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1.
Plants (Basel) ; 12(12)2023 Jun 12.
Article in English | MEDLINE | ID: mdl-37375920

ABSTRACT

The demand for soybeans in Europe motivates breeders, researchers, and growers to find suitable cultivars to adapt and extend the soybean crop to improper climate areas. Weed control is a crucial aspect of crop technology in organic agriculture, but particularly for soybean crops. In laboratory conditions, the cumulative stress index for seedlings was determined to identify the susceptible cultivars. A field experiment with 14 soybean accessions and 2 sowing dates was conducted under organic farming conditions over the course of three years, from 2020 to 2022. Plant population density was found to be significantly (p < 0.01 and p < 0.1) negatively correlated to the degree of resistance to low temperature as well as infestation degree with weeds (for p < 0.05 and p < 0.1), with the exception of early sowing in 2021. Yield was significantly (p < 0.05, p < 0.01, p < 0.1) correlated with plant population density, with the exception of optimal sowing in 2022. Early sowing variants emerged with vigor in the first two years, breeding lines and registered varieties showed low input, and organic agriculture systems showed low yields in the drought years of 2020 and 2022. Although early sowing even in the first two years proved to be a practice that increased the cultivars' performance, in 2022, due to the long period of chilling stress in the field, this option had negative effects on yield due to the high weed frequency. Therefore, the early sowing strategy for the soybean crop in this particular case of non-irrigated conditions in a temperate continental area proved to be a risky practice.

2.
Sci Rep ; 13(1): 8499, 2023 05 25.
Article in English | MEDLINE | ID: mdl-37231015

ABSTRACT

The Gumelnița site belongs to the Kodjadermen-Gumelnița-Karanovo VI (KGK VI) communities (c. 4700-3900 cal BC) and comprises the tell-type settlement and its corresponding cemetery. This paper reconstructs the diet and lifeways of the Chalcolithic people in the northeastern Balkans using archaeological remains found at the Gumelnița site (Romania). A multi-bioarchaeological investigation (archaeobotany, zooarchaeology, anthropology) was conducted on vegetal, animal, and human remains, alongside radiocarbon dating and stable isotope analyses (δ13C, δ15N) of humans (n = 33), mammals (n = 38), reptiles (n = 3), fishes (n = 8), freshwater mussels shells (n = 18), and plants (n = 24). According to the results of δ13C and δ15N values and FRUITS, the inhabitants of Gumelnița had a diet based on crops and using natural resources, such as fish, freshwater molluscs and game. Although domestic fauna was occasionally exploited for meat, it had a role in providing secondary products. Crops were heavily manured, and chaff and other crop waste may have been necessary fodder for cattle and sheep. Dogs and pigs fed on human waste, although the diet of the latter is more similar to that of wild boars. Foxes had a diet close to dogs, which may indicate synanthropic behaviour. Radiocarbon dates were calibrated with the percentage of freshwater resources obtained by FRUITS. As a result, the corrected dates for the freshwater reservoir effect (FRE) have a delay of an average of 147 years. According to our data, this agrarian community developed a subsistence strategy under the pressure of some climatic changes that started after 4300 cal BC, corresponding to KGK VI rapid collapse/decline episode tracked recently (that begins around 4350 cal BC). This matching of our data in the two models (climatic and chrono-demographic) allowed us to capture the economic strategies that led to the resilience of those people more than other contemporary KGK VI communities.


Subject(s)
Bone and Bones , Isotopes , Humans , Animals , Cattle , Swine , Sheep , Dogs , History, Ancient , Romania , Nitrogen Isotopes/analysis , Bone and Bones/chemistry , Isotopes/analysis , Diet , Cemeteries , Fishes , Carbon Isotopes/analysis , Mammals
3.
Plant Biotechnol J ; 21(6): 1176-1190, 2023 06.
Article in English | MEDLINE | ID: mdl-36779605

ABSTRACT

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.


Subject(s)
COVID-19 , Hepatitis B virus , Humans , Animals , Mice , Hepatitis B virus/genetics , Glycosylation , Nicotiana/genetics , CRISPR-Cas Systems/genetics , COVID-19/genetics , SARS-CoV-2 , Hepatitis B Vaccines/genetics , Antibodies, Neutralizing , Hepatitis B Surface Antigens/genetics
4.
Front Immunol ; 13: 941243, 2022.
Article in English | MEDLINE | ID: mdl-35935966

ABSTRACT

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.


