MRM-MI4 Collaborative Seed Fund Grant

Our therapeutic arsenal against bacterial infections is rapidly shrinking, as drug resistance spreads and the antibiotic development pipeline runs dry. Novel technologies that can minimize the transmission of potential pathogens, particularly drug resistant bacteria, can be part of the solution to these shortcomings. One such class of technology was recently identified by studying the anti-bacterial properties of dragonfly and cicada wings, which contain beautifully-formed and intricate nanoscale “beds of nails” that kill by physical contact rather than by the use of antimicrobial molecules. Subsequent studies suggest that certain high aspect ratio nanomaterials, termed “mechano-bactericidal” nanostructures, can mimic this behaviour and impart critical microbial damage via their nanoscale shape, while leaving mammalian cells unharmed. As with any research field in its infancy, there exists significant debate and contradictions regarding underlying mechanisms and, by extension, the optimal design strategy to maximize antibacterial performance of these nanostructures. This research will investigate antibacterial interactions between bacterial cells and nanopillars synthesized on various materials. A comprehensive understanding of cell-surface interactions will improve insights for future designs of antibacterial surfaces. As antibacterial surfaces that do not rely primarily on diffusion of antibacterial agents, mechano-bactericidal nanotopographies offer opportunities for next-generation sustainable antimicrobial materials.

The Public Health Agency of Canada anticipates increased burden of disease (i.e. Lyme disease) as a result of thermal stress and more frequent extreme weather events. Lyme disease is a severe infectious illness caused by the bacterium Borrelia burgdorferi and transmitted by tick vectors (Ixodes scapularis). There is no vaccine against Lyme disease whereas approximately 20 % of people who are treated with the recommended antibiotics will develop chronic disabling disease symptoms from fatigue, joint and muscle aches to cognitive dysfunction. Both the range of ticks and Lyme disease have been rapidly expanding in Canada, which has led to the establishment of a national medical surveillance program and prompted investigations in Lyme disease as research priority. Furthermore, ticks are responsible for the transmission of other pathogens of relevance to health, including fungi, protozoan and bacterial species. Whereas climate change is a known determinant for the expansion of this disease, little is known about the genetic and molecular mechanisms acting on the vector that underlie the increased risk of disease. This proposal will leverage on novel genomic technologies and an international team of experts in genomics, vector biology, bacteria evolution and diagnostics to address the challenge of Lyme disease. We will examine the extent of vector genomic variation in two endemic areas, namely Vermont and Québec Eastern Townships and how this relates to the rate of Borrelia infection. We will define the full spectrum of pathogenic and symbiotic microbial communities (the microbiome) colonizing the vector, and investigate the impact of vector genomic variation on the composition of these communities. In turn, we will address whether the vector microbiome influences the risk of vector infection and pathogen transmission. These studies will lead not only to a better understanding of the relation between the vector, the pathogen that it transmits and its microbiome in disease emergence but also to the identification of new molecular markers for improved disease surveillance and diagnostic. Moreover, by bringing together investigators in areas of disease activity, this research will enhance capacity for intervention against the increased threat of tick-borne infections in North America.

Tuberculosis (TB) affects more than 10 million people each year and kills more than 1.7 million people annually. Pollution is the largest environmental cause of disease and premature death in the world today, with particulate air pollution alone contributing to more than 4 million premature deaths annually. India is the epicenter of the global TB epidemic, accounting for 25% of estimated deaths. Adding insult to injury, India also has some of the worst air quality in the world which adds an additional burden to patients already struggling with a crippling respiratory illness. Due to paucity of evidence, the TB field has yet to acknowledge outdoor air pollution as an important risk factor. In this pilot study, we will first use personal aerosol monitors to characterize personal exposures to fine particulate air pollution (PM2.5) among 100 active TB patients in New Delhi as well as in Udupi town, Karnataka, to contrast exposures experienced by TB patients in a high polluted versus less polluted area of India. As a second objective, we will develop a new model to predict neighbourhood-level air pollution concentrations based on street-level and satellite imagery. This model will be developed using modern “deep learning” methods applied to large databases of paired image-exposure information collected across our research locations. The final model will serve as a cost-effective resource to estimate environmental exposures for large numbers of study participants in our subsequent follow-up studies outlined in future grant applications (section 4). In summary, TB and air pollution both contribute substantially to the overall global burden of disease, but the combined impact of these risk factors has been largely overlooked. We aim to change this through a new interdisciplinary research collaboration (with an early career investigator in lead), starting with a seed grant that will enable the development of a state-of-the-art model that will allow us to scale exposure estimation to future, larger, cohort study on how pollution affects TB outcomes.

