•Comparison of enteric virome from malabsorption syndrome-affected and normal broilers.•Large diversity of the eukaryote viral community identified in broilers.•Novel and divergent circular ssDNA ...viruses detected in faecal samples from broilers.
Malabsorption syndrome (MAS) is an economically important disease of young, commercially reared broilers, characterized by growth retardation, defective feather development and diarrheic faeces. Several viruses have been tentatively associated to such syndrome. Here, in order to examine potential associations between enteric viruses and MAS, the faecal viromes of 70 stool samples collected from diseased (n = 35) and healthy (n = 35) chickens from seven flocks were characterized and compared. Following high-throughput sequencing, a total of 8,347,319 paired end reads, with an average of 231 nt, were generated. Through analysis of de novo assembled contigs, 144 contigs > 1000 nt were identified with hits to eukaryotic viral sequences, as determined by GenBank database. A number of known and unknown representatives of Adenoviridae, Anelloviridae, Astroviridae, Caliciviridae, Circoviridae, Parvoviridae, Picobirnaviridae, Picornaviridae and Reoviridae, as well as novel uncharacterized CRESS-DNA viruses, were identified. However, the distribution of sequence reads of viral genomes identified in diseased or healthy birds revealed no statistically significant differences. These findings indicate no association between the occurrence of MAS and enteric viruses. The viral genomes reported in the present study, including a variety of novel viruses, seem part of the normal intestinal microbiota of chickens.
The aim of this study was to investigate the microbial composition, and the profiles of antimicrobial resistance genes (ARGs, resistome) and mobile genetic elements (mobilome) of retail chicken ...carcasses originated from conventional intensive production systems (CO), certified antimicrobial-free intensive production systems (AF), and certified organic production systems with restricted antimicrobial use (OR). DNA samples were collected from 72 chicken carcasses according to a cross-sectional study design. Shot-gun metagenomics was performed by means of Illumina high throughput DNA sequencing followed by downstream bioinformatic analyses. Gammaproteobacteria was the most abundant bacterial class in all groups. Although CO, AF, and OR did not differ in terms of alpha- and beta-microbial diversity, the abundance of some taxa differed significantly across the groups, including spoilage-associated organisms such as Pseudomonas and Acinetobacter. The co-resistome comprised 29 ARGs shared by CO, AF and OR, including genes conferring resistance to beta-lactams (blaACT-8, 10, 13, 29; blaOXA-212;blaOXA-275 and ompA), aminoglycosides (aph(3′)-IIIa, VI, VIa and spd), tetracyclines (tet KL (W/N/W and M), lincosamides (inu A,C) and fosfomycin (fosA). ARGs were significantly less abundant (P < 0.05) in chicken carcasses from AF and OR compared with CO. Regarding mobile genetic elements (MGEs), transposases accounted for 97.2% of the mapped genes. A higher abundance (P = 0.037) of MGEs was found in CO compared to OR. There were no significant differences in ARGs or MGEs diversity among groups according to the Simpson´s index. In summary, retail frozen chicken carcasses from AF and OR systems show similar ARGs, MGEs and microbiota profiles compared with CO, even though the abundance of ARGs and MGEs was higher in chicken carcasses from CO, probably due to a higher selective pressure.
Inactivated polio vaccines (IPV) have an important role at the final stages of poliomyelitis eradication programs, reducing the risks associated with the use of attenuated polio vaccine (OPV). An ...affordable option to enhance vaccine immunogenicity and reduce costs of IPV may be the use of an effective and renewable adjuvant. In the present study, the adjuvant activity of aqueous extract (AE) and saponin fraction QB-90 from Quillaja brasiliensis using poliovirus antigen as model were analyzed and compared to a preparation adjuvanted with Quil-A, a well-known saponin-based commercial adjuvant. Experimental vaccines were prepared with viral antigen plus saline (control), Quil-A (50 µg), AE (400 µg) or QB-90 (50 µg). Sera from inoculated mice were collected at days 0, 28, 42 and 56 post-inoculation of the first dose of vaccine. Serum levels of specific IgG, IgG1 and IgG2a were significantly enhanced by AE, QB-90 and Quil-A compared to control group on day 56. The magnitude of enhancement was statistically equivalent for QB-90 and Quil-A. The cellular response was evaluated through DTH and analysis of IFN-γ and IL-2 mRNA levels using in vitro reestimulated splenocytes. Results indicated that AE and QB-90 were capable of stimulating the generation of Th1 cells against the administered antigen to the same extent as Quil-A. Mucosal immune response was enhanced by the vaccine adjuvanted with QB-90 as demonstrated by increases of specific IgA titers in bile, feces and vaginal washings, yielding comparable or higher titers than Quil-A. The results obtained indicate that saponins from Q. brasiliensis are potent adjuvants of specific cellular and humoral immune responses and represent a viable option to Quil-A.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Currently, fifteen bovine papillomavirus (BPV) types have been identified and classified into four genera: Deltapapillomavirus, Epsilonpapillomavirus, Dyoxipapillomavirus, and Xipapillomavirus. Here, ...the complete genome sequence of a new BPV type (BPV 04AC14) recovered from a papillomatous lesion is reported. The genome is 7,282 bp in length and exhibits the classic genetic organization and motifs of the members of Papillomaviridae. Maximum likelihood phylogenetic analyses revealed that BPV 04AC14 clusters with members of the Xipapillomavirus genus. The nucleotide sequence of the L1 capsid protein of the novel BPV is closely related to its counterpart, BPV3, with which it shares 79% similarity. These findings suggest that this virus is a new BPV type of the Xipapillomavirus genus.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The threat of viral influenza infections has sparked research efforts to develop vaccines that can induce broadly protective immunity with safe adjuvants that trigger robust immune responses. Here, ...we demonstrate that subcutaneous or intranasal delivery of a seasonal trivalent influenza vaccine (TIV) adjuvanted with the
saponin-based nanoparticle (IMXQB) increases the potency of TIV. The adjuvanted vaccine (TIV-IMXQB) elicited high levels of IgG2a and IgG1 antibodies with virus-neutralizing capacity and improved serum hemagglutination inhibition titers. The cellular immune response induced by TIV-IMXQB suggests the presence of a mixed Th1/Th2 cytokine profile, antibody-secreting cells (ASCs) skewed toward an IgG2a phenotype, a positive delayed-type hypersensitivity (DTH) response, and effector CD4
and CD8
T cells. After challenge, viral titers in the lungs were significantly lower in animals receiving TIV-IMXQB than in those inoculated with TIV alone. Most notably, mice vaccinated intranasally with TIV-IMXQB and challenged with a lethal dose of influenza virus were fully protected against weight loss and lung virus replication, with no mortality, whereas, among animals vaccinated with TIV alone, the mortality rate was 75%. These findings demonstrate that TIV-IMXQB improved the immune responses to TIV, and, unlike the commercial vaccine, conferred full protection against influenza challenge.