Subject(s)
Hepatitis B Surface Antigens , Hepatitis B virus , Animals , Antibodies, Blocking , Antibodies, Neutralizing , Hepatitis B Vaccines , Immunity, Humoral , Mammals , Mice , Mice, Inbred BALB C , Vaccines, Synthetic
5.
Data Brief ; 42: 108114, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35510265

ABSTRACT

Stable isotopic ratios of carbon and nitrogen performed on collagen and tooth enamel offer invaluable insight into the diet of ancient populations. In the northern Balkans, most of these isotopic data have been collected as auxiliary information of radiocarbon dates, to correct a potential marine reservoir effect. In order to facilitate the access of the academic community to these data, we present a set of isotopic carbon and nitrogen ratios of human collagen samples for 188 individuals from 12 previously published sites together with hitherto unreleased data for 24 individuals from 4 sites from the Neolithic and Eneolithic period in Bulgaria and Romania. This collection also includes previously published carbon isotopic ratio measurements on tooth enamel of 34 individuals.

6.
Methods Mol Biol ; 2183: 83-94, 2021.
Article in English | MEDLINE | ID: mdl-32959242

ABSTRACT

The small (S) envelope protein of the Hepatitis B Virus (HBV), HBV-S, has the unique ability to self-assemble into highly immunogenic subviral particles (SVPs), in the absence of other viral factors, in eukaryotic cells, including those of nonhepatic origin. This feature is currently exploited for generation of SVPs exposing heterologous epitopes on their surface that can be used as vaccine candidates to target various diseases. Here, we describe a simple and robust method for production of such chimeric HBV-S protein-based SVPs in transiently transfected HEK293T cells and purification from cell supernatants by ultracentrifugation on sucrose cushion and sucrose step gradients. The SVPs obtained by this methodology have been successfully used in immunogenicity studies in animal models.


Subject(s)
Batch Cell Culture Techniques , Hepatitis B Surface Antigens/biosynthesis , Recombinant Fusion Proteins , Animals , Cell Culture Techniques , Gene Expression , HEK293 Cells , Hepatitis B Surface Antigens/genetics , Hepatitis B Surface Antigens/immunology , Hepatitis B Surface Antigens/isolation & purification , Hepatitis B Vaccines/biosynthesis , Hepatitis B Vaccines/immunology , Humans , Transfection
7.
Cells ; 9(6)2020 06 04.
Article in English | MEDLINE | ID: mdl-32512942

ABSTRACT

Hepatitis B Virus (HBV) glycobiology has been an area of intensive research in the last decades and continues to be an attractive topic due to the multiple roles that N-glycosylation in particular plays in the virus life-cycle and its interaction with the host that are still being discovered. The three HBV envelope glycoproteins, small (S), medium (M) and large (L) share a very peculiar N-glycosylation pattern, which distinctly regulates their folding, degradation, assembly, intracellular trafficking and antigenic properties. In addition, recent findings indicate important roles of N-linked oligosaccharides in viral pathogenesis and evasion of the immune system surveillance. This review focuses on N-glycosylation's contribution to HBV infection and disease, with implications for development of improved vaccines and antiviral therapies.


Subject(s)
Hepatitis B virus/physiology , Polysaccharides/metabolism , Animals , Glycosylation , Hepatitis B Vaccines/immunology , Host-Pathogen Interactions , Humans , Proteolysis
8.
Vaccine ; 36(38): 5789-5795, 2018 09 11.
Article in English | MEDLINE | ID: mdl-30082163

ABSTRACT

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.


Subject(s)
Antibodies, Neutralizing/blood , Antibodies, Viral/blood , Hepatitis B Surface Antigens/immunology , Hepatitis B Vaccines/immunology , Hepatitis B virus/immunology , Hepatitis B/prevention & control , Protein Precursors/immunology , Administration, Oral , Animals , Cell Line, Tumor , Female , Hep G2 Cells , Hepatitis B Vaccines/administration & dosage , Humans , Lactuca/genetics , Lactuca/metabolism , Mice , Mice, Inbred BALB C , Recombinant Fusion Proteins/immunology , Vaccination , Viral Envelope Proteins/immunology
9.
Antiviral Res ; 144: 256-265, 2017 08.
Article in English | MEDLINE | ID: mdl-28666757

ABSTRACT

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.


