PATHOGENICITY, IMMUNOGENICITY, PROTECTION EFFICACY, AND SPIKE PROTEIN GENE SEQUENCE OF A HIGH-PASSAGE TURKEY CORONAVIRUS SERIALLY PASSAGED IN EMBRYONATED TURKEY EGGS

2018 ◽  
Vol 44 (04) ◽  
pp. 165-178
Author(s):  
Yi-Ning Chen ◽  
Ching Ching Wu ◽  
Tom Bryan ◽  
Tom Hooper ◽  
Donna Schrader ◽  
...  

Experimental infection of a high-passage turkey coronavirus passaged serially in embryonated turkey eggs for 344 times (P344 TCoV 540) showed no enteritis-related clinical signs, decreased body weight gains, gross, and microscopic lesions. TCoV spike (S) protein specific antibodies appeared from 14 days post infection (dpi) and increased gradually. Virus neutralization (VN) titers of the serum from P344 TCoV 540-inoculated turkeys were 1:13 at 14 dpi, 1:16 at 28 dpi, and 1:36 at 56 dpi against P344 TCoV 540. P344 TCoV 540-inoculated turkeys were protected against the challenge by homologous P344 TCoV 540 completely or low passage P3 TCoV 540 partially as revealed by lack of histopathological alterations, absence of TCoV by immunofluorescent antibody assay in the intestines, and reduction in TCoV viral RNA loads in the intestines and feces. The serum from P344 TCoV 540-vaccinated turkeys had higher VN titers against P344 TCoV 540 than those against P3 TCoV 540. P344 TCoV 540 had 52 amino acid substitutions as compared to those of P3 TCoV in the S protein. The results indicated that a high passage TCoV can induce protective humoral and cellular immune response and have potentials to become an attenuated vaccine.

2005 ◽  
Vol 86 (5) ◽  
pp. 1435-1440 ◽  
Author(s):  
Milosz Faber ◽  
Elaine W. Lamirande ◽  
Anjeanette Roberts ◽  
Amy B. Rice ◽  
Hilary Koprowski ◽  
...  

Foreign viral proteins expressed by rabies virus (RV) have been shown to induce potent humoral and cellular immune responses in immunized animals. In addition, highly attenuated and, therefore, very safe RV-based vectors have been constructed. Here, an RV-based vaccine vehicle was utilized as a novel vaccine against severe acute respiratory syndrome coronavirus (SARS-CoV). For this approach, the SARS-CoV nucleocapsid protein (N) or envelope spike protein (S) genes were cloned between the RV glycoprotein G and polymerase L genes. Recombinant vectors expressing SARS-CoV N or S protein were recovered and their immunogenicity was studied in mice. A single inoculation with the RV-based vaccine expressing SARS-CoV S protein induced a strong SARS-CoV-neutralizing antibody response. The ability of the RV-SARS-CoV S vector to confer immunity after a single inoculation makes this live vaccine a promising candidate for eradication of SARS-CoV in animal reservoirs, thereby reducing the risk of transmitting the infection to humans.


2019 ◽  
Vol 20 (10) ◽  
pp. 2379 ◽  
Author(s):  
Johannes Fels ◽  
Bettina Scharner ◽  
Ralf Zarbock ◽  
Itzel Pamela Zavala Guevara ◽  
Wing-Kee Lee ◽  
...  

Cadmium (Cd2+) in the environment is a significant health hazard. Chronic low Cd2+ exposure mainly results from food and tobacco smoking and causes kidney damage, predominantly in the proximal tubule. Blood Cd2+ binds to thiol-containing high (e.g., albumin, transferrin) and low molecular weight proteins (e.g., the high-affinity metal-binding protein metallothionein, β2-microglobulin, α1-microglobulin and lipocalin-2). These plasma proteins reach the glomerular filtrate and are endocytosed at the proximal tubule via the multiligand receptor complex megalin:cubilin. The current dogma of chronic Cd2+ nephrotoxicity claims that Cd2+-metallothionein endocytosed via megalin:cubilin causes renal damage. However, a thorough study of the literature strongly argues for revision of this model for various reasons, mainly: (i) It relied on studies with unusually high Cd2+-metallothionein concentrations; (ii) the KD of megalin for metallothionein is ~105-times higher than (Cd2+)-metallothionein plasma concentrations. Here we investigated the uptake and toxicity of ultrafiltrated Cd2+-binding protein ligands that are endocytosed via megalin:cubilin in the proximal tubule. Metallothionein, β2-microglobulin, α1-microglobulin, lipocalin-2, albumin and transferrin were investigated, both as apo- and Cd2+-protein complexes, in a rat proximal tubule cell line (WKPT-0293 Cl.2) expressing megalin:cubilin at low passage, but is lost at high passage. Uptake was determined by fluorescence microscopy and toxicity by MTT cell viability assay. Apo-proteins in low and high passage cells as well as Cd2+-protein complexes in megalin:cubilin deficient high passage cells did not affect cell viability. The data prove Cd2+-metallothionein is not toxic, even at >100-fold physiological metallothionein concentrations in the primary filtrate. Rather, Cd2+-β2-microglobulin, Cd2+-albumin and Cd2+-lipocalin-2 at concentrations present in the primary filtrate are taken up by low passage proximal tubule cells and cause toxicity. They are therefore likely candidates of Cd2+-protein complexes damaging the proximal tubule via megalin:cubilin at concentrations found in the ultrafiltrate.


