MDCK-SIAT1 cells show improved isolation rates for recent human influenza viruses compared to conventinal MDCK cells
- Authors: Oh, Ding , Barr, Ian , Mosse, Jennifer , Laurie, Karen
- Date: 2008
- Type: Text , Journal article
- Relation: Journal of Clinical Microbiology Vol. 46, no. 7 (2008), p. 2189-2194
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- Description: The ability to isolate and propagate influenza virus is an essential tool for the yearly surveillance of circulating virus strains and to ensure accurate clinical diagnosis for appropriate treatment. The suitability of MDCK-SIAT1 cells, engineered to express increased levels of alpha-2,6-linked sialic acid receptors, as an alternative to conventional MDCK cells for isolation of circulating influenza virus was assessed. A greater number of influenza A (H1N1 and H3N2) and B viruses from stored human clinical specimens collected between 2005 and 2007 were isolated following inoculation in MDCK-SIAT1 cells than in MDCK cells. In addition, a higher titer of virus was recovered following culture in MDCK-SIAT1 cells. All A(H1N1) viruses recovered from MDCK-SIAT1 cells were able to agglutinate both turkey and guinea pig red blood cells (RBC), while half of the A(H3N2) viruses recovered after passage in MDCK-SIAT1 cells lost the ability to agglutinate turkey RBC. Importantly, the HA-1 domain of the hemagglutinin gene was genetically stable after passaging in MDCK-SIAT1 cells, a feature not always seen following MDCK cell or embryonated chicken egg passage of human influenza virus. These data indicate that the MDCK-SIAT1 cell line is superior to conventional MDCK cells for isolation of human influenza virus from clinical specimens and may be used routinely for the isolation and propagation of current human influenza viruses for surveillance, diagnostic, and research purposes.
Potently immunosuppressive 5-fluorouracil-resistant mesenchymal stromal cells completely remit an experimental autoimmune disease
- Authors: Oh, Ding , Cui, Peng , Hosseini, Hamid , Mosse, Jennifer , Toh, Ban-Hock , Chan, Moh
- Date: 2012
- Type: Text , Journal article
- Relation: Journal Of Immunology Vol. 188, no. 5 (2012), p. 2207-2217
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- Description: We treated mice with 5-fluorouracil (5-FU) to isolate a quiescent and undifferentiated mesenchymal stromal cell (MSC) population from the bone marrow. We examined these 5-FU–resistant MSCs (5-FU–MSCs) free from hematopoietic components for CFU fibroblasts (CFU-Fs) and assessed their immunosuppressive potential in vitro and in vivo. We differentiated fibroblastic CFU-Fs (Fibro–CFU-Fs) from mixed CFU-Fs, based on the absence of in situ expression of CD11b and CD45 hematopoietic markers, as well as on their differentiation capacity. Fibro–CFU-Fs were associated with increased numbers of large-sized Fibro–CFU-Fs (≥9 mm2) that displayed enhanced capacity for differentiation into adipogenic and osteogenic mesenchymal lineages. Administration of these 5-FU–resistant CD11b−CD45− MSCs 6 d after myelin oligodendrocyte glycoprotein (MOG) immunization completely remitted MOG-induced experimental autoimmune encephalomyelitis after initial development of mild disease. The remission was accompanied by reduced CNS cellular infiltration and demyelination, as well as a significant reduction in anti-MOG Ab and splenocyte proliferation to MOG. MOG-stimulated splenocytes from these mice showed elevated levels of Th2 cytokines (IL-4, IL-5, and IL-6) and decreased IL-17. Compared with untreated MSCs, 5-FU–MSCs demonstrated potent immunosuppression of Con A-stimulated splenocytes in vitro, even at a 1:320 MSC/splenocyte ratio. Immunosuppression was accompanied by elevated IL-1ra, IL-10, and PGE2. Blocking IL-1ra, IL-10, and PGE2, but not IL-6, heme oxygenase-1, and NO, attenuated 5-FU–MSC–induced immunosuppression. Together, our findings suggested that immunosuppression by 5-FU-MSC is mediated by a combination of elevated IL-1ra, IL-10, and PGE2, anti-inflammatory Th2 cytokines, and decreased IL-17. Our findings suggested that 5-FU treatment identifies a population of potently immunosuppressive 5-FU–MSCs that have the potential to be exploited to remit autoimmune diseases.