Subject(s)
Hepatitis B Surface Antigens/immunology , Hepatitis B Vaccines/immunology , Vaccines, Virus-Like Particle/immunology , Animals , Cell Line , Hepatitis B Antibodies/blood , Hepatitis B Surface Antigens/genetics , Hepatitis B Vaccines/administration & dosage , Hepatitis B Vaccines/genetics , Hepatitis B Vaccines/isolation & purification , Humans , Interferon-gamma/metabolism , Leukocytes, Mononuclear/immunology , Mice, Inbred BALB C , Recombinant Proteins/genetics , Recombinant Proteins/immunology , Spleen/immunology , Nicotiana , Vaccines, Synthetic/administration & dosage , Vaccines, Synthetic/genetics , Vaccines, Synthetic/immunology , Vaccines, Synthetic/isolation & purification , Vaccines, Virus-Like Particle/administration & dosage , Vaccines, Virus-Like Particle/genetics , Vaccines, Virus-Like Particle/isolation & purification
10.
Curr Biol ; 27(12): 1801-1810.e10, 2017 Jun 19.
Article in English | MEDLINE | ID: mdl-28552360

ABSTRACT

The transition from hunting and gathering to farming involved profound cultural and technological changes. In Western and Central Europe, these changes occurred rapidly and synchronously after the arrival of early farmers of Anatolian origin [1-3], who largely replaced the local Mesolithic hunter-gatherers [1, 4-6]. Further east, in the Baltic region, the transition was gradual, with little or no genetic input from incoming farmers [7]. Here we use ancient DNA to investigate the relationship between hunter-gatherers and farmers in the Lower Danube basin, a geographically intermediate area that is characterized by a rapid Neolithic transition but also by the presence of archaeological evidence that points to cultural exchange, and thus possible admixture, between hunter-gatherers and farmers. We recovered four human paleogenomes (1.1× to 4.1× coverage) from Romania spanning a time transect between 8.8 thousand years ago (kya) and 5.4 kya and supplemented them with two Mesolithic genomes (1.7× and 5.3×) from Spain to provide further context on the genetic background of Mesolithic Europe. Our results show major Western hunter-gatherer (WHG) ancestry in a Romanian Eneolithic sample with a minor, but sizeable, contribution from Anatolian farmers, suggesting multiple admixture events between hunter-gatherers and farmers. Dietary stable-isotope analysis of this sample suggests a mixed terrestrial/aquatic diet. Our results provide support for complex interactions among hunter-gatherers and farmers in the Danube basin, demonstrating that in some regions, demic and cultural diffusion were not mutually exclusive, but merely the ends of a continuum for the process of Neolithization.


Subject(s)
Archaeology , DNA, Ancient/analysis , Diet , Genome, Human , Human Migration , Cultural Evolution , Farmers , Humans , Life Style , Romania
11.
Plant Biotechnol J ; 15(12): 1611-1621, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28419665

ABSTRACT

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.


Subject(s)
Lactuca/genetics , Viral Envelope Proteins/immunology , Viral Hepatitis Vaccines/administration & dosage , Viral Hepatitis Vaccines/immunology , Administration, Oral , Animals , Female , HEK293 Cells , Humans , Immunity, Humoral , Mice, Inbred BALB C , Plants, Genetically Modified , Protein Engineering/methods , Protein Multimerization , Recombinant Proteins/genetics , Recombinant Proteins/immunology , Recombinant Proteins/isolation & purification , Viral Envelope Proteins/genetics , Viral Hepatitis Vaccines/genetics
12.
Cell Microbiol ; 19(2)2017 02.
Article in English | MEDLINE | ID: mdl-27490136

