1.Characterisation of genotype VII Newcastle disease virus (NDV) isolated from NDV vaccinated chickens, and the efficacy of LaSota and recombinant genotype VII vaccines against challenge with velogenic NDV.
Kiarash ROOHANI ; Sheau Wei TAN ; Swee Keong YEAP ; Aini IDERIS ; Mohd Hair BEJO ; Abdul Rahman OMAR
Journal of Veterinary Science 2015;16(4):447-457
A Newcastle disease virus (NDV) isolate designated IBS002 was isolated from a commercial broiler farm in Malaysia. The virus was characterised as a virulent strain based on the multiple basic amino acid motif of the fusion (F) cleavage site 112RRRKGF117 and length of the C-terminus extension of the hemagglutinin-neuraminidase (HN) gene. Furthermore, IBS002 was classified as a velogenic NDV with mean death time (MDT) of 51.2 h and intracerebral pathogenicity index (ICPI) of 1.76. A genetic distance analysis based on the full-length F and HN genes showed that both velogenic viruses used in this study, genotype VII NDV isolate IBS002 and genotype VIII NDV isolate AF2240-I, had high genetic variations with genotype II LaSota vaccine. In this study, the protection efficacy of the recombinant genotype VII NDV inactivated vaccine was also evaluated when added to an existing commercial vaccination program against challenge with velogenic NDV IBS002 and NDV AF2240-I in commercial broilers. The results indicated that both LaSota and recombinant genotype VII vaccines offered full protection against challenge with AF2240-I. However, the LaSota vaccine only conferred partial protection against IBS002. In addition, significantly reduced viral shedding was observed in the recombinant genotype VII-vaccinated chickens compared to LaSota-vaccinated chickens.
Amino Acids, Basic
;
Animals
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Chickens*
;
Genetic Variation
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Genotype*
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Malaysia
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Newcastle disease virus*
;
Newcastle Disease*
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Vaccination
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Vaccines*
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Virulence
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Virus Shedding
2.Tumour Growth Inhibition and Systemic Responses of ΔsopBΔsopDΔpipD Disrupted Salmonella Agona and Salmonella Typhimurium in Mice
Ubaidah Naim Taraq Naem Zia ; Emy Sarah Ng Amar Ng ; Mohd Amirudin Sidik ; Mohamad Fauzi Mohd Idris ; Khoo Chai Hoon ; Sabrina Sukardi ; Yeap Swee Keong ; Cheah Yoke Kqueen
Malaysian Journal of Medicine and Health Sciences 2021;17(No.2):63-71
Introduction: Bacteria had long been known to have tumour-targeting and tumour inhibition capabilities and have
re-emerged into the limelight of cancer research as a possible alternative treatment for solid tumours. Conventional
therapies for solid tumours are either by surgery, chemotherapy, radiotherapy, which are very invasive and non-specific to the tumours and results in various adverse effects on the patients. Bacterial Mediated Tumour Therapy often
utilises attenuated bacteria as therapeutic agents to ensure reduced pathogenicity of the strains. However, this often
results in lower invasiveness towards the tumours itself. In this study, we studied the tumour inhibition capabilities
of Salmonella Pathogenicity Island (SPI) attenuated Salmonella Typhimurium (S. Typhimurium) and Salmonella Agona (S. Agona), specifically with attenuation of sopB, sopD, and pipD genes. Methods: Balb/c mice bearing CT26
tumours were inoculated with S. Typhimurium and S. Agona, both unattenuated and ΔsopBΔsopDΔpipD attenuated
strains. Tumour volumes were monitored daily. Organs and blood were collected for plasma liver enzyme analysis
and histopathology studies on testis, liver, kidneys and brain. Results: The ΔsopBΔsopDΔpipD S. Agona treated
group showed improved inhibition of tumour growth with 51.11% tumour volume reduction compared to unattenuated S. Agona. The ΔsopBΔsopDΔpipD strains have also shown lesser systemic effects as observed in plasma and
histopathological studies) compared to its unattenuated counterparts. Conclusion: The present study showed that
ΔsopBΔsopDΔpipD S. Agona has a great potential to be utilised as tumour therapeutic agent as it exerts lesser systemic effect while having similar tumour inhibition capabilities as the well-studied S. Typhimurium strain.