A study was conducted to investigate the serum virome of sows with and without stillbirths after farrowing. Sera from sows with at least one stillbirth or with normal litters were collected ...immediately after farrowing. Viral DNA was extracted from serum pools and submitted to high throughput sequencing. No differences in the proportion of virus-related reads were found in both groups (p > 0.05). A variety of viral DNA genomes were identified, mostly representative of three viral families: Anelloviridae, Circoviridae and Smacoviridae. Besides, a number of novel unclassified circular Rep-encoding single stranded DNA (CRESS DNA) viruses were also identified. These findings suggest that the presence of such viral genomes in sows' sera bears no correlation with stillbirths' occurrence; it seems likely that these constitute part of the normal serum microbiome of sows at farrowing.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
This study is focused on the identification of the faecal virome of healthy chickens raised in high-density, export-driven poultry farms in Brazil. Following high-throughput sequencing, a total of ...7743 de novo-assembled contigs were constructed and compared with known nucleotide/amino acid sequences from the GenBank database. Analyses with blastx revealed that 279 contigs (4 %) were related to sequences of eukaryotic viruses. Viral genome sequences (total or partial) indicative of members of recognized viral families, including Adenoviridae, Caliciviridae, Circoviridae, Parvoviridae, Picobirnaviridae, Picornaviridae and Reoviridae, were identified, some of those representing novel genotypes. In addition, a range of circular replication-associated protein encoding DNA viruses were also identified. The characterization of the faecal virome of healthy chickens described here not only provides a description of the viruses encountered in such niche but should also represent a baseline for future studies comparing viral populations in healthy and diseased chicken flocks. Moreover, it may also be relevant for human health, since chickens represent a significant proportion of the animal protein consumed worldwide.
Circoviruses are highly prevalent porcine and avian pathogens. In recent years, novel circular ssDNA genomes have recently been detected in a variety of fecal and environmental samples using deep ...sequencing approaches. In this study the identification of genomes of novel circoviruses and cycloviruses in feces of insectivorous bats is reported. Pan-reactive primers were used targeting the conserved rep region of circoviruses and cycloviruses to screen DNA bat fecal samples. Using this approach, partial rep sequences were detected which formed five phylogenetic groups distributed among the Circovirus and the recently proposed Cyclovirus genera of the Circoviridae. Further analysis using inverse PCR and Sanger sequencing led to the characterization of four new putative members of the family Circoviridae with genome size ranging from 1,608 to 1,790 nt, two inversely arranged ORFs, and canonical nonamer sequences atop a stem loop.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Vaccination is the most effective public health intervention to prevent influenza infections, which are responsible for an important burden of respiratory illnesses and deaths each year. Currently, ...licensed influenza vaccines are mostly split inactivated, although in order to achieve higher efficacy rates, some influenza vaccines contain adjuvants. Although split-inactivated vaccines induce mostly humoral responses, tailoring mucosal and cellular immune responses is crucial for preventing influenza infections. Quillaja brasiliensis saponin-based adjuvants, including ISCOM-like nanoparticles formulated with the QB-90 saponin fraction (IQB90), have been studied in preclinical models for more than a decade and have been demonstrated to induce strong humoral and cellular immune responses towards several viral antigens. Herein, we demonstrate that a split-inactivated IQB90 adjuvanted influenza vaccine triggered a protective immune response, stronger than that induced by a commercial unadjuvanted vaccine, when applied either by the subcutaneous or the intranasal route. Moreover, we reveal that this novel adjuvant confers up to a ten-fold dose-sparing effect, which could be crucial for pandemic preparedness. Last but not least, we assessed the role of caspase-1/11 in the generation of the immune response triggered by the IQB90 adjuvanted influenza vaccine in a mouse model and found that the cellular-mediated immune response triggered by the IQB90-Flu relies, at least in part, on a mechanism involving the casp-1/11 pathway but not the humoral response elicited by this formulation.
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