Immune Diagnostics and Research

Toronto, Canada

Immune Diagnostics and Research

Toronto, Canada

Time filter

Source Type

Paquette S.G.,Toronto General Research Institute | Paquette S.G.,University of Toronto | Banner D.,Toronto General Research Institute | Zhao Z.,Shantou University | And 31 more authors.
PLoS ONE | Year: 2012

Pandemic H1N1 influenza A (H1N1pdm) is currently a dominant circulating influenza strain worldwide. Severe cases of H1N1pdm infection are characterized by prolonged activation of the immune response, yet the specific role of inflammatory mediators in disease is poorly understood. The inflammatory cytokine IL-6 has been implicated in both seasonal and severe pandemic H1N1 influenza A (H1N1pdm) infection. Here, we investigated the role of IL-6 in severe H1N1pdm infection. We found IL-6 to be an important feature of the host response in both humans and mice infected with H1N1pdm. Elevated levels of IL-6 were associated with severe disease in patients hospitalized with H1N1pdm infection. Notably, serum IL-6 levels associated strongly with the requirement of critical care admission and were predictive of fatal outcome. In C57BL/6J, BALB/cJ, and B6129SF2/J mice, infection with A/Mexico/4108/2009 (H1N1pdm) consistently triggered severe disease and increased IL-6 levels in both lung and serum. Furthermore, in our lethal C57BL/6J mouse model of H1N1pdm infection, global gene expression analysis indicated a pronounced IL-6 associated inflammatory response. Subsequently, we examined disease and outcome in IL-6 deficient mice infected with H1N1pdm. No significant differences in survival, weight loss, viral load, or pathology were observed between IL-6 deficient and wild-type mice following infection. Taken together, our findings suggest IL-6 may be a potential disease severity biomarker, but may not be a suitable therapeutic target in cases of severe H1N1pdm infection due to our mouse data. © 2012 Paquette et al.

Cameron M.J.,Toronto General Research Institute | Cameron M.J.,University of Toronto | Kelvin A.A.,Immune Diagnostics and Research | Leon A.J.,Toronto General Research Institute | And 27 more authors.
PLoS ONE | Year: 2012

In terms of its highly pathogenic nature, there remains a significant need to further define the immune pathology of SARS-coronavirus (SARS-CoV) infection, as well as identify correlates of immunity to help develop vaccines for severe coronaviral infections. Here we use a SARS-CoV infection-reinfection ferret model and a functional genomics approach to gain insight into SARS immunopathogenesis and to identify correlates of immune protection during SARS-CoV-challenge in ferrets previously infected with SARS-CoV or immunized with a SARS virus vaccine. We identified gene expression signatures in the lungs of ferrets associated with primary immune responses to SARS-CoV infection and in ferrets that received an identical second inoculum. Acute SARS-CoV infection prompted coordinated innate immune responses that were dominated by antiviral IFN response gene (IRG) expression. Reinfected ferrets, however, lacked the integrated expression of IRGs that was prevalent during acute infection. The expression of specific IRGs was also absent upon challenge in ferrets immunized with an inactivated, Al(OH)3-adjuvanted whole virus SARS vaccine candidate that protected them against SARS-CoV infection in the lungs. Lack of IFN-mediated immune enhancement in infected ferrets that were previously inoculated with, or vaccinated against, SARS-CoV revealed 9 IRG correlates of protective immunity. This data provides insight into the molecular pathogenesis of SARS-CoV and SARS-like-CoV infections and is an important resource for the development of CoV antiviral therapeutics and vaccines. © 2012 Cameron et al.

Kelvin A.A.,University of Sassari | Kelvin A.A.,Immune Diagnostics and Research | Meloni D.,University of Sassari | Sansonetti P.,University of Sassari | And 10 more authors.
Journal of Infection in Developing Countries | Year: 2012

Introduction: Wild migratory birds are global distributors of pathogens. Sardinia, Italy, is the second largest Island in the Mediterranean and is a land bridge between Europe and Africa. Methodology: We designed a surveillance protocol to investigate wild migratory birds for presence, frequency, and type of avian influenza viruses. We collected over 4,000 avian samples and compared three sampling methods, fecal, cloacal, and tracheal, to determine the most productive for virus identification. To determine frequency of infection, RNA was extracted and RT-PCRs for avian influenza virus genes were run. Positive samples were cultivated for live virus, sub typed and sequenced. Results: Forty-four samples were positive for influenza nucleoprotein gene. We identified two previously unidentified H3 subtype strains and found cloacae to have the highest rate of virus identification and fecal sampling to provide quality RNA and repeatable results for determination of virus presence. Conclusion: Our investigation provides information on the frequency of Mediterranean avian influenza viruses, and validates the initiation of an avian influenza surveillance protocol. Taken together with global avian influenza findings, these results give insight into infectious disease distributions which is important for viral pandemic monitoring and design of preventative measures. © 2012 Kelvin et al.

