionality of the E1E2 dimers were demonstrated. The humoral immune response induced by the HCV proteins was investigated in mice following oral administration of lettuce antigens with or without previous intramuscular prime with the mammalian HEK293T cell-expressed HCV dimer. Immunization by oral feeding only resulted in development of weak serum levels of anti-HCV IgM for both antigens; however, the E1E2∆N6 proteins produced higher amounts of secretory IgA, suggesting improved immunogenic properties of the N-glycosylation mutant. The mice group receiving the intramuscular injection followed by two oral boosts with the lettuce E1E2 dimer developed a systemic but also a mucosal immune response, as demonstrated by the presence of anti-HCV secretory IgA in faeces extracts. In summary, our study demonstrates the feasibility of producing complex viral antigens in lettuce, using plant transient expression technology, with great potential for future low-cost oral vaccine development.


Assuntos
Lactuca/genética , Proteínas do Envelope Viral/imunologia , Vacinas contra Hepatite Viral/administração & dosagem , Vacinas contra Hepatite Viral/imunologia , Administração Oral , Animais , Feminino , Células HEK293 , Humanos , Imunidade Humoral , Camundongos Endogâmicos BALB C , Plantas Geneticamente Modificadas , Engenharia de Proteínas/métodos , Multimerização Proteica , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/isolamento & purificação , Proteínas do Envelope Viral/genética , Vacinas contra Hepatite Viral/genética
14.
Hum Vaccin Immunother ; 12(4): 1009-26, 2016 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-26618392

RESUMO

Millions of seasonal and pandemic influenza vaccine doses containing oil-in-water emulsion adjuvant have been administered in order to enhance and broaden immune responses and to facilitate antigen sparing. Despite the enactment of a Global Action Plan for Influenza Vaccines and a multi-fold increase in production capabilities over the past 10 years, worldwide capacity for pandemic influenza vaccine production is still limited. In developing countries, where routine influenza vaccination is not fully established, additional measures are needed to ensure adequate supply of pandemic influenza vaccines without dependence on the shipment of aid from other, potentially impacted first-world countries. Adaptation of influenza vaccine and adjuvant technologies by developing country influenza vaccine manufacturers may enable antigen sparing and corresponding increases in global influenza vaccine coverage capacity. Following on previously described work involving the technology transfer of oil-in-water emulsion adjuvant manufacturing to a Romanian vaccine manufacturing institute, we herein describe the preclinical evaluation of inactivated split virion H5N1 influenza vaccine with emulsion adjuvant, including immunogenicity, protection from virus challenge, antigen sparing capacity, and safety. In parallel with the evaluation of the bioactivity of the tech-transferred adjuvant, we also describe the impact of concurrent antigen manufacturing optimization activities. Depending on the vaccine antigen source and manufacturing process, inclusion of adjuvant was shown to enhance and broaden functional antibody titers in mouse and rabbit models, promote protection from homologous virus challenge in ferrets, and facilitate antigen sparing. Besides scientific findings, the operational lessons learned are delineated in order to facilitate adaptation of adjuvant technologies by other developing country institutes to enhance global pandemic influenza preparedness.


Assuntos
Adjuvantes Imunológicos , Virus da Influenza A Subtipo H5N1/imunologia , Vacinas contra Influenza , Transferência de Tecnologia , Avaliação Pré-Clínica de Medicamentos , Emulsões/química , Humanos , Virus da Influenza A Subtipo H5N1/fisiologia , Vacinas contra Influenza/imunologia , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Óleos , Pandemias/prevenção & controle , Romênia , Vírion/fisiologia , Inativação de Vírus
15.
Acta Histochem ; 115(8): 840-50, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23701965

RESUMO

The interactions between neurons, immune and immune-like glial cells can initiate the abnormal processes that underlie neuropathic pain. In the peripheral nervous system the resident macrophages may play an important role. In this study we investigated in experimental adult Sprague-Dawley rats how Iba-1 (ionized calcium binding adaptor molecule 1) (+) resident macrophages in the dorsal root ganglion (DRG) are activated after a spinal nerve ligation (SNL) or streptozotocin (STZ)-induced diabetes. The activation profile was defined by comparing the responses of resident macrophages against microglia in the spinal cord as they share a common origin. After SNL, the Iba-1 (+) macrophages in L5 DRG reached their activation peak 5 days later, clustered as satellite cells around large A-neurons, expressed the MHC-II marker, but did not show p-p38 and p-ERK1/2 activation and did not secrete IL-18. After STZ-induced diabetes, the Iba-1 (+) macrophages reached their activation peak 1 week later in L4 and L5 DRG, remained scattered between neurons, expressed the MHC-II marker only in L5 DRG, did not show p-p38 and p-ERK1/2 activation and did not secrete any of the investigated cytokines/chemokines. These responses suggest that depending on the type of lesion DRG Iba-1 (+) resident macrophages have different activation mechanisms, which are dissimilar to those in microglia.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Gânglios Espinais/metabolismo , Macrófagos/metabolismo , Proteínas dos Microfilamentos/metabolismo , Animais , Gânglios Espinais/patologia , Macrófagos/patologia , Masculino , Ratos , Ratos Sprague-Dawley
16.
Tumori ; 97(5): 647-54, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22158498