ABSTRACT

Cells replicating the human hepatitis B virus (HBV) express high levels of degradation-enhancing α-mannosidase-like proteins (EDEMs), a family of proteins involved in the endoplasmic reticulum associated degradation, one of the pathways activated during the unfolded protein response. Owing to their α-1,2 mannosidase activity, the EDEM1-3 proteins are able to process the N-linked glycans of misfolded or incompletely folded proteins, providing the recognition signal for their subsequent degradation. The HBV small (S), medium (M), and large (L) surface proteins bear an N-linked glycosylation site in the common S domain that is partially occupied in all proteins. The M protein contains an additional site in its preS2 domain, which is always functional. Here, we report that these oligosaccharides are processed by EDEMs, more efficiently by EDEM3, which induces degradation of L and S proteins, accompanied by a reduction of subviral particles production. In striking contrast, M not only is spared from degradation but its trafficking is also accelerated leading to an improved secretion. This unusual behavior of the M protein requires strictly the mannose trimming of the preS2 N-linked glycan. Furthermore, we show that HBV secretion is significantly inhibited under strong endoplasmic reticulum stress conditions when M expression is prevented by mutagenesis of the viral genome. These observations unfold unique properties of the M protein in the HBV life cycle during unfolded protein response and point to alternative mechanisms employed by EDEMs to alleviate this stress in case of necessity by promoting glycoprotein trafficking rather than degradation.


Subject(s)
Endoplasmic Reticulum/metabolism , Hepatitis B virus/physiology , Host-Pathogen Interactions , Viral Envelope Proteins/metabolism , alpha-Mannosidase/metabolism , Cell Line , Endoplasmic Reticulum Stress , Humans , Protein Processing, Post-Translational , Protein Transport
13.
PLoS One ; 10(6): e0128810, 2015.
Article in English | MEDLINE | ID: mdl-26053041

ABSTRACT

The importance of the process of Neolithization for the genetic make-up of European populations has been hotly debated, with shifting hypotheses from a demic diffusion (DD) to a cultural diffusion (CD) model. In this regard, ancient DNA data from the Balkan Peninsula, which is an important source of information to assess the process of Neolithization in Europe, is however missing. In the present study we show genetic information on ancient populations of the South-East of Europe. We assessed mtDNA from ten sites from the current territory of Romania, spanning a time-period from the Early Neolithic to the Late Bronze Age. mtDNA data from Early Neolithic farmers of the Starcevo Cris culture in Romania (Cârcea, Gura Baciului and Negrilesti sites), confirm their genetic relationship with those of the LBK culture (Linienbandkeramik Kultur) in Central Europe, and they show little genetic continuity with modern European populations. On the other hand, populations of the Middle-Late Neolithic (Boian, Zau and Gumelnita cultures), supposedly a second wave of Neolithic migration from Anatolia, had a much stronger effect on the genetic heritage of the European populations. In contrast, we find a smaller contribution of Late Bronze Age migrations to the genetic composition of Europeans. Based on these findings, we propose that permeation of mtDNA lineages from a second wave of Middle-Late Neolithic migration from North-West Anatolia into the Balkan Peninsula and Central Europe represent an important contribution to the genetic shift between Early and Late Neolithic populations in Europe, and consequently to the genetic make-up of modern European populations.


Subject(s)
DNA, Mitochondrial/genetics , Genetic Variation , Genetics, Population , Geography , Haplotypes/genetics , Humans , Multivariate Analysis , Principal Component Analysis , Romania , Time Factors
15.
Philos Trans R Soc Lond B Biol Sci ; 370(1660): 20130616, 2015 Jan 19.
Article in English | MEDLINE | ID: mdl-25487340

ABSTRACT

Current evidence suggests that pigs were first domesticated in Eastern Anatolia during the ninth millennium cal BC before dispersing into Europe with Early Neolithic farmers from the beginning of the seventh millennium. Recent ancient DNA (aDNA) research also indicates the incorporation of European wild boar into domestic stock during the Neolithization process. In order to establish the timing of the arrival of domestic pigs into Europe, and to test hypotheses regarding the role European wild boar played in the domestication process, we combined a geometric morphometric analysis (allowing us to combine tooth size and shape) of 449 Romanian ancient teeth with aDNA analysis. Our results firstly substantiate claims that the first domestic pigs in Romania possessed the same mtDNA signatures found in Neolithic pigs in west and central Anatolia. Second, we identified a significant proportion of individuals with large molars whose tooth shape matched that of archaeological (likely) domestic pigs. These large 'domestic shape' specimens were present from the outset of the Romanian Neolithic (6100-5500 cal BC) through to later prehistory, suggesting a long history of admixture between introduced domestic pigs and local wild boar. Finally, we confirmed a turnover in mitochondrial lineages found in domestic pigs, possibly coincident with human migration into Anatolia and the Levant that occurred in later prehistory.


