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Viruses, Volume 6, Issue 6 (June 2014), Pages 2242-2530

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Research

Jump to: Review, Other

Open AccessArticle Clustering of Giant Virus-DNA Based on Variations in Local Entropy
Viruses 2014, 6(6), 2259-2267; doi:10.3390/v6062259
Received: 5 February 2014 / Revised: 19 May 2014 / Accepted: 21 May 2014 / Published: 30 May 2014
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Abstract
We present a method for clustering genomic sequences based on variations in local entropy. We have analyzed the distributions of the block entropies of viruses and plant genomes. A distinct pattern for viruses and plant genomes is observed. These distributions, which describe the
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We present a method for clustering genomic sequences based on variations in local entropy. We have analyzed the distributions of the block entropies of viruses and plant genomes. A distinct pattern for viruses and plant genomes is observed. These distributions, which describe the local entropic variability of the genomes, are used for clustering the genomes based on the Jensen-Shannon (JS) distances. The analysis of the JS distances between all genomes that infect the chlorella algae shows the host specificity of the viruses. We illustrate the efficacy of this entropy-based clustering technique by the segregation of plant and virus genomes into separate bins. Full article
(This article belongs to the Special Issue Giant Viruses)
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Open AccessArticle Infection with Non-Lethal West Nile Virus Eg101 Strain Induces Immunity that Protects Mice against the Lethal West Nile Virus NY99 Strain
Viruses 2014, 6(6), 2328-2339; doi:10.3390/v6062328
Received: 13 April 2014 / Revised: 25 May 2014 / Accepted: 30 May 2014 / Published: 6 June 2014
Cited by 3 | PDF Full-text (2766 KB) | HTML Full-text | XML Full-text
Abstract
Herein we demonstrate that infection of mice with West Nile virus (WNV) Eg101 provides protective immunity against lethal challenge with WNV NY99. Our data demonstrated that WNV Eg101 is largely non-virulent in adult mice when compared to WNV NY99. By day 6 after
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Herein we demonstrate that infection of mice with West Nile virus (WNV) Eg101 provides protective immunity against lethal challenge with WNV NY99. Our data demonstrated that WNV Eg101 is largely non-virulent in adult mice when compared to WNV NY99. By day 6 after infection, WNV-specific IgM and IgG antibodies, and neutralizing antibodies were detected in the serum of all WNV Eg101 infected mice. Plaque reduction neutralization test data demonstrated that serum from WNV Eg101 infected mice neutralized WNV Eg101 and WNV NY99 strains with similar efficiency. Three weeks after infection, WNV Eg101 immunized mice were challenged subcutaneously or intracranially with lethal dose of WNV NY99 and observed for additional three weeks. All the challenged mice were protected against disease and no morbidity and mortality was observed in any mice. In conclusion, our data for the first time demonstrate that infection of mice with WNV Eg101 induced high titers of WNV specific IgM and IgG antibodies, and cross-reactive neutralizing antibodies, and the resulting immunity protected all immunized animals from both subcutaneous and intracranial challenge with WNV NY99. These observations suggest that WNV Eg101 may be a suitable strain for the development of a vaccine in humans against virulent strains of WNV. Full article
(This article belongs to the Special Issue Virus-based Vaccines)
Open AccessArticle Engineered RNase P Ribozymes Effectively Inhibit Human Cytomegalovirus Gene Expression and Replication
Viruses 2014, 6(6), 2376-2391; doi:10.3390/v6062376
Received: 8 April 2014 / Revised: 19 May 2014 / Accepted: 23 May 2014 / Published: 13 June 2014
Cited by 5 | PDF Full-text (791 KB) | HTML Full-text | XML Full-text
Abstract
RNase P ribozyme can be engineered to be a sequence-specific gene-targeting agent with promising application in both basic research and clinical settings. By using an in vitro selection system, we have previously generated RNase P ribozyme variants that have better catalytic activity in
[...] Read more.