The World Health Organization advocates for increased accessibility of point-of-care (POC) diagnostics for HIV-1 and related infections (including hepatitis C virus (HCV)) in hard-to-reach settings that lack laboratory infrastructure. Drs. Trifiro, Kirk and Paliouras have re-designed PCR technology towards the development of a true POC, rapid, portable and battery-powered device, to provide “label-free” quantitative detection of microbial infections. In this proposal, we intend to develop an integrated “sample-to-result” diagnostic test for the detection and quantification of HIV and HCV using the patent-approved and proprietary Plasmonic PCR platform. The performance of Plasmonic PCR will be compared to government-standard qPCR viral load detection assays. The Plasmonic PCR device will be evaluated in key vulnerable provincial populations, including the MUHC cohort of new migrants, refugees and asylum seekers, the Canadian Co-Infection Cohort of HIV/HCV co-infected persons, and the Primary HIV cohort of men who have sex with men and people who inject drugs. With the success of this study, we intend to apply the technology to other viral and microbial infections, (e.g. human papilloma virus and tuberculosis) as part of a multi-disease/multiplex mobile rapid POC testing strategy.

Human respiratory syncytial virus (RSV) is an important cause of lower respiratory tract disease. It infects the respiratory tract of most children before the age of 2 and it is the greatest cause of infant hospitalisation worldwide. For most children and infants, it causes symptoms that are no more serious than a cold. However, in some cases, children develop bronchiolitis, which requires hospitalization, and can be life threatening. At this time, it is not clear what immune responses are best able to control this virus so there is no vaccine and no drugs that can treat RSV infections once they have started. However, antibodies (Abs) are an interesting candidate. A commercially available monoclonal Ab (mAb) called pavilizumab is in use; however, it can only be used preventatively to protect high risk children from infection with RSV. Abs have two main functional domains, the Fab domain recognizes a part of a pathogen or virus (antigen) and the second, termed the Fc domain, allows Abs to interact with a wide range of immune cells, that once activated, can exert antiviral functions. We have developed a platform of tests that measure these Fc-dependent antiviral activities. To make these tests specific for RSV we require a source of Ab that recognizes RSV and a target cell that expresses the RSV antigens expressed on infected cells. In this proposal, we will engineer RSV antigen positive target cells and acquire biological fluid samples from nasopharyngeal swabs that are used to diagnose RSV infection in children. After quantifying the amount of Ab in these samples, we will examine the function of the RSV-specific Abs in the biological fluid of samples from infected children. This information will be compared to the preventative Ab, pavilizumab. The project will ascertain how Abs to RSV that develop in children with respiratory illness severe enough to require hospitalization differ from pavilizumab. The project will generate information that can be used to select effective therapeutic Abs and assess the effectiveness of novel vaccines that are being designed to protect against RSV infection.

Despite more than 100 years since the discovery of Mycobacterium tuberculosis (Mtb), this organism remains one of the most successful human pathogens. Approximately 2 million people die of TB annually and 8 to 10 million new cases of active tuberculosis occur each year. Millions of individuals worldwide are treated with anti-tuberculosis therapy (ATT) to control active disease or prevent recrudescence of latent Mycobacterium tuberculosis (Mtb) infection. Although these antibiotics are effective at decreasing TB-associated mortality, they do not lead to a sterilizing cure and, paradoxically, may leave individuals more susceptible to reinfection. Furthermore, these antibiotics may have previously unrecognized consequences on the commensal microbiota that perform important roles in host defense. The central hypothesis of the current proposal is that anti-TB antibiotics compromise microbiota-immune crosstalk that prevents the generation of permanent immunity to Mtb. Our work will define the intersection between the microbiome and the immune response to Mtb infection and have rapid clinical impact for this devastating disease.

Accurate, robust and rapid surveillance of water-borne parasites has significant impact on public health especially among vulnerable populations. The impact of these debilitating diseases caused by parasites are enormous, affecting over a million people across North America annually. The slow turnaround time for traditional identification techniques and labor-intensive methods such as microscopy is a driving factor to develop new assays and methods for rapid and accurate identification at the point of need.