Subject(s)
Biological Evolution , DNA/genetics , Fossils , Hybridization, Genetic , Paleontology/methods , Sus scrofa/anatomy & histology , Sus scrofa/genetics , Animals , Body Weights and Measures , DNA/history , History, Ancient , Humans , Romania , Tooth/anatomy & histology , Tooth/chemistry
16.
Front Microbiol ; 5: 433, 2014.
Article in English | MEDLINE | ID: mdl-25191311

ABSTRACT

During productive viral infection the host cell is confronted with synthesis of a vast amount of viral proteins which must be folded, quality controlled, assembled and secreted, perturbing the normal function of the endoplasmic reticulum (ER). To counteract the ER stress, cells activate specific signaling pathways, designated as the unfolded proteins response (UPR), which essentially increase their folding capacity, arrest protein translation, and degrade the excess of misfolded proteins. This cellular defense mechanism may, in turn, affect significantly the virus life-cycle. This review highlights the current understanding of the mechanisms of the ER stress activation by Human Hepatitis B virus (HBV), a deadly pathogen affecting more than 350 million people worldwide. Further discussion addresses the latest discoveries regarding the adaptive strategies developed by HBV to manipulate the UPR for its own benefits, the controversies in the field and future perspectives.

17.
Adv Exp Med Biol ; 806: 453-81, 2014.
Article in English | MEDLINE | ID: mdl-24952197

ABSTRACT

Infection with Hepatitis B virus (HBV) is the most common cause of liver disease in the world. Infection becomes chronic in up to 10 % of adults, with severe consequences on liver function, including inflammation, fibrosis, cirrhosis, and eventually hepatocellular carcinoma (HCC). HCC is a fast progressing disease causing the death of approximately one million patients annually; current treatment has very limited success, mainly due to late-stage diagnosis and poor screening methodologies. Therefore, unraveling the complex HBV-host cell interactions during progression of the disease is of crucial importance, not only to understand the mechanisms underlying carcinogenesis, but importantly, for the development of new biomarkers for prognostic and early diagnosis. This is an area of research strongly influenced by proteomic studies, which have benefited in the last decade from major technical improvements in accuracy of quantification and sensitivity, large-scale analysis of low-abundant proteins, such as those from clinical samples being now possible and widely applied. This work is a critical review of the impact of the proteomic studies on our current understanding of HBV-associated pathogenesis, diagnostics, and treatment.


Subject(s)
Carcinoma, Hepatocellular/metabolism , Hepatitis B virus/physiology , Hepatitis B/metabolism , Liver Neoplasms/metabolism , Neoplasm Proteins/metabolism , Proteomics/methods , Viral Proteins/metabolism , Virus Replication/physiology , Adult , Animals , Carcinoma, Hepatocellular/diagnosis , Carcinoma, Hepatocellular/therapy , Hepatitis B/diagnosis , Hepatitis B/therapy , Humans , Liver Neoplasms/diagnosis , Liver Neoplasms/therapy
18.
Hepatology ; 59(2): 375-84, 2014 Feb.
Article in English | MEDLINE | ID: mdl-23775568

ABSTRACT

UNLABELLED: Hepatitis C virus (HCV) is a major cause of global morbidity, causing chronic liver injury that can progress to cirrhosis and hepatocellular carcinoma. The liver is a large and complex organ containing multiple cell types, including hepatocytes, sinusoidal endothelial cells (LSEC), Kupffer cells, and biliary epithelial cells. Hepatocytes are the major reservoir supporting HCV replication; however, the role of nonparenchymal cells in the viral lifecycle remains largely unexplored. LSEC secrete factors that promote HCV infection and transcript analysis identified bone morphogenetic protein 4 (BMP4) as a candidate endothelial-expressed proviral molecule. Recombinant BMP4 increased HCV replication and neutralization of BMP4 abrogated the proviral activity of LSEC-conditioned media. Importantly, BMP4 expression was negatively regulated by vascular endothelial growth factor A (VEGF-A) by way of a VEGF receptor-2 (VEGFR-2) primed activation of p38 MAPK. Consistent with our in vitro observations, we demonstrate that in normal liver VEGFR-2 is activated and BMP4 expression is suppressed. In contrast, in chronic liver disease including HCV infection where there is marked endothelial cell proliferation, we observed reduced endothelial cell VEGFR-2 activation and a concomitant increase in BMP4 expression. CONCLUSION: These studies identify a role for LSEC and BMP4 in HCV infection and highlight BMP4 as a new therapeutic target for treating individuals with liver disease.