RNase P ribozyme can be engineered to be a sequence-specific gene-targeting agent with promising application in both basic research and clinical settings. By using an in vitro selection system, we have previously generated RNase P ribozyme variants that have better catalytic activity in cleaving an mRNA sequence than the wild type ribozyme. In this study, one of the variants was used to target the mRNA encoding human cytomegalovirus (HCMV) essential transcription factor immediate-early protein 2 (IE2). The variant was able to cleave IE2 mRNA in vitro 50-fold better than the wild type ribozyme. A reduction of about 98% in IE2 expression and a reduction of 3500-fold in viral production was observed in HCMV-infected cells expressing the variant compared to a 75% reduction in IE2 expression and a 100-fold reduction in viral production in cells expressing the ribozyme derived from the wild type sequence. These results suggest that ribozyme variants that are selected to be highly active in vitro are also more effective in inhibiting the expression of their targets in cultured cells. Our study demonstrates that RNase P ribozyme variants are efficient in reducing HCMV gene expression and growth and are potentially useful for anti-viral therapeutic application. Full article
(This article belongs to the Special Issue Recent CMV Research) Print Edition available
Open AccessArticle Efficient Strategy to Generate a Vectored Duck Enteritis Virus Delivering Envelope of Duck Tembusu Virus
Viruses 2014, 6(6), 2428-2443; doi:10.3390/v6062428
Received: 10 March 2014 / Revised: 18 May 2014 / Accepted: 21 May 2014 / Published: 20 June 2014
Cited by 3 | PDF Full-text (1173 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Duck Tembusu virus (DTMUV) is a recently emerging pathogenic flavivirus that has resulted in a huge economic loss in the duck industry. However, no vaccine is currently available to control this pathogen. Consequently, a practical strategy to construct a vaccine against this pathogen
[...] Read more.
Duck Tembusu virus (DTMUV) is a recently emerging pathogenic flavivirus that has resulted in a huge economic loss in the duck industry. However, no vaccine is currently available to control this pathogen. Consequently, a practical strategy to construct a vaccine against this pathogen should be determined. In this study, duck enteritis virus (DEV) was examined as a candidate vaccine vector to deliver the envelope (E) of DTMUV. A modified mini-F vector was inserted into the SORF3 and US2 gene junctions of the attenuated DEV vaccine strain C-KCE genome to generate an infectious bacterial artificial chromosome (BAC) of C-KCE (vBAC-C-KCE). The envelope (E) gene of DTMUV was inserted into the C-KCE genome through the mating-assisted genetically integrated cloning (MAGIC) strategy, resulting in the recombinant vector, pBAC-C-KCE-E. A bivalent vaccine C-KCE-E was generated by eliminating the BAC backbone. Immunofluorescence and western blot analysis results indicated that the E proteins were vigorously expressed in C-KCE-E-infected chicken embryo fibroblasts (CEFs). Duck experiments demonstrated that the insertion of the E gene did not alter the protective efficacy of C-KCE. Moreover, C-KCE-E-immunized ducks induced neutralization antibodies against DTMUV. These results demonstrated, for the first time, that recombinant C-KCE-E can serve as a potential bivalent vaccine against DEV and DTMUV. Full article
(This article belongs to the Special Issue Virus-based Vaccines)
Open AccessArticle Molecular Characterization of Watermelon Chlorotic Stunt Virus (WmCSV) from Palestine
Viruses 2014, 6(6), 2444-2462; doi:10.3390/v6062444
Received: 6 January 2014 / Revised: 10 June 2014 / Accepted: 13 June 2014 / Published: 20 June 2014
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Abstract
The incidence of watermelon chlorotic stunt disease and molecular characterization of the Palestinian isolate of Watermelon chlorotic stunt virus (WmCSV-[PAL]) are described in this study. Symptomatic leaf samples obtained from watermelon Citrullus lanatus (Thunb.), and cucumber (Cucumis sativus L.) plants were tested
[...] Read more.
