Biology

In summary, our biology projects are:

   
Molecular diagnostics of respiratory viruses
 
In order to improve the diagnostics of respiratory infections, we developed a highly multiplexed molecular diagnostic assay targeting 24 respiratory virus species and types. This assay is automated and requires little hands on time, thus is appropriate for use in a clinical laboratory. It has been used to test over 1000 specimens from children under 3 years of age, from HIV patients and from COPD (Chronic obstructive pulmonary disease) patients.

Student: Frédéric Raymond
Collaborators: Guy Boivin & Gaston De Serres
Paper: Journal of Clinical Microbiology (2009) doi:10.1128/JCM.01297-08
Posters: pdf:Raymond_2007.pdf; pdf:Raymond_2007_2.pdf; pdf:Raymond_2008.pdf

S-OIV diagnostic and characterization using laboratory rapid multiplexed system
 
 
In order to further develop a highly multiplexed system of detection and characterization of the pandemic swine originating influenza virus (S-OIV) type A H1N1, suitable recombinant proteins of the peplomers hemagglutinin (H1) and neuraminidase (N1) are being developed. Polyclonal and monoclonal antibodies of different specificities are also being developed to support a highly multiplex automatic diagnostic system. In a different application scope, the same system is also being tested for other immunological tests using MoAbs such as; high-throughput screening during the cloning of Ab-secreting cells and/or MoAb competitition assays.

Student: Miguel Retamal

 
ChIP on chip experiment on treated IFNa2 human macrophages inoculated or not with HIV. Finding potential anti-HIV interferon–stimulated genes (ISGs)
 
 
Chromatin Immunoprecipitation (ChIP) is a powerful tool for studying protein/DNA interactions. ChIP enables the identification of individual, or multiple DNA-binding targets for gene-regulatory proteins, such as transcription factors, using the specificity of immunoprecipitation and the sensitivity of polymerase chain reaction (PCR). Since it is already known that IRF-7 is the master regulator of type I interferon (IFN) dependent immune response, we decided to focus on this factor for immunoprecipitation experiment on human +/- IFN treated macrophages inoculated or not with HIV. We have observed with our present promoter array (19,000 features) and began to analyse the induction of a number of interesting candidate genes. We utilised quantitative real-time PCR (qRT-PCR) for validation and further investigation. We will test directly the cooperative nature and selection of certain ISGs as well as possible interactions with HIV regulatory and structural proteins on our new biomolecular interaction apparatus. The technology of the Silicon Kinetics Biosensor will allow the monitoring of interactions between any biomolecules including proteins, DNA and RNA.

Person: Lynda Robitaille

 
Global gene regulation during HIV-1 infection: The role of interferon-induced gene products
 
 
Our research aims primarily to decipher the interferon pathway and its role during HIV infection. We performed a genomic screen for inhibitors of HIV replication focusing on interferon-stimulated genes (ISGs). We hypothesized that certain ISGs inhibit either directly or indirectly HIV replication in monocyte-derived macrophages (MDMs). We selected preferentially transcription factors that can be further investigated by a chromatin immunoprecipitation on chip approach since ISGs act in concert and a chromatin-IP approach will enable the characterization of additional partners of the IFN response complexes.

Student: Mélissa Sirois
Poster: pdf:Sirois.pdf

 
R5 and X4 HIV Viruses Differentially Modulate Host Gene Expression in Resting CD4+ T Cells
 
 
Temporal mapping of global gene expression in naive and memory human CD4+ T cells after infection with relevant prototypical X4 and R5 viruses was performed using oligonucleotide arrays. The temporal resolution provided a comprehensive data set and allowed all significant differences between the transcriptomes of viral coreceptor usage to be revealed.

Student: Mélissa Sirois
Poster: pdf:Sirois_2006.pdf
Paper: AIDS Research and Human Retroviruses (2008) doi:10.1089/aid.2007.0120