Full genome sequence-based comparative study of wild-type and vaccine strains of infectious laryngotracheitis virus from Italy

Infectious laryngotracheitis (ILT) is an acute and highly contagious respiratory disease of chickens caused by an alphaherpesvirus, infectious laryngotracheitis virus (ILTV). Recently, full genome sequences of wild-type and vaccine strains have been determined worldwide, but none was from Europe. The aim of this study was to determine and analyse the complete genome sequences of five ILTV strains. Sequences were also compared to reveal the similarity of strains across time and to discriminate between wild-type and vaccine strains. Genomes of three ILTV field isolates from outbreaks occurred in Italy in 1980,2007 and 2011, and two commercial chicken embryo origin (CEO) vaccines were sequenced using the 454 Life Sciences technology. The comparison with the Serva genome showed that 35 open reading frames (ORFs) differed across the five genomes. Overall, 54 single nucleotide polymorphisms (SNPs) and 27 amino acid differences in 19 ORFs and two insertions in the UL52 and ORFC genes were identified. Similarity among the field strains and between the field and the vaccine strains ranged from 99.96% to 99.99%. Phylogenetic analysis revealed a close relationship among them, as well. This study generated data on genomic variation among Italian ILTV strains revealing that, even though the genetic variability of the genome is well conserved across time and between wild-type and vaccine strains, some mutations may help in differentiating among them and maybe involved in ILTV virulence/attenuation. The results of this study can contribute to the understanding of the molecular bases of ILTV pathogenicity and provide genetic markers to differentiate between wild-type and vaccine strains

Viral proteins expressed in the protozoan parasite Eimeria tenella are detected by the chicken immune system

BACKGROUND: Eimeria species are parasitic protozoa that cause coccidiosis, an intestinal disease commonly characterised by malabsorption, diarrhoea and haemorrhage that is particularly important in chickens. Vaccination against chicken coccidiosis is effective using wild-type or attenuated live parasite lines. The development of protocols to express foreign proteins in Eimeria species has opened up the possibility of using Eimeria live vaccines to deliver heterologous antigens and function as multivalent vaccine vectors that could protect chickens against a range of pathogens. RESULTS: In this study, genetic complementation was used to express immunoprotective virus antigens in Eimeria tenella. Infectious bursal disease virus (IBDV) causes Gumboro, an immunosuppressive disease that affects productivity and can interfere with the efficacy of poultry vaccination programmes. Infectious laryngotracheitis virus (ILTV) causes a highly transmissible respiratory disease for which strong cellular immunity and antibody responses are required for effective vaccination. Genes encoding the VP2 protein from a very virulent strain of IBDV (vvVP2) and glycoprotein I from ILTV (gI) were cloned downstream of 5’Et-Actin or 5’Et-TIF promoter regions in plasmids that also contained a mCitrine fluorescent reporter cassette under control of the 5’Et-MIC1 promoter. The plasmids were introduced by nucleofection into E. tenella sporozoites, which were then used to infect chickens. Progeny oocysts were sorted by FACS and passaged several times in vivo until the proportion of fluorescent parasites in each transgenic population reached ~20 % and the number of transgene copies per parasite genome decreased to < 10. All populations were found to transcribe and express the transgene and induced the generation of low titre, transgene-specific antibodies when used to immunise chickens. CONCLUSIONS: E. tenella can express antigens of other poultry pathogens that are successfully recognised by the chicken immune system. Nonetheless, further work has to be done in order to improve the levels of expression for its future use as a multivalent vaccine vector. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13071-016-1756-2) contains supplementary material, which is available to authorized users

Molecular techniques for diagnosis of animal deseases

Infectious laryngotracheitis (ILT) is an acute respiratory disease transmitted through respiratory secretions or fomites from naturally infected birds or the use of live vaccines. We investigated an outbreak of respiratory disease occurred in 2011 in Ecuador, a country where the disease was regarded as exotic. Viral detection was carried out by PCR (genes ICP4 and TK) and partial viral characterization was accomplished by amplicon sequencing. Our results suggested that the outbreak was caused by a field strain of ILTV

Pulmonary embolectomy in a patient with recent renal homotransplantation

A successful case of pulmonary embolectomy is described. Diagnosis was made when the patient developed cardiac arrest in the hospital ward. The embolus was removed with the aid of cardiopulmonary bypass. The principal clot was discovered in the right pulmonary artery, with an additional small fragment in the left main pulmonary artery. Several unique features of this case increased the problems of care during and after the embolectomy. The patient had received a renal homotransplant to the left iliac fossa from a patient of a different blood type 7 weeks earlier. The embolus was thought to have originated in the left leg distal to the renal vein anastomosis. Technical details of the cardiopulmonary bypass and the subsequent vena caval plication were planned with a view to protecting the function of the graft. The presence of the renal homograft may have contributed to the original formation of the peripheral thrombus. Finally, the postoperative care was complicated by the need to provide cytotoxic drug therapy for the continued protection of the homograft. This therapy, which weakens the immunologic response of the host, had to be modified when septic complications occurred during the postoperative period. Eventual recovery was possible with minimal loss of renal function. © 1964