We aim to develop an ultrasensitive electrical apta-nano assay for rapid identification of water-borne parasites such as Cyclospora, Cryptosporidium and Giardia. The proposed assay is based on a novel hierarchical gold/graphene nanostructured platform that provides an ultra-sensitive, specific and label-free electrical readout upon capture of target parasites on the surface-immobilized aptamer. We utilize this nanostructured platform and the aptamer recognition element in conjunction with parallel nano/microfluidic sample delivery for efficient delivery of the sample solution and buffers in a multiplex manner. First, we develop a specific biorecognition element by designing aptamers specific towards Cyclospora, Cryptosporidium and Giardia. Second, we develop a sensitive electrical apta-nano readout by fabricating hierarchical 3D gold/graphene nanostructures and study the surface functionalization with aptamer, and test its unique label-free electrical behavior in the presence of Cyclospora, Cryptosporidium and Giardia. Third, we develop on-chip multiplexity from unprocessed samples by fabricating parallel fluidic channels with micro/nanofilter connected to the electrical apta-nano readout and validate its performance with Cyclospora, Cryptosporidium and Giardia from environmental samples and specimens from patients. In close collaboration with MUHC medical microbiology laboratory, we compare the performance of prototype with the samples and data submitted for the parasites panel.

Tackling an unmet clinical need: Cancer is a devastating diagnosis for patients, but even more so for young mothers diagnosed with postpartum breast cancer (PPBC), which tends to be metastatic. The latter means that mothers must put caring for their newborns on hold, while they undergo surgery, post-operative recovery, and additional aggressive chemotherapy, as PPBC cases are often considered high risk for recurrence. The physical, and psychological burden does not affect only the woman diagnosed with breast cancer, but also her entire family. Clearly, more research needs to be focused on this subtype of breast cancer.

A major goal of the del Rincon lab has been to accelerate therapeutic discoveries for women diagnosed with PPBC and develop novel therapies for this metastatic disease. Our clinical data show that women diagnosed with PPBC are at increased risk for liver metastasis relative to nulliparous women. The Brodt lab has extensive experience in the study of the biology of liver metastasis. Here the Brodt and del Rincon labs have teamed up to elucidate the mechanism(s) underlying the increased propensity of PPBC for liver metastasis. We postulate that the MNK1/2 axis plays a role in this predilection and will use MNK1/2 inhibitors to inhibit liver metatsasis in a pre-clinical model of PPBC. Moreover, we propose to use MNK1/2 inhibitors in combination with immunotherapy in an effort to potentiate an immune attack on metastatic PPBC. MNK1/2 have entered clinical trials, thus we are confident that the discoveries made by our team could have important translational applications in the foreseeable future. Scientists, Clinicians and Advocates team up to fight postpartum breast cancer metastasis: We are fortunate to have the full support of a network of scientists, clinicians, and patient advocates, who are dedicated to ensuring the successful completion of the proposed, and future, work. Funding will be invaluable to help Dr. del Rincon’s career development as an independent breast cancer researcher.

Sepsis is a leading cause of death in the intensive care units and is responsible for ten thousand deaths in Canada each year. Skeletal muscle dysfunction manifested as fiber atrophy and weakness is a primary clinical observation in critically ill septic patients. Long-term ramifications of limb muscle weakness include functional impairment and poor quality of life. Sepsis-induced skeletal muscle atrophy and weakness are associated with accumulation of damaged and dysfunctional mitochondria (the main source of cellular energy). In normal skeletal muscles, dysfunctional mitochondria are selectively recycled through the autophagy pathway, a process known as mitophagy. In this process, autophagosomes recognize dysfunctional mitochondria primarily through the PINK1-Parkin pathway. This process is inhibited by a protein called P53 which retains Parkin in the cytosol. The main aim of this proposal is to evaluate the therapeutic potentials of enhancing mitophagy by overexpressing Parkin and PINK1 selectively in skeletal muscles or by inhibiting p53 on mitochondrial function, atrophy and depressed contractility in a mouse model of sepsis that simulates human sepsis. To achieve this aim, we have assembled an experienced team of leading investigators in the fields of skeletal muscle biology and mitochondrial structure and function, Hussain, and McBride, who have extensive expertise in skeletal muscle diseases, and mitochondrial function. Overexpression of Parkin and PINK1 will be achieved by injection of adeno-associated viruses in limb muscles and these muscles will be examined under control and septic conditions. P53 inhibition will be achieved by using mice defective in muscle p53 or by using a pharmacological p53 inhibitor. Mitochondrial function and morphology as well as muscle fiber size and contractile performance will be evaluated in both control and septic mice. We are certain that when the project is completed the knowledge that will emerge will be foundational to the development of novel strategies that rely on PINK-1-Parkin pathway activation in septic skeletal muscles. This activation could result in the prevention, possibly even the reversal, of muscle dysfunction in septic patients. The project, therefore, represents research that has rich translational potential for improved care of critically ill patients.