Huang S.S.H.,Toronto General Research Institute | Banner D.,Toronto General Research Institute | Banner D.,University of Toronto | Paquette S.G.,Toronto General Research Institute | And 7 more authors.
Journal of General Virology | Year: 2014

Influenza B viruses have become increasingly more prominent during influenza seasons. Influenza B infection is typically considered a mild disease and receives less attention than influenza A, but has been causing 20 to 50% of the total influenza incidence in several regions around the world. Although there is increasing evidence of mid to lower respiratory tract diseases such as bronchitis and pneumonia in influenza B patients, little is known about the pathogenesis of recent influenza B viruses. Here we investigated the clinical and pathological profiles of infection with strains representing the two current co-circulating B lineages (B/Yamagata and B/Victoria) in the ferret model. Specifically, we studied two B/Victoria (B/Brisbane/60/2008 and B/Bolivia/1526/2010) and two B/Yamagata (B/Florida/04/2006 and B/Wisconsin/01/2010) strain infections in ferrets and observed strain-specific but not lineage-specific pathogenicity. We found B/Brisbane/60/ 2008 caused the most severe clinical illness and B/Brisbane/60/2008 and the B/Yamagata strains instigated pathology in the middle to lower respiratory tract. Importantly, B/Brisbane/60/2008 established efficient lower respiratory tract infection with high viral burden. Our phylogenetic analyses demonstrate profound reassortment among recent influenza B viruses, which indicates the genetic make-up of B/Brisbane/60/2008 differs from the other strains. This may explain the pathogenicity difference post-infection in ferrets. © 2014 The Authors.

Paquette S.G.,Toronto General Research Institute | Paquette S.G.,University of Toronto | Huang S.S.H.,Toronto General Research Institute | Huang S.S.H.,University of Toronto | And 9 more authors.
Virology | Year: 2014

The major burden of influenza morbidity resides within the elderly population. The challenge managing influenza-associated illness in the elderly is the decline of immune function, where mechanisms leading to immunological senescence have not been elucidated. To better represent the immune environment, we investigated clinical morbidity and immune function during sequential homologous and heterologous H1N1 influenza infection in an aged ferret model. Our findings demonstrated experimentally that aged ferrets had significant morbidity during monosubtypic heterologous 2° challenge with significant weight loss and respiratory symptoms. Furthermore, increased clinical morbidity was associated with slower and shorter hemagglutinin antibody generation and attenuated type 1 T-cell gene responses in peripheral blood. These results revealed dampened immune activation during sequential influenza infection in aged ferrets. With the presence of an aged model, dissecting clinical morbidity, viral dynamics and immune response during influenza infection will aid the development of future prophylactics such as age specific influenza vaccines. © 2014 The Authors. Published by Elsevier Inc.

Sidahmed A.M.E.,Toronto General Research Institute | Sidahmed A.M.E.,University of Toronto | Leon A.J.,Toronto General Research Institute | Leon A.J.,Shantou University | And 10 more authors.
Journal of Infection in Developing Countries | Year: 2014

Introduction: Chemokines are small proteins that regulate different cellular functions, such as leukocyte activation, chemoattraction and inflammation. The chemokine CXCL14 (BRAK) is a highly conserved gene among species and through evolution. It has been shown that CXCL14 is locally upregulated during viral infections, also, it has been found that this chemokine possesses direct antibacterial activities. Nonetheless, the exact role that CXCL14 plays during infection remains elusive.Methodology: CXCL14 deficient mice were generated in a C57B6/129 background and followed by phenotypic characterization. Later, the effect of CXCL14 deficiency during influenza infection and E. coli challenge was assessed.Results: Other than a slight weight reduction, CXCL14 deficient mice exhibited no phenotypic alterations. CXCL14 deficiency did not influence the outcome of influenza virus infection or challenge with E. coli, and no statistically significant differences in clinical signs, cellular responses and histopathological findings were observed.Conclusions: CXCL14 does not seem to play a pivotal role during influenza and E. coli infections of the lung; these results are suggestive of functional overlap between CXCL14 and other chemokines that are present during lung infection. © 2014 Sidahmed et al.