RESUMO

AIMS AND BACKGROUND: Macrophages are heterogeneous cells with extensive functional plasticity; they can change their functional profiles repeatedly in response to environmental changes anywhere between their extreme phenotypical programs (labeled as M1 and M2 polarization, respectively). In terms of antitumoral immune response, M1 macrophages are considered to be beneficial, while M2 macrophages supposedly promote tumor progression. Tumor-associated macrophages (TAMs) represent a major leukocyte population present in many tumors. Although many studies indicate that TAMs elicit several M2-associated protumoral functions, including promotion of angiogenesis, matrix remodeling and suppression of adaptive immunity, their role regarding tumor progression is still controversial. The aim of the present study was to develop an appropriate in vitro model to study the effect of tumor-secreted soluble factors on the functional phenotype of macrophages. METHODS AND STUDY DESIGN: THP-1 human monocytic line cells and peripheral blood mononuclear cells from healthy volunteers were used for macrophage differentiation; primary tumor cell culture supernatants or tumor cell line supernatants were employed along with various cytokines, growth factors and other stimuli to design different model variants and to better mimic the in vivo tumor microenvironment. RESULTS: The cytokine secretion patterns of these macrophages suggest that primary tumor cell culture supernatants are able to switch the macrophage phenotype or to induce functional polarization of macrophages toward a mixed M1/M2 phenotype. Conclusions. These data support the hypothesis that TAM behavior is modulated by the tumor microenvironment itself.


Assuntos
Adenocarcinoma/metabolismo , Neoplasias Colorretais/metabolismo , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Neoplasias Laríngeas/metabolismo , Fator Estimulador de Colônias de Macrófagos/metabolismo , Macrófagos/metabolismo , Monócitos/patologia , Linhagem Celular , Neoplasias Colorretais/patologia , Citocinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Humanos , Interleucina-12/metabolismo , Neoplasias Laríngeas/patologia , Fenótipo , Células Tumorais Cultivadas
17.
Roum Arch Microbiol Immunol ; 70(1): 28-36, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21717809

RESUMO

CANTASTIM is a second generation bacterial immunomodulator. The aim of this study was to examine the mechanism by which bacterial immunomodulator CANTASTIM induces production of inflammatory cytokines in monocytes/macrophages. Proinflammatory cytokines were induced in PMA-differentiated THP-1 cells by stimulation with TLR agonists and CANTASTIM in the presence or absence of anti-TLR blocking antibodies or isotype matched control antibodies. Also, RNA interference was used to knockdown TLR2 or TLR4 expression in PMA-differentiated THP-1 cells before stimulation. As expected, induction of TNF-alpha and IL-6 by TLR4 agonist LPS was inhibited in a significant manner by anti-TLR4 but not by anti-TLR2 antibody. Unexpectedly, treatment with anti-LR2 blocking antibody inhibited only IL-6 production induced by Pam3CSK4 while the level of TNF-alpha was unchanged. When cells were stimulated by TLR2 agonist heat-killed Listeria monocytogenes the release of TNF-alpha was significantly attenuated by anti-TLR2 antibodies. Silencing of TLR2 led to a statistically significant inhibition of TNF-alpha secretion induced by TLR2 agonist while siRNA silencing of TLR4 did not affect the response to TLR2 agonist. Cells exposed to CANTASTIM produced significant levels of pro-inflammatory cytokines but the levels were lower than LPS-stimulated cells. Production of both cytokines was inhibited by treatment with anti-TLR2 blocking antibody and not by anti-TLR4 antibody. Silencing of TLR2 led to a statistically significant inhibition of TNF-a secretion induced by CANTASTIM while silencing of TLR4 had no effect on the response to CANTASTIM. These results support the hypothesis that CANTASTIM may exert its immunomodulatory and adjuvant activities through interaction of its bacterial components with TLR2.