The incidence of watermelon chlorotic stunt disease and molecular characterization of the Palestinian isolate of Watermelon chlorotic stunt virus (WmCSV-[PAL]) are described in this study. Symptomatic leaf samples obtained from watermelon Citrullus lanatus (Thunb.), and cucumber (Cucumis sativus L.) plants were tested for WmCSV-[PAL] infection by polymerase chain reaction (PCR) and Rolling Circle Amplification (RCA). Disease incidence ranged between 25%–98% in watermelon fields in the studied area, 77% of leaf samples collected from Jenin were found to be mixed infected with WmCSV-[PAL] and SLCV. The full-length DNA-A and DNA-B genomes of WmCSV-[PAL] were amplified and sequenced, and the sequences were deposited in the GenBank. Sequence analysis of virus genomes showed that DNA-A and DNA-B had 97.6%–99.42% and 93.16%–98.26% nucleotide identity with other virus isolates in the region, respectively. Sequence analysis also revealed that the Palestinian isolate of WmCSV shared the highest nucleotide identity with an isolate from Israel suggesting that the virus was introduced to Palestine from Israel. Full article
(This article belongs to the Special Issue Plant Viruses)
Figures

Open AccessArticle A Novel Strain of Porcine Adenovirus Detected in Urinary Bladder Urothelial Cell Culture
Viruses 2014, 6(6), 2505-2518; doi:10.3390/v6062505
Received: 30 April 2014 / Revised: 9 June 2014 / Accepted: 17 June 2014 / Published: 23 June 2014
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Abstract
Contamination of cell cultures is the most common problem encountered in cell culture laboratories. Besides the secondary cell contaminations often occurring in the cell laboratories, the contaminations originating from donor animal or human tissue are equally as common, but usually harder to recognize
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Contamination of cell cultures is the most common problem encountered in cell culture laboratories. Besides the secondary cell contaminations often occurring in the cell laboratories, the contaminations originating from donor animal or human tissue are equally as common, but usually harder to recognize and as such require special attention. The present study describes the detection of porcine adenovirus (PAdV), strain PAdV-SVN1 in cultures of normal porcine urothelial (NPU) cells isolated from urinary bladders of domestic pigs. NPU cell cultures were evaluated by light microscopy (LM), polymerase chain reaction (PCR), and additionally assessed by transmission electron microscopy (TEM). Characteristic ultrastructure of virions revealed the infection with adenovirus. The adenoviral contamination was further identified by the sequence analysis, which showed the highest similarity to recently described PAdV strain PAdV-WI. Additionally, the cell ultrastructural analysis confirmed the life-cycle characteristic for adenoviruses. To closely mimic the in vivo situation, the majority of research on in vitro models uses cell cultures isolated from human or animal tissue and their subsequent passages. Since the donor tissue could be a potential source of contamination, the microbiological screening of the excised tissue and harvested cell cultures is highly recommended. Full article
(This article belongs to the Special Issue Electron Microscopy in Virus Diagnostics and Research)
Open AccessArticle Seroprevalence of Human Herpesvirus 8 and Hepatitis C Virus among Drug Users in Shanghai, China
Viruses 2014, 6(6), 2519-2530; doi:10.3390/v6062519
Received: 1 April 2014 / Revised: 2 June 2014 / Accepted: 6 June 2014 / Published: 23 June 2014
Cited by 2 | PDF Full-text (610 KB) | HTML Full-text | XML Full-text
Abstract
To elucidate and compare the seroprevalence of human herpesvirus 8 (HHV8) and hepatitis C virus (HCV) among Chinese drug users, a cross-sectional study of 441 participants, was conducted in Shanghai, China, from 2012 through 2013. Seventy-seven (17.5%) participants were found to be positive
[...] Read more.