Laringotracheite Infettiva Aviaria: gestione dei focolai nel Nord Italia

La Laringotracheite infettiva (ILT) è un’infezione respiratoria di origine virale che colpisce frequentemente i polli (gallus gallus). Tale patologia riveste una grande importanza nel contesto dell’allevamento avicolo industriale alla luce dei severi danni economici che è in grado di apportare al settore a causa della forte mortalità e dello spiccato calo dell’ovodeposizione. The infectious laryngotracheitis (ILT) is a respiratory infection caused by a virus that commonly affects chickens (Gallus gallus). This disease is of great importance in the context of poultry farms in the light of industrial severe economic damage that is able to bring to the industry due to the high mortality and the marked decrease of laying

Review of the Molecular Biology and Epidemiology of Infectious Laryngotracheitis (Gallid Herpesvirus-1)

A review of the molecular biology and epidemiology of avian infectious laryngotracheitis (ILT) is conducted due to the outdated state of current ILT review material. The objective of this review is to include updated information on the molecular biology of Gallid herpesvirus 1 (GaHV-1), the causative agent of ILT, and to present the latest information on the molecular epidemiology of ILT. Recent developments in molecular biology specific to GaHV-1 have been made and are highlighted in this review, and the role of current and historical use of live-attenuated vaccines is associated with the global and molecular epidemiology of ILT. Also, target genes for detection and strain differentiation are compiled by region of the world, and the global distribution of ILT is illustrated. Additionally, the field of epigenetics related to virus-host interactions is reviewed, and the molecular, epidemiologic, and epigenetic factors investigated are related to prospects for future eradication of ILT

Comparision of different cell cultures for replication of infectious laryngotracheitis virus from chickens

The propagation of infectious laryngotracheitis virus (ILTV) has been described using primary cell cultures derived from chicken embryo liver and kidney or embryonated eggs, but these cultures use Specific Pathogen Free (SPF) eggs that are time and cost expensive. Since cell line cultures are easier to maintain in laboratory conditions, the growth of ILTV was evaluated in five different cell cultures: chicken embryo related cells (CER), a cell hybrid derived from chicken embryo fibroblasts cells and BHK-21; Vero, from African green monkey kidney cells; HD11, a chicken macrophage cell line; CEC-32, an avian fibroblast cell line and a primary cell culture of chicken embryo fibroblasts (CEF). Cytophatic effect was observed until 96 hours following inoculation and the detection of the viral DNA was performed by PCR. The HD11 and CEC-32 cell lines did not support the virus growth but CEF and Vero, as already described were permissive cultures for propagation of ILTV.The results also showed that the CER cell line can be used for primary isolation and replication of ILTV

The role of the bursa of Fabricius in the development of resistance in infectious laryngotracheitis

Call number: LD2668 .T4 1956 B36Master of Scienc

Genotyping of Infectious Laryngotracheitis Virus (ILTV) isolates from Western Canadian provinces of Alberta and British Columbia based on partial Open Reading Frame (ORF) a and b

Infectious laryngotracheitis virus (ILTV) causes an acute upper respiratory disease in chickens called infectious laryngotracheitis (ILT). Live attenuated vaccines are effective in disease control; however, they have residual virulence, which makes them able to replicate, cause disease and revert to the original virulent form. Information is scarce on the molecular nature of ILTV that is linked to ILT in Canada. This study aims to determine whether isolates originating from ILT cases in Western Canada are a wild type or vaccine origin. Samples submitted for the diagnosis of ILT between 2009–2018 were obtained from Alberta (AB, n = 46) and British Columbia (BC, n = 9). For genotyping, a Sanger sequencing of open reading frame (ORF) a and b was used. A total of 27 from AB, and 5 from BC samples yielded a fragment of 1751 base pairs (bp). Three of the BC samples classified as group IV (CEO vaccine strains) and 2 as group V (CEO revertant). Of the AB samples, 22 samples clustered with group V, 3 with group VI (wild type), and 2 with group VII, VIII, and IX (wild type). Overall, 17 non-synonymous single nucleotide polymorphisms (SNPs) were detected. Further studies are underway to ascertain the virulence and transmission potential of these isolates