Huang S.S.H.,Toronto General Research Institute | Huang S.S.H.,University of Toronto | Lin Z.,Toronto General Research Institute | Lin Z.,Shantou University | And 13 more authors.
Scientific Reports | Year: 2013

Evolution of H1N1 influenza A outbreaks of the past 100 years is interesting and significantly complex and details of H1N1 genetic drift remains unknown. Here we investigated the clinical characteristics and immune cross-reactivity of significant historical H1N1 strains. We infected ferrets with H1N1 strains from 1943, 1947, 1977, 1986, 1999, and 2009 and showed each produced a unique clinical signature. We found significant cross-reactivity between viruses with similar HA sequences. Interestingly, A/FortMonmouth/1/1947 antisera cross-reacted with A/USSR/90/1977 virus, thought to be a 1947 resurfaced virus. Importantly, our immunological data that didn't show cross-reactivity can be extrapolated to failure of past H1N1 influenza vaccines, ie. 1947, 1986 and 2009. Together, our results help to elucidate H1N1 immuno-genetic alterations that occurred in the past 100 years and immune responses caused by H1N1 evolution. This work will facilitate development of future influenza therapeutics and prophylactics such as influenza vaccines.

Huang S.S.H.,Toronto General Research Institute | Huang S.S.H.,University of Toronto | Banner D.,Toronto General Research Institute | Fang Y.,Toronto General Research Institute | And 9 more authors.
PLoS ONE | Year: 2011

Influenza A and B infections are a worldwide health concern to both humans and animals. High genetic evolution rates of the influenza virus allow the constant emergence of new strains and cause illness variation. Since human influenza infections are often complicated by secondary factors such as age and underlying medical conditions, strain or subtype specific clinical features are difficult to assess. Here we infected ferrets with 13 currently circulating influenza strains (including strains of pandemic 2009 H1N1 [H1N1pdm] and seasonal A/H1N1, A/H3N2, and B viruses). The clinical parameters were measured daily for 14 days in stable environmental conditions to compare clinical characteristics. We found that H1N1pdm strains had a more severe physiological impact than all season strains where pandemic A/California/07/2009 was the most clinically pathogenic pandemic strain. The most serious illness among seasonal A/H1N1 and A/H3N2 groups was caused by A/Solomon Islands/03/2006 and A/Perth/16/2009, respectively. Among the 13 studied strains, B/Hubei-Wujiagang/158/2009 presented the mildest clinical symptoms. We have also discovered that disease severity (by clinical illness and histopathology) correlated with influenza specific antibody response but not viral replication in the upper respiratory tract. H1N1pdm induced the highest and most rapid antibody response followed by seasonal A/H3N2, seasonal A/H1N1 and seasonal influenza B (with B/Hubei-Wujiagang/158/2009 inducing the weakest response). Our study is the first to compare the clinical features of multiple circulating influenza strains in ferrets. These findings will help to characterize the clinical pictures of specific influenza strains as well as give insights into the development and administration of appropriate influenza therapeutics. © 2011 Huang et al.

Banner D.,Toronto General Research Institute | Kelvin A.A.,Immune Diagnostics and Research
Journal of Infection in Developing Countries | Year: 2012

Highly pathogenic avian influenza H5N1 is a threat to global public health as a natural pandemic causing agent but has recently been considered a bioterrorism concern. The evolving view of the H5N1 virus necessitates the re-evaluation of the current status of H5N1 therapeutics and prophylactics, in particular the preparation of viable H5N1 vaccination strategies as well as the use of ferrets in influenza research. Here the highly pathogenic H5N1 virus dilemma is discussed in context with the current H5N1 vaccine status and the use of the ferret model. Previously, the development of various H5N1 vaccine platforms have been attempted, many of them tested in the ferret model, including vector vaccines, adjuvant vaccines, DNA vaccines, and reverse engineered vaccines. Moreover, as ferrets are a superlative animal model for influenza investigation and vaccine testing, it is imperative that this model is recognized for its uses in prophylactic development and not only as an agent for creating transmissible influenza viruses. Elucidating the ferret immune response and creating ferret immune reagents remain important goals in conjunction with the development and manufacture of H5N1 vaccines. In summary, an efficacious H5N1 vaccine is urgently needed and the ferret model remains an appropriate model for its development. © 2012 Banner and Kelvin.

Loading Immune Diagnostics and Research collaborators
Loading Immune Diagnostics and Research collaborators