To elucidate and compare the seroprevalence of human herpesvirus 8 (HHV8) and hepatitis C virus (HCV) among Chinese drug users, a cross-sectional study of 441 participants, was conducted in Shanghai, China, from 2012 through 2013. Seventy-seven (17.5%) participants were found to be positive for HHV8 antibodies, while 271 (61.5%) participants were positive for HCV. No significant association between HHV8 seropositivity and drug use characteristics, sexual behaviors, HCV, or syphilis was observed. In contrast, a statistically significant association between HCV seropositivity and injected drug history (OR, 2.18, 95% CI 1.41–3.37) was detected, whereas no statistically significant association between HCV seropositivity and syphilis infection (OR, 7.56, 95% CI 0.94–60.57) were observed. Pairwise comparisons showed no significant differences between latent and lytic antibodies regarding HCV and HHV8 serostatus. The study demonstrated a moderate but elevated prevalence of HHV8 infection among drug users. The discordance between HHV8 and HCV infections suggests that blood borne transmission of HHV8 might not be the predominant mode of transmission in this population, which is in contrast to HCV. Full article
(This article belongs to the Special Issue Kaposi's Sarcoma-Associated Herpesvirus) Print Edition available

Review

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Open AccessReview Controlling Cytomegalovirus: Helping the Immune System Take the Lead
Viruses 2014, 6(6), 2242-2258; doi:10.3390/v6062242
Received: 4 February 2014 / Revised: 9 May 2014 / Accepted: 13 May 2014 / Published: 27 May 2014
Cited by 13 | PDF Full-text (682 KB) | HTML Full-text | XML Full-text
Abstract
Cytomegalovirus, of the Herpesviridae family, has evolved alongside humans for thousands of years with an intricate balance of latency, immune evasion, and transmission. While upwards of 70% of humans have evidence of CMV infection, the majority of healthy people show little to no
[...] Read more.
Cytomegalovirus, of the Herpesviridae family, has evolved alongside humans for thousands of years with an intricate balance of latency, immune evasion, and transmission. While upwards of 70% of humans have evidence of CMV infection, the majority of healthy people show little to no clinical symptoms of primary infection and CMV disease is rarely observed during persistent infection in immunocompetent hosts. Despite the fact that the majority of infected individuals are asymptomatic, immunologically, CMV hijacks the immune system by infecting and remaining latent in antigen-presenting cells that occasionally reactivate subclinically and present antigen to T cells, eventually causing the inflation of CMV-specific T cells until they can compromise up to 10% of the entire T cell repertoire. Because of this impact on the immune system, as well as its importance in fields such as stem cell and organ transplant, the relationship between CMV and the immune response has been studied in depth. Here we provide a review of many of these studies and insights into how CMV-specific T cells are currently being used therapeutically. Full article
(This article belongs to the Special Issue Recent CMV Research) Print Edition available
Open AccessReview The Tumor-Associated Marker, PVRL4 (Nectin-4), Is the Epithelial Receptor for Morbilliviruses
Viruses 2014, 6(6), 2268-2286; doi:10.3390/v6062268
Received: 19 March 2014 / Revised: 14 May 2014 / Accepted: 15 May 2014 / Published: 2 June 2014
Cited by 9 | PDF Full-text (2921 KB) | HTML Full-text | XML Full-text
Abstract
PVRL4 (nectin-4) was recently identified as the epithelial receptor for members of the Morbillivirus genus, including measles virus, canine distemper virus and peste des petits ruminants virus. Here, we describe the role of PVRL4 in morbillivirus pathogenesis and its promising use in cancer
[...] Read more.
PVRL4 (nectin-4) was recently identified as the epithelial receptor for members of the Morbillivirus genus, including measles virus, canine distemper virus and peste des petits ruminants virus. Here, we describe the role of PVRL4 in morbillivirus pathogenesis and its promising use in cancer therapies. This discovery establishes a new paradigm for the spread of virus from lymphocytes to airway epithelial cells and its subsequent release into the environment. Measles virus vaccine strains have emerged as a promising oncolytic platform for cancer therapy in the last ten years. Given that PVRL4 is a well-known tumor-associated marker for several adenocarcinoma (lung, breast and ovary), the measles virus could potentially be used to specifically target, infect and destroy cancers expressing PVRL4. Full article
(This article belongs to the Special Issue Morbillivirus Infections)
Open AccessReview Peste Des Petits Ruminants Virus Infection of Small Ruminants: A Comprehensive Review
Viruses 2014, 6(6), 2287-2327; doi:10.3390/v6062287
Received: 13 March 2014 / Revised: 26 May 2014 / Accepted: 28 May 2014 / Published: 6 June 2014
Cited by 18 | PDF Full-text (1028 KB) | HTML Full-text | XML Full-text
Abstract
Peste des petits ruminants (PPR) is caused by a Morbillivirus that belongs to the family Paramyxoviridae. PPR is an acute, highly contagious and fatal disease primarily affecting goats and sheep, whereas cattle undergo sub-clinical infection. With morbidity and mortality rates that can be
[...] Read more.
