Critical disease caused by the new 2009 pandemic influenza virus (nvH1N1) is a challenge for physicians and scientist. As evidenced in SARS and H5N1, the development of an effective immune response plays a key role to overcome viral diseases. We studied host`s gene expression signatures, cytokine and antibody responses along the first week of hospitalization in 19 critically ill patients with primary nvH1N1 pneumonia and two degrees of respiratory involvement. Presence of comorbidities and absence of immunosuppresory conditions were the common antecedents in both groups. The most severe patients (n=12) showed persistant respiratory viral secretion, increased levels of pro-inflammatory cytokines and chemokines in serum, and elevated systemic levels of two immunosuppresory cytokines (IL-10 and IL-1ra). Both groups were able to produce specific antibodies against the virus. The average day for antibody production was day 9 in the course of the disease, defining an early period of innate immunity and a late period of adaptive immunity. The most severe group evidenced a poor expression of a set of MHC class II and T cell receptor (TCR) related genes participating in antigen presentation and cell mediated immune responses in the late phase. 7 patients of this group finally died. This findings evidence that, as observed in sepsis, severe H1N1 disease course with immunoparalysis, which could explain the poor control of the virus along with the increased incidence of bacterial superinfection observed in these patients.
Host adaptive immunity deficiency in severe pandemic influenza.
Specimen part, SubjectView Samples
To further investigate the underlying mechanisms of severe acute respiratory syndrome (SARS) pathogenesis and evaluate the therapeutic efficacy of potential drugs and vaccines it is necessary to use an animal model that is highly representative of the human condition in terms of respiratory anatomy, physiology and clinical sequelae. The ferret, Mustela putorius furo, supports SARS-CoV replication and displays many of the symptoms and pathological features seen in SARS-CoV-infected humans. We have recently established a SARS-CoV infection-challenge ferret platform for use in evaluating potential therapeutics to treat SARS. The main objective of the current study was to extend our previous results and identify early host immune responses upon infection and determine immune correlates of protection upon challenge with SARS-CoV in ferrets.
Lack of innate interferon responses during SARS coronavirus infection in a vaccination and reinfection ferret model.
Specimen partView Samples
Background: Pandemic H1N1 influenza A is a newly emerging strain of human influenza that is easily transmitted between people and has spread globally to over 116 countries. Human infection leads to symptoms ranging from mild to severe with lower respiratory complications observed in a small but significant number of infected individuals. Little is currently known about host immunity and Pandemic H1N1 influenza infections.
Modeling host responses in ferrets during A/California/07/2009 influenza infection.
Specimen partView Samples
A global genomics approach was used to identify patterns of immune dysregulation during H5N1 influenza virus infection as the host response, in particular hyperchemokinemia, is thought to contribute to the extreme pathology associated with this disease.
Gene expression analysis of host innate immune responses during Lethal H5N1 infection in ferrets.
Specimen partView Samples
To further identify and understand the molecular and immunological correlates of pathology for SARS-CoV infection, we infected 129/S6/SvEv or B129 mice with the TOR2 strain of SARS-CoV. SARS-CoV was detected in the lung and nasal turbinates of infected mice peaking at 1 day post infection (DPI) in both tissues before decreasing rapidly to levels below detection at 7 DPI and 3 DPI, respectively. Pulmonary lesions in virus-infected animals included bronchiolar, peribronchiolar, and perivascular foci of mild to moderate subacute inflammation. Chronic inflammation included inflammatory macrophages, lymphocytes, and plasma cells. Neutralizing antibodies appeared on 5 DPI (IgM); converting to IgG on 7 DPI. Despite the prevailing notion that SARS-CoV interferes with the induction of interferon (IFN) signaling, mice infected with SARS-CoV in vivo demonstrated significantly increased expression of innate antiviral interferon (IFN) response genes (IRGs) in the lungs during the first week of acute infection. By the end of the second week of infection, coordinated expression of MHC class I / II and antigen presentation genes occurred in correlation with declining viral titres. Collectively, the mouse data suggests that robust IFN-driven innate immune responses and a critical shift from innate to adaptive immune responses is necessary for clearance and recovery from SARS-CoV infection.
No associated publication
Sex, Specimen part, TimeView Samples
Background: Type I interferons (IFNs) are essential to the clearance of viral diseases, in part by initiating upregulation of IFN regulated genes (IRGs). A clear distinction between genes upregulated directly by virus and genes upregulated by secondary IFN production has not been made. Here we investigated the genes regulated by IFN-a2b compared to the genes regulated by SARS-CoV infection in ferrets.
Early gene expression events in ferrets in response to SARS coronavirus infection versus direct interferon-alpha2b stimulation.
Specimen partView Samples
The 2009 H1N1 influenza pandemic has prompted a significant need for the development of efficient, single-dose, adjuvanted vaccines. Here we investigated the adjuvant potential of CpG oligodeoxynucleotide (ODN) when used with a human seasonal influenza virus vaccine in ferrets. We found that the CpG ODNadjuvanted vaccine effectively increased antibody production and activated type I interferon (IFN) responses compared to vaccine alone. Based on these findings, pegylated IFN- 2b (PEG-IFN) was also evaluated as an adjuvant in comparison to CpG ODN and complete Freunds adjuvant (CFA). Our results showed that all three vaccines with adjuvant added prevented seasonal human A/Brisbane/59/2007 (H1N1) virus replication more effectively than did vaccine alone. Gene expression profiles indicated that, as well as upregulating IFN-stimulated genes (ISGs), CpG ODN enhanced B-cell activation and increased Toll-like receptor 4 (TLR4) and IFN regulatory factor 4 (IRF4) expression, whereas PEG-IFN augmented adaptive immunity by inducing major histocompatibility complex (MHC) transcription and Ras signaling. In contrast, the use of CFA as an adjuvant induced limited ISG expression but increased the transcription of MHC, cell adhesion molecules, and B-cell activation markers. Taken together, our results better characterize the specific molecular pathways leading to adjuvant activity in different adjuvant-mediated influenza virus vaccinations.
Molecular characterization of in vivo adjuvant activity in ferrets vaccinated against influenza virus.
Specimen part, TreatmentView Samples
Pandemic H1N1 influenza A Human infection leads to symptoms ranging from mild to severe with lower respiratory complications observed in a small but significant number of infected individuals. Microarray analysis of the lymph nodes from ferrets infected with A/California/07/2009 shows intense gene upregulation during days 3 and 5 post-infection, and followed by marked downregulation during days 7 and 14 post infection. Gene expression profiles during the upregulation phase show intense chemokine activity, cell replication and activation of the lymphocyte-related signaling pathways.
Sequencing, annotation, and characterization of the influenza ferret infectome.
Specimen part, TimeView Samples
A doxycyline-inducible INS-1 insulinoma cell line expressing proinsulin (C96Y)-GFP was engineered. Addition of doxycyline causes the production of the proinsulin (C96Y)-GFP, which is retained in the endoplasmic reticulum. This study analyzes the gene expression changes that occur after doxycyline-induced expression of proinsulin (C96Y)-GFP for 24h, 48h and 5 days. Expression changes were compared between control un-induced cells and cells treated with doxycyline. Three replicates (experiments) were performed for each time point.
Endoplasmic reticulum stress response in an INS-1 pancreatic beta-cell line with inducible expression of a folding-deficient proinsulin.
Cell lineView Samples
Frequent hemodialysis is associated with improvement in myocardial mechanics and cardiac gene expression profile
Impact of frequent nocturnal hemodialysis on myocardial mechanics and cardiomyocyte gene expression.
Age, Specimen partView Samples