A review of analytical techniques and their application in disease diagnosis in breathomics and salivaomics research
- Authors: Beale, David , Jones, Oliver , Karpe, Avinash , Dayalan, Saravanan , Oh, Ding , Kouremenos, Konstantinos , Ahmed, Warish , Palombo, Enzo
- Date: 2017
- Type: Text , Journal article
- Relation: International Journal of Molecular Sciences Vol. 18, no. 1 (2017), p. 1-26
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- Description: The application of metabolomics to biological samples has been a key focus in systems biology research, which is aimed at the development of rapid diagnostic methods and the creation of personalized medicine. More recently, there has been a strong focus towards this approach applied to non-invasively acquired samples, such as saliva and exhaled breath. The analysis of these biological samples, in conjunction with other sample types and traditional diagnostic tests, has resulted in faster and more reliable characterization of a range of health disorders and diseases. As the sampling process involved in collecting exhaled breath and saliva is non-intrusive as well as comparatively low-cost and uses a series of widely accepted methods, it provides researchers with easy access to the metabolites secreted by the human body. Owing to its accuracy and rapid nature, metabolomic analysis of saliva and breath (known as salivaomics and breathomics, respectively) is a rapidly growing field and has shown potential to be effective in detecting and diagnosing the early stages of numerous diseases and infections in preclinical studies. This review discusses the various collection and analyses methods currently applied in two of the least used non-invasive sample types in metabolomics, specifically their application in salivaomics and breathomics research. Some of the salient research completed in this field to date is also assessed and discussed in order to provide a basis to advocate their use and possible future scientific directions. © 2016 by the authors; licensee MDPI, Basel, Switzerland.
Using the ferret as an animal model for investigating influenza antiviral effectiveness
- Authors: Oh, Ding , Hurt, Aeron
- Date: 2016
- Type: Text , Journal article
- Relation: Frontiers in Microbiology Vol. 7, no. (2016), p. 1-12
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- Description: The concern of the emergence of a pandemic influenza virus has sparked an increased effort toward the development and testing of novel influenza antivirals. Central to this is the animal model of influenza infection, which has played an important role in understanding treatment effectiveness and the effect of antivirals on host immune responses. Among the different animal models of influenza, ferrets can be considered the most suitable for antiviral studies as they display most of the human-like symptoms following influenza infections, they can be infected with human influenza virus without prior viral adaptation and have the ability to transmit influenza virus efficiently between one another. However, an accurate assessment of the effectiveness of an antiviral treatment in ferrets is dependent on three major experimental considerations encompassing firstly, the volume and titer of virus, and the route of viral inoculation. Secondly, the route and dose of drug administration, and lastly, the different methods used to assess clinical symptoms, viral shedding kinetics and host immune responses in the ferrets. A good understanding of these areas is necessary to achieve data that can accurately inform the human use of influenza antivirals. In this review, we discuss the current progress and the challenges faced in these three major areas when using the ferret model to measure influenza antiviral effectiveness.
Selection of multi-drug resistant influenza A and B viruses under zanamivir pressure and their replication fitness in ferrets
- Authors: Oh, Ding , Panozzo, Jacqueline , Vitesnik, Sophie , Piedrafita, David , Mosse, Jennifer
- Date: 2018
- Type: Text , Journal article
- Relation: Antiviral Therapy Vol. 23, no. 4 (2018), p. 295-306
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- Description: Background: Intravenous zanamivir has been used to treat patients with severe influenza. Because the majority of cases (including immunocompromised patients) require the drug for an extended period of treatment, there is a higher risk that the virus will develop resistance. Therefore, knowing the possible amino acid substitutions that may arise in recently circulating influenza strains under prolonged zanamivir exposure and their impact on antiviral susceptibility is important. Methods: Influenza A(H1N1)pdm09, A(H3N2) and B virus were serially passaged under increasing zanamivir pressure in vitro. Neuraminidase (NA) mutations that arose were introduced into recombinant viruses and the susceptibility to oseltamivir, zanamivir, peramivir and laninamivir was determined. The replication fitness of the recombinant variants was assessed in the ferret. Results: NA mutations E119D (N1 numbering) and E117D (B numbering) were detected in A(H1N1)pdm09 and B (Victoria-lineage) viruses respectively and were associated with reduced susceptibility to all four NA inhibitors. No NA mutations were detected in the A(H3N2) or B (Yamagata-lineage) viruses. In ferrets, the A(H1N1) pdm09 E119D variant caused a lower degree of morbidity and the mutation was found to be unstable with E119 reverted virus detected 4 days post-infection of ferrets with the variant E119D virus. In contrast, the influenza B E117D variant was genetically stable in ferrets, caused a noticeable level of morbidity but had a significant reduction in replication fitness compared to wild-type virus. Conclusions: The NA mutations E119D in influenza A(H1N1)pdm09 and E117D in influenza B viruses that arose under zanamivir pressure conferred resistance to multiple NA inhibitors but had compromised viral replication in ferrets compared to wild-type virus without antiviral drug pressure. ©2018 International Medical Press. **Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “Jacqueline Panozzo, David Piedrafita, Jennifer Mosse” is provided in this record**