Peste des petits ruminants (PPR) is caused by a Morbillivirus that belongs to the family Paramyxoviridae. PPR is an acute, highly contagious and fatal disease primarily affecting goats and sheep, whereas cattle undergo sub-clinical infection. With morbidity and mortality rates that can be as high as 90%, PPR is classified as an OIE (Office International des Epizooties)-listed disease. Considering the importance of sheep and goats in the livelihood of the poor and marginal farmers in Africa and South Asia, PPR is an important concern for food security and poverty alleviation. PPR virus (PPRV) and rinderpest virus (RPV) are closely related Morbilliviruses. Rinderpest has been globally eradicated by mass vaccination. Though a live attenuated vaccine is available against PPR for immunoprophylaxis, due to its instability in subtropical climate (thermo-sensitivity), unavailability of required doses and insufficient coverage (herd immunity), the disease control program has not been a great success. Further, emerging evidence of poor cross neutralization between vaccine strain and PPRV strains currently circulating in the field has raised concerns about the protective efficacy of the existing PPR vaccines. This review summarizes the recent advancement in PPRV replication, its pathogenesis, immune response to vaccine and disease control. Attempts have also been made to highlight the current trends in understanding the host susceptibility and resistance to PPR. Full article
(This article belongs to the Special Issue Morbillivirus Infections)
Open AccessReview Viral Oncolysis — Can Insights from Measles Be Transferred to Canine Distemper Virus?
Viruses 2014, 6(6), 2340-2375; doi:10.3390/v6062340
Received: 27 March 2014 / Revised: 3 June 2014 / Accepted: 4 June 2014 / Published: 11 June 2014
Cited by 4 | PDF Full-text (1372 KB) | HTML Full-text | XML Full-text
Abstract
Neoplastic diseases represent one of the most common causes of death among humans and animals. Currently available and applied therapeutic options often remain insufficient and unsatisfactory, therefore new and innovative strategies and approaches are highly needed. Periodically, oncolytic viruses have been in the
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Neoplastic diseases represent one of the most common causes of death among humans and animals. Currently available and applied therapeutic options often remain insufficient and unsatisfactory, therefore new and innovative strategies and approaches are highly needed. Periodically, oncolytic viruses have been in the center of interest since the first anecdotal description of their potential usefulness as an anti-tumor treatment concept. Though first reports referred to an incidental measles virus infection causing tumor regression in a patient suffering from lymphoma several decades ago, no final treatment concept has been developed since then. However, numerous viruses, such as herpes-, adeno- and paramyxoviruses, have been investigated, characterized, and modified with the aim to generate a new anti-cancer treatment option. Among the different viruses, measles virus still represents a highly interesting candidate for such an approach. Numerous different tumors of humans including malignant lymphoma, lung and colorectal adenocarcinoma, mesothelioma, and ovarian cancer, have been studied in vitro and in vivo as potential targets. Moreover, several concepts using different virus preparations are now in clinical trials in humans and may proceed to a new treatment option. Surprisingly, only few studies have investigated viral oncolysis in veterinary medicine. The close relationship between measles virus (MV) and canine distemper virus (CDV), both are morbilliviruses, and the fact that numerous tumors in dogs exhibit similarities to their human counterpart, indicates that both the virus and species dog represent a highly interesting translational model for future research in viral oncolysis. Several recent studies support such an assumption. It is therefore the aim of the present communication to outline the mechanisms of morbillivirus-mediated oncolysis and to stimulate further research in this potentially expanding field of viral oncolysis in a highly suitable translational animal model for the benefit of humans and dogs. Full article
(This article belongs to the Special Issue Morbillivirus Infections)
Open AccessReview Alphavirus-Based Vaccines
Viruses 2014, 6(6), 2392-2415; doi:10.3390/v6062392
Received: 2 April 2014 / Revised: 3 June 2014 / Accepted: 4 June 2014 / Published: 16 June 2014