2020 ◽  
Vol 32 (3) ◽  
pp. 409-412
Author(s):  
Laurete Murer ◽  
Marília B. Ribeiro ◽  
Glaucia D. Kommers ◽  
Mauro P. Soares ◽  
Juliana F. Cargnelutti ◽  
...  

We diagnosed disease caused by psittacid herpesvirus 3 (PsHV-3), a novel psittacid pathogen, in rose-ringed parakeets ( Psittacula krameri) housed in an exotic psittacine breeding colony in southern Brazil. The disease affected several adult birds. Clinical signs included apathy, tachypnea, and wheezing. Four birds were autopsied, and sections of lungs and liver were examined histologically and by electron microscopy (EM), revealing pulmonary congestion, bronchopneumonia, or multifocal necrosis of tertiary bronchi, with syncytial cells and eosinophilic intranuclear inclusion bodies. Viral particles morphologically compatible with herpesviruses were observed by EM in lung sections. PCR with pan-herpesvirus primers performed on total DNA extracted from paraffinized tissue resulted in a 278-bp product. Sequencing of the amplicon revealed 93% nucleotide identity with a PsHV-3 sequence available in GenBank. Phylogenetic analysis grouped the obtained sequence with the only PsHV-3 DNA polymerase gene sequence available (GenBank accession JX028240) and separated the sequence from psittacid herpesviruses 1 and 2. The clinical, pathologic, and molecular findings support the association of PsHV-3 with pneumonia found in these rose-ringed parakeets in southern Brazil.


Vaccines ◽  
2020 ◽  
Vol 8 (4) ◽  
pp. 762
Author(s):  
Yuanling Bao ◽  
Mengmeng Yu ◽  
Peng Liu ◽  
Fujun Hou ◽  
Farooque Muhammad ◽  
...  

Avian metapneumovirus (aMPV), a highly contagious agent, is widespread and causes acute upper respiratory tract disease in chickens and turkeys. However, currently, there is no vaccine licensed in China. Herein, we describe the development of an inactivated aMPV/B vaccine using the aMPV/B strain LN16. Combined with a novel adjuvant containing immune-stimulating complexes (ISCOMs), the novel vaccine could induce high virus-specific and VN antibodies. In addition, it activated B and T lymphocytes and promoted the expression of IL-4 and IFN-γ. Importantly, boosting vaccination with the inactivated aMPV/B vaccine could provide 100% protection against aMPV/B infection with reduced virus shedding and turbinate inflammation. The protection efficacy could last for at least 6 months. This study yielded a novel inactivated aMPV/B vaccine that could serve as the first vaccine candidate in China, thus contributing to the control of aMPV/B and promoting the development of the poultry industry.


Parasitology ◽  
2006 ◽  
Vol 133 (4) ◽  
pp. 421-432 ◽  
Author(s):  
P. M. BARTLEY ◽  
S. WRIGHT ◽  
J. SALES ◽  
F. CHIANINI ◽  
D. BUXTON ◽  
...  

To determine whether prolonged in vitro passage would result in attenuation of virulence in vivo, Neospora caninum tachyzoites were passaged for different lengths of time in vitro and compared for their ability to cause disease in mice. Groups of Balb/c mice were inoculated intraperitoneally with 5×106 or 1×107 of low-passage or high-passage N. caninum tachyzoites. The mice were monitored for changes in their demeanour and body weight, and were culled when severe clinical symptoms of murine neosporosis were observed. Mice inoculated with the high-passage parasites survived longer (P<0·05), and showed fewer clinical symptoms of murine neosporosis, compared to the mice receiving the low-passage parasites. The parasite was detected in the brains of inoculated mice using immunohistochemistry and ITS1 PCR. Tissue cysts containing parasites were seen in mice inoculated with both low-passage and high-passage parasites. When the in vitro growth rates of the parasites were compared, the high-passage parasites initially multiplied more rapidly (P<0·001) than the low-passage parasites, suggesting that the high-passage parasites had become more adapted to tissue culture. These results would suggest that it is possible to attenuate the virulence of N. caninum tachyzoites in mice through prolonged in vitro passage.


1965 ◽  
Vol 11 (3) ◽  
pp. 435-439 ◽  
Author(s):  
John Furesz ◽  
Pierre Moreau

BS-C-1 cells, cultivated in a simple medium designated M-E, were found to be suitable for a plaque assay of polio and measles viruses. In the plaque assay both low- and high-passage levels of the BS-C-1 cell line were highly susceptible to measles virus but titers of polioviruses were lower in the high-passage cells. Low-passage cells, preserved and stored at −196 °C for prolonged periods, are recommended for the titration of polio and measles viruses.


Sign in / Sign up

Export Citation Format

Share Document