Assuntos
Ativação de Macrófagos/efeitos dos fármacos , Fosfolipídeos/farmacologia , Receptor 2 Toll-Like/fisiologia , Linhagem Celular , Humanos , Interleucina-6/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , Receptor 4 Toll-Like/fisiologia , Fator de Necrose Tumoral alfa/metabolismo
18.
J Otolaryngol Head Neck Surg ; 40(2): 143-50, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21453650

RESUMO

OBJECTIVE: Altered immune, inflammatory, and angiogenesis responses have been noticed in head and neck cancer, and many of these responses have been associated with a poor clinical outcome. The objective of this study was to evaluate several immune mediators in the sera of patients with squamous cell carcinoma (SCC) of the larynx undergoing curative surgery in connection with clinicopathologic factors. METHODS: Multiplex analysis of cytokines (interleukin [IL]-6, IL-8, IL-10, tumour necrosis factor α [TNF-α], interferon-γ [IFN-γ]), chemokines (monocyte chemoattractant protein 1 [MCP-1], macrophage inflammatory protein 1α [MIP-1α], and epithelial neutrophil-activating protein 78 [ENA-78]), and growth factors (vascular endothelial growth factor and basic fibroblast growth factor) in the serum of patients with laryngeal cancer and healthy controls was performed using xMap technology. RESULTS: Patients with SCC presented an altered cytokine profile compared to healthy controls, both preoperatively (higher levels of IL-8 and IL-10) and postoperatively (higher values for IL-6, IL-8, IL-10, and TNF-α). Heavy smoking was associated with significantly lower levels of ENA-78 and higher levels of IL-8. CONCLUSION: Differences noticed in patients' immune mediator profiles seem to be attributable to both disease and treatment. Further longitudinal studies are necessary to elucidate the involvement of immune mediators in disease progression and clinical evolution.


Assuntos
Carcinoma de Células Escamosas/sangue , Citocinas/sangue , Neoplasias Laríngeas/sangue , Adulto , Idoso , Carcinoma de Células Escamosas/imunologia , Carcinoma de Células Escamosas/cirurgia , Quimiocina CXCL5/análise , Feminino , Humanos , Interleucinas/sangue , Neoplasias Laríngeas/imunologia , Neoplasias Laríngeas/cirurgia , Masculino , Pessoa de Meia-Idade , Fumar , Fator de Necrose Tumoral alfa/sangue
19.
J Med Life ; 3(4): 416-20, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21254741

RESUMO

Adipose tissue displays characteristics of an endocrine organ releasing a number of adipocyte-specific factors known as adipocytokines. It has been recently suggested that adipocytokines may play a role in pathogenesis and progression of certain cancers, in particular in colorectal cancer. The aim of this study was to investigate the association between several blood adipocytokine levels and clinicopathological characteristics of colon cancer patients undergoing surgery. The study group comprised of 29 patients who underwent surgical resection for colon cancer at Emergency University Hospital Bucharest and 27 healthy volunteers. The serum levels of adipocytokines were measured using multianalyte xMap profiling technology (Luminex). Resistin levels were significantly higher in colon cancer patients while leptin serum levels were significantly lower as compared to controls. Leptin levels decreased gradually with tumor stage and aggressiveness. Taken together, these results of this study suggest that adipokines, in particular resistin and leptin may be involved in development and progression of colon cancer.


Assuntos
Colo/patologia , Neoplasias do Colo/sangue , Neoplasias do Colo/patologia , Leptina/sangue , Resistina/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Diferenciação Celular , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/sangue
20.
Mycopathologia ; 167(6): 333-40, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19194784

RESUMO

Neonates are highly sensitive to infections because they are biased to develop Th2 immune responses. When exposed to certain agents, such as DNA vaccines or CpG DNA motifs, neonates are capable to mount adult-like Th1 protective responses. This study investigates the capacity of Candida albicans (C. albicans) dsDNA to induce host resistance in newborn mice against gastrointestinal C. albicans infection. The protective properties of dsDNA are related to an increased number of spleen CD4+ T cells secreting IFN-gamma. In infected DNA-treated mice, an enhanced production of IFN-gamma by Peyer's patch cells was observed together with reduced colonization and histopathological changes in the stomach. Our results indicated that C. albicans dsDNA administration in neonates elicited the protective immune response against gastrointestinal Candida infection.


Assuntos
Candida albicans/fisiologia , Candidíase/microbiologia , DNA Fúngico/farmacologia , DNA/farmacologia , Gastroenteropatias/microbiologia , Macrófagos/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Candida albicans/genética , Candida albicans/imunologia , DNA/imunologia , DNA Fúngico/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Gastroenteropatias/imunologia , Interferon gama/metabolismo , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C
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