Cited by 15 | PDF Full-text (742 KB) | HTML Full-text | XML Full-text
Abstract
Alphavirus vectors have demonstrated high levels of transient heterologous gene expression both in vitro and in vivo and, therefore, possess attractive features for vaccine development. The most commonly used delivery vectors are based on three single-stranded encapsulated alphaviruses, namely Semliki Forest virus, Sindbis
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Alphavirus vectors have demonstrated high levels of transient heterologous gene expression both in vitro and in vivo and, therefore, possess attractive features for vaccine development. The most commonly used delivery vectors are based on three single-stranded encapsulated alphaviruses, namely Semliki Forest virus, Sindbis virus and Venezuelan equine encephalitis virus. Alphavirus vectors have been applied as replication-deficient recombinant viral particles and, more recently, as replication-proficient particles. Moreover, in vitro transcribed RNA, as well as layered DNA vectors have been applied for immunization. A large number of highly immunogenic viral structural proteins expressed from alphavirus vectors have elicited strong neutralizing antibody responses in multispecies animal models. Furthermore, immunization studies have demonstrated robust protection against challenges with lethal doses of virus in rodents and primates. Similarly, vaccination with alphavirus vectors expressing tumor antigens resulted in prophylactic protection against challenges with tumor-inducing cancerous cells. As certain alphaviruses, such as Chikungunya virus, have been associated with epidemics in animals and humans, attention has also been paid to the development of vaccines against alphaviruses themselves. Recent progress in alphavirus vector development and vaccine technology has allowed conducting clinical trials in humans. Full article
(This article belongs to the Special Issue Virus-based Vaccines)
Open AccessReview Vaccination against δ-Retroviruses: The Bovine Leukemia Virus Paradigm
Viruses 2014, 6(6), 2416-2427; doi:10.3390/v6062416
Received: 30 April 2014 / Revised: 10 June 2014 / Accepted: 11 June 2014 / Published: 20 June 2014
Cited by 9 | PDF Full-text (658 KB) | HTML Full-text | XML Full-text
Abstract
Bovine leukemia virus (BLV) and human T-lymphotropic virus type 1 (HTLV-1) are closely related d-retroviruses that induce hematological diseases. HTLV-1 infects about 15 million people worldwide, mainly in subtropical areas. HTLV-1 induces a wide spectrum of diseases (e.g., HTLV-associated myelopathy/tropical spastic paraparesis) and
[...] Read more.
Bovine leukemia virus (BLV) and human T-lymphotropic virus type 1 (HTLV-1) are closely related d-retroviruses that induce hematological diseases. HTLV-1 infects about 15 million people worldwide, mainly in subtropical areas. HTLV-1 induces a wide spectrum of diseases (e.g., HTLV-associated myelopathy/tropical spastic paraparesis) and leukemia/lymphoma (adult T-cell leukemia). Bovine leukemia virus is a major pathogen of cattle, causing important economic losses due to a reduction in production, export limitations and lymphoma-associated death. In the absence of satisfactory treatment for these diseases and besides the prevention of transmission, the best option to reduce the prevalence of d-retroviruses is vaccination. Here, we provide an overview of the different vaccination strategies in the BLV model and outline key parameters required for vaccine efficacy. Full article
(This article belongs to the Special Issue Virus-based Vaccines)
Open AccessReview In the Shadow of Hemagglutinin: A Growing Interest in Influenza Viral Neuraminidase and Its Role as a Vaccine Antigen
Viruses 2014, 6(6), 2465-2494; doi:10.3390/v6062465
Received: 27 March 2014 / Revised: 6 June 2014 / Accepted: 13 June 2014 / Published: 23 June 2014
Cited by 21 | PDF Full-text (2285 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Despite the availability of vaccine prophylaxis and antiviral therapeutics, the influenza virus continues to have a significant, annual impact on the morbidity and mortality of human beings, highlighting the continued need for research in the field. Current vaccine strategies predominantly focus on raising