Subject(s)
Endothelial Cells/metabolism , Hepacivirus/physiology , Liver/metabolism , Paracrine Communication/physiology , Virus Replication/physiology , Bone Morphogenetic Protein 4/metabolism , Cell Proliferation , Cells, Cultured , Endothelial Cells/pathology , Hepatocytes/pathology , Hepatocytes/virology , Humans , In Vitro Techniques , Liver/pathology , Vascular Endothelial Growth Factor A/metabolism , Vascular Endothelial Growth Factor Receptor-2/metabolism , p38 Mitogen-Activated Protein Kinases/metabolism
19.
PLoS One ; 8(8): e71859, 2013.
Article in English | MEDLINE | ID: mdl-23977166

ABSTRACT

Hepatitis B virus (HBV) is a human pathogen causing severe liver disease and eventually death. Despite important progress in deciphering HBV internalization, the early virus-cell interactions leading to infection are not known. HepaRG is a human bipotent liver cell line bearing the unique ability to differentiate towards a mixture of hepatocyte- and biliary-like cells. In addition to expressing metabolic functions normally found in liver, differentiated HepaRG cells support HBV infection in vitro, thus resembling cultured primary hepatocytes more than other hepatoma cells. Therefore, extensive characterization of the plasma membrane proteome from HepaRG cells would allow the identification of new cellular factors potentially involved in infection. Here we analyzed the plasma membranes of non-differentiated and differentiated HepaRG cells using nanoliquid chromatography-tandem mass spectrometry to identify the differences between the proteomes and the changes that lead to differentiation of these cells. We followed up on differentially-regulated proteins in hepatocytes- and biliary-like cells, focusing on Cathepsins D and K, Cyclophilin A, Annexin 1/A1, PDI and PDI A4/ERp72. Major differences between the two proteomes were found, including differentially regulated proteins, protein-protein interactions and intracellular localizations following differentiation. The results advance our current understanding of HepaRG differentiation and the unique properties of these cells.


Subject(s)
Cell Differentiation , Cell Membrane/metabolism , Hepatocytes/metabolism , Membrane Proteins/metabolism , Proteome/metabolism , Amino Acid Sequence , Cell Line, Tumor , Humans , Membrane Proteins/chemistry , Membrane Proteins/isolation & purification , Molecular Sequence Data , Peptide Fragments/chemistry , Peptide Mapping , Protein Transport , Proteome/chemistry , Proteome/isolation & purification , Proteomics , Up-Regulation
20.
J Med Virol ; 85(5): 780-8, 2013 May.
Article in English | MEDLINE | ID: mdl-23508903

ABSTRACT

Lactoferrin (Lf) was shown to exhibit its antiviral activity at an early phase of viral infection and a mechanism whereby the protein interacts with host cell surface molecules has been suggested. In this study, human Lf (HLf) and seven HLf-derived synthetic peptides (HLP) corresponding to the N-terminal domain of the native protein (1-47 amino acids sequence) were assayed for their capacity to prevent hepatitis B virus (HBV) infection and replication using the HepaRG and HepG2.2.2.15 cell lines. Of the series tested, four peptides showed 40-75% inhibition of HBV infection in HepaRG cells, HLP1-23 , containing the GRRRR cationic cluster, being the most potent. Interestingly, this cluster is one of the two glycosaminoglycan binding sites of the native HLf involved in its antiviral activity; however, the mechanism of the HLP1-23 action was different from that of the full-length protein, the peptide inhibiting HBV infection when pre-incubated with the virus, while no effect was observed on the target cells. It is suggested that the cationic cluster is sufficient for the peptide to interact stably with negatively charged residues on the virion envelope, while the absence of the second glycosaminoglycan binding site prevents its efficient attachment to the cells. In conclusion, this peptide may constitute a non-toxic approach for potential clinical applications in inhibiting HBV entry by neutralizing the viral particles.


Subject(s)
Antiviral Agents/pharmacology , Hepatitis B virus/drug effects , Lactoferrin/pharmacology , Peptide Fragments/pharmacology , Cell Line , Hepatitis B virus/physiology , Hepatocytes/virology , Humans , Virus Internalization/drug effects , Virus Replication/drug effects
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