Aviadenovirus

2018

PLoS ONE

BackgroundTo date, studies on loop L1 HVRs1-4 region of the hexon gene in fowl adenovirus genome (FAdVs) lack comprehensive molecular data. In this study detailed prospectively obtained sequences from field adenovirus strains, NVRI, Poland have been analyzed.MethodsOverall hundred and thirty seven adenovirus strains were collected, evaluated, and examined of hyper variable loop L1 region HVRs1-4 of the hexon gene for the presence of similarity, mutations, tertiary structure, and spinal conformation.ResultsSequences were characterized, and divided for five species and seven types, FAdV-A-E/FAdV-1/2/4/5/7/8a/8b/11. The presence of predicted tertiary structure depending on type/species were determined. Analysis of specific selected sequences: GQMTN 1/A, 7/E, and 8b/E, GQMTT 2/11/D, GQLSN 4/C, GQMTH 5/B, and GQMSN 8a/E in examined HVRs1-4 Loop L1 region of hexon gene compared to tertiary structure indicated that this visibly conservative region represents the antigenic binging activity.ConclusionThis is the first molecular study on tertiary structure on HVRs1-4 region in adenovirus genome conducted in Poland. Analysis indicated specific sequence in Loop L1 HVR1-4 region which is strictly responsible for antibodies binding. This information could assist during the process connected with specific preventive strategies based on their molecular genome investigation and new facilitate studies. This study will help to better understand the mechanisms of pathogenicity of adenovirus strains provide a guide for disease control in birds.

Section: Resultsmentioning

confidence: 99%

Deep analysis of Loop L1 HVRs1-4 region of the hexon gene of adenovirus field strains isolated in Poland

2018

PLoS ONE

“…To date, the mechanisms of adenovirus pathogenicity are not well understood [13]. Strains of the same type or species can have different pathogenicity.…”

Section: Discussionmentioning

confidence: 99%

A comparative pathogenicity analysis of two adenovirus strains, 1/A and 8a/E, isolated from poultry in Poland

Czekaj

2018

Arch Virol

Fowl adenoviruses (FAdVs) are the causative agents of multietiological syndromes and diseases in poultry flocks. During a routine diagnostic examination, two FAdVs strains were isolated. Molecular typing of these isolates based on the partial loop L1 HVR1-4 region of the hexon gene sequence revealed the presence of different FAdV isolates: 1/A-61/11z (GenBank accession number KX247012, APP94082), and 8a/E-6/12j (GenBank accession number: KP890032, ALB00550), and comparative genome analysis indicated small differences between these two viruses. The next step of the study was the estimation of the pathogenicity of these isolates in specific-pathogen-free (SPF) chickens. Chickens were divided into three groups, with 20 chickens per group infected intraperitoneally on the first day after hatching. Group I consisted of chickens infected with strain FAdV-1/A-61/11z, group II consisted of chickens infected with strain FAdV-8a/E-6/12j, and group III consisted of uninfected birds. Clinical signs observed in infected chickens included poor growth, apathy, prostration, ruffled feathers, crouching position, and huddling behavior. The mortality rate in chickens infected with FAdV-1/A-61/11z was 10% at 10 days postinfection (dpi), and no mortality was observed in chickens infected with the FAdV-8a-6/12j strain. The mean real-time PCR threshold cycle (Ct) value was 39.70%. The detection limit of these assays was 8 copies, with an efficiency of 91.03% and 95.17% and regression square (R2) values of 0.991 and 0.997, respectively, with a mean pathogen load of 4.8 × 10 6.0 copies/µl. The assays did not demonstrate cross-reactivity between types 1/A and 8a/E and non-targeted poultry viruses. Adenoviral DNA was detected in the liver, spleen, kidney, gizzard, intestine, bursa of Fabricius, and thymus of every examined dead and euthanized chicken from groups I and II between the third and fourth week postinfection. This is the first study conducted on the pathogenic and apathogenic strains FAdV-1/A and FAdV-8a/E, showing the presence of the virus in multiple tissues in chickens in Poland. This study revealed that it is very likely that the FAdV-1/A-61/11z strain is able to cause clinical inclusion body hepatitis (IBH) in chickens and that it is slightly more virulent than the FAdV-8a/E-6/12j strain, although both are primary pathogens of the disease.

“…The pathogenic role of the aviadenoviruses is not clear enough. They can be isolated from both sick birds, and birds without any signs of illness (12,16). The role of adenoviruses as the opportunistic factors is indicated (7).…”

Section: Introductionmentioning

confidence: 99%

Analysis of adenovirus strains isolated from poultry in Poland

Bulletin of the Veterinary Institute in Pulawy

Samorek-Salamonowicz

Czekaj

2013

The study describes successful isolation of 96 fowl adenovirus (FAdV) strains from 789 chickens from 95 flocks. PCR specific for hexon gene encoding L1 loop was conducted. Amplicons were subjected to sequence analysis. The sequences were analysed by the software: BLAST, Geneious 6.0, and MEGA 5, then aligned with different adenovirus strain reference sequences accessible in GenBank database. The examined strains belong to the particular groups and serotypes. The sequences of all adenoviruses were classified into five species (FAdV A-E) and eight serotypes .