Despite the significant progress in our understanding of the multiple targets associated with the complex signaling networks that characterize drug resistance in the advanced stages of cancer, our approaches to drug discovery have widely favored the « one-drug, one-gene » strategy. According to this assumption, the selectivity of a drug for its cognate target is directly related to its anti-tumour activity. Paradoxically, nearly two decades of work with this hypothesis, have shown that many clinically successful modulators designed to be target-specific were classified as “multi-targeted drugs” a posterori and these exhibited potent activity in the clinic. Analysis of 974 anticancer agents from 1995 to 2007, in developmental phases (phase I to registration) led to an overall attrition rate as high as 82%. However, this rate fell to only 52% when the analysis was restricted to a subset of multi-targeted drugs. There thus needs to be a paradigm shift in our approach to anti-cancer drug discovery. The complexity of the signaling networks that drive tumour progression imposes a rather one-two, or three-punch approach. In this context, we developed a novel approach termed « combi-targeting » that addresses the genetic complexity and the target heterogeneity of solid tumours in the advance stages. The combi-targeting concept is a McGill-developed drug discovery strategy that seeks to design single molecules termed “combi-molecules to block the adverse effects of the mumours in multiple fronts. One of the major problem with tumour cells is that they can hide from the immune system. Here we are using our double-sword approach to force them to express protein that will render them visible by the immunize system and at the same time we program them to open the eye of the immune system so that it can see them and destroy them. This is a strategy that has never been tried before in drug design against cancer.

Parkinson's disease (PD) is a common neurodegenerative disease that affects 1-2 per 1000 of the general population. However, PD prevalence is increasing with age and PD affects a striking 1% of the population above 60 years. The etiology of PD is unknown but strong experimental and epidemiological data supports PD as an inflammatory disease that originates from the gut.

Based on findings from human populations and experiments in mouse model systems, we propose that the cause of inflammatory dysregulation in PD patients is infection with common pathogens that alter the gut mucosal immune balance. In support of this hypothesis, we and others have shown that the same inherited genetic mutations are shared between inflammatory bowel disease (IBD), leprosy reactions (characterized by systemic dysregulated inflammation leading to nerve damage), and PD. Moreover, we have shown that mice engineered to carry a known PD susceptibility gene will develop PD-like neurological and clinical symptoms following infection with a gut pathogen. The pathological symptoms in these mice only develop after the initial gut infection has been cleared. This is a stunning parallel to leprosy reactions that manifest in a majority of patients only after microbiological cure of the M. leprae pathogen.

In the present application, we will expand on the role of infection in the etiology of PD by employing cellular and animal models established in our laboratories. We will conduct a survey of select pathogens for their impact on immune mechanism linked to PD and their ability to induce Parkinson-like symptoms in mice with a genetic PD-susceptibility background. These experiments will pinpoint the types of pathogens that are candidates for being causative agents of PD and lay the foundation for future pre-clinical and clinical studies of PD prevention.

The concept of treating cancer through the activation of the patient’s own immune system to kill tumor cells led to the development of immune checkpoint inhibitors (ICI). These drugs revolutionized the field of oncology as they control cancers with otherwise very poor prognosis. However, as a consequence of immune activation, up to 50% of cancer patients treated with ICI develop immune related adverse events (irAE, e.g. inflammation of the colon, lungs, joints). The severity of these irAE often requires the use of drugs to control the damage associated with excessive immune activation (immunosuppressive treatment, e.g. prednisone, monoclonal antibodies anti-inflammatory cytokines). Recent evidence suggests that some immunosuppressive treatments used to control irAE are associated with reduced patient survival. Therefore, it is urgent to define the optimal therapeutic approach to ICI-irAE minimizing its negative impact on cancer outcomes. This will be addressed by this proposal. A team of clinicians and basic scientists with unique expertise in humanized mouse cancer models will develop an unprecedented system to tackle the urgent question that most patients with an ICI-irAE have: ‘What is the optimal way to treat ICI-irAE?’.