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Despite the availability of vaccine prophylaxis and antiviral therapeutics, the influenza virus continues to have a significant, annual impact on the morbidity and mortality of human beings, highlighting the continued need for research in the field. Current vaccine strategies predominantly focus on raising a humoral response against hemagglutinin (HA)—the more abundant, immunodominant glycoprotein on the surface of the influenza virus. In fact, anti-HA antibodies are often neutralizing, and are used routinely to assess vaccine immunogenicity. Neuraminidase (NA), the other major glycoprotein on the surface of the influenza virus, has historically served as the target for antiviral drug therapy and is much less studied in the context of humoral immunity. Yet, the quest to discern the exact importance of NA-based protection is decades old. Also, while antibodies against the NA glycoprotein fail to prevent infection of the influenza virus, anti-NA immunity has been shown to lessen the severity of disease, decrease viral lung titers in animal models, and reduce viral shedding. Growing evidence is intimating the possible gains of including the NA antigen in vaccine design, such as expanded strain coverage and increased overall immunogenicity of the vaccine. After giving a tour of general influenza virology, this review aims to discuss the influenza A virus neuraminidase while focusing on both the historical and present literature on the use of NA as a possible vaccine antigen. Full article
(This article belongs to the Special Issue Virus-based Vaccines)

Other

Jump to: Research, Review

Open AccessCorrection Correction: Buranda, T. et al. Equilibrium and Kinetics of Sin Nombre Hantavirus Binding at DAF/CD55 Functionalized Bead Surfaces. Viruses 2014, 6, 1091-1111
Viruses 2014, 6(6), 2463-2464; doi:10.3390/v6062463
Received: 13 June 2014 / Accepted: 14 June 2014 / Published: 20 June 2014
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Abstract
The procedure for blocking infection with H319 antibodies in polarized Vero E6 cells, grown in transwell inserts, was erroneously omitted on page 1104, Section 3.13. (entitled ‘Infectivity Assays’) of [1]. It is important to note that robust blocking with H319 anti-DAF anti-bodies,
[...] Read more.
The procedure for blocking infection with H319 antibodies in polarized Vero E6 cells, grown in transwell inserts, was erroneously omitted on page 1104, Section 3.13. (entitled ‘Infectivity Assays’) of [1]. It is important to note that robust blocking with H319 anti-DAF anti-bodies, as shown in Figure 5B, was measured in polarized cells, seeded on filter supports in transwell plates, as described below. [...] Full article
Open AccessBrief Report Genetic Diversity in HIV-1 Subtype C LTR from Brazil and Mozambique Generates New Transcription Factor-Binding Sites
Viruses 2014, 6(6), 2495-2504; doi:10.3390/v6062495
Received: 13 November 2013 / Revised: 12 January 2014 / Accepted: 24 January 2014 / Published: 23 June 2014
Cited by 1 | PDF Full-text (907 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
The HIV-1 subtype C has been substituting the subtype B population in southern Brazil. This phenomenon has been previously described in other countries, suggesting that subtype C may possess greater fitness than other subtypes. The HIV-1 long-terminal repeat (LTR) is an important regulatory
[...] Read more.
The HIV-1 subtype C has been substituting the subtype B population in southern Brazil. This phenomenon has been previously described in other countries, suggesting that subtype C may possess greater fitness than other subtypes. The HIV-1 long-terminal repeat (LTR) is an important regulatory region critical for the viral life cycle. Sequence insertions immediately upstream of the viral enhancer are known as the most frequent naturally occurring length polimorphisms (MFNLP). Previous reports demonstrated that the MFNLP could lead to the duplication of transcription factor binding sites (TFBS) enhancing the activity of the HIV-1 subtype C LTR. Here, we amplified and sequenced the LTR obtained from proviral DNA samples collected from patients infected with subtype C from the Southern Region of Brazil (naïve or treatment failure) and Mozambique (only naïve). We confirm the presence of different types of insertions in the LTR sequences of both the countries leading to the creation of additional TFBS. In the Brazilian clinical samples, the frequency of the sequence insertion was significantly higher in subjects experiencing treatment failure than in antiretroviral naïve patients. Full article
(This article belongs to the Special Issue HIV Drug Resistance)

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