LSI researchers draw more than $8M in CIHR Spring 2022 Project Grants

July 18, 2022

Congratulations to the successful applicants in the CIHR Spring 2022 Project Grant competition!

Listed below are the PIs on the ten funded projects. LSI Director Dr. Josef Penninger and Deputy Director Dr. James Johnson described the results as a remarkable success: 42% of the LSI applications were approved, whereas the Canadian national and UBC averages are 19% and 22%, respectively.

“This is a great testament to our thriving research community and the great work that is done at all levels,” they said, “from grant development support by Richa Anand and Nina Maeshima to the technology core support to – of course – all the great research work and ideas that are the key and foundation to this success.”

Mark Cembrowski
A specialized neural circuit representing novelty on behavioural timescales
Recognizing and responding to novelty is critical for everyday life, and many neural disorders exhibit novelty-related behavioural manifestations. As such, understanding how novelty stimuli are coded in the brain is important for both fundamental and clinical neuroscience. Our preliminary data has uncovered a rare, atypical neuron type in the hippocampus that seems uniquely poised – at molecular, cellular, circuit, and behavioural levels – to produce sustained cellular “memory” of transiently encountered novel stimuli. Capitalizing on these preliminary findings, our laboratory will combine cutting-edge high-throughput technologies and big data analysis in mice to uncover how novelty is coded and stored in the brain. To do so, we will begin by using brain slice preparations, and examine whether these atypical neurons have specialized properties that can amplify and transmit slow signals associated with novel stimuli. To complement these experiments, we will perform cellular imaging during behaviour, and manipulate atypical neurons and their molecules to identify neural mechanisms that drive novelty-associated behaviour. Finally, measuring the expression of every gene in the genome for individual cells, we will establish a neural “blueprint” of the molecules and cells that receive signals from these atypical neurons. We will then study these downstream neurons to understand how distinct layers of processing in the brain acts to transform and transmit novelty-related signals. Our research here provides multidisciplinary insight into the brain’s map of novelty and familiarity, integrated across molecular, cellular, circuit, and behavioural neuroscience. This will provide a comprehensive understanding of the basic biology of novelty recognition and response. In the long term, such results will generate a framework by which recognition and novelty-associated impairments can be understood and potentially treated.

 

Dr. Ethan Greenblatt
Ethan Greenblatt
Determining the role of FMRP complexes in autism-relevant gene expression
Mutations in the gene FMR1 lead to disorders that are associated with intellectual and reproductive impairment. This includes fragile X syndrome, which is the most common cause of autism. The FMR1 gene encodes a protein FMRP which regulates the translation (protein production) of other genes in the brain and reproductive tissues. When mutated, this regulation is disturbed, and many autism-relevant genes become expressed at lower levels than normal. The loss of FMRP leads to severe intellectual disability, as well as impaired sperm and egg development. Despite considerable effort, little is known about how FMRP promotes the translation of its targets. We have developed a new system for discovering the details of this process taking advantage of the accessibility of the oocytes of the model organism Drosophila melanogaster. We have used this system to identify for the first time partner proteins that work with FMRP to promote autism-relevant gene expression. This proposal aims to understand how these proteins work with FMRP to promote autism-relevant gene expression, with the goal of opening up new avenues for the development of treatments for autism patients.

 

Hongshen Ma
Behaviour-based cell separation to interrogate host cell heterogeneity in CAR-T cell therapies
Chimeric antigen receptor cell therapy is a new form of cancer therapy that modifies a patient’s own immune cells in order to give them the ability to eliminate cancer cells. These therapies have been shown to be highly effective against certain cancers. A major challenge in the continued development these therapies is that most of the modified immune cells do not participate in the killing of tumor cells as intended. This variability increases the potential for side-effects, as well as higher dosage requirements that results in greater cost. In order to determine why only some of the modified immune cells are functional, we are developing a technology to separate cells based on behaviour observed under a microscope. Using this technology, we will separate cells that function efficiently in tumor cell killing in order to study them in isolation to determine molecular basis that drive their function. This capability will reveal potential approaches to improve the design of these therapies to improve outcomes for patients by reducing side-effects and dosage requirements.

 

Role of MERCs and Mitophagy in Cancer Progression
The cell is surrounded by a lipid membrane and contains multiple, distinct organelles, also surrounded by membranes. Different organelles contact each other, forming nanometer (nm)-scale membrane contact sites observed by electron microscopy. Below the ~250 nm limit of visible light to distinguish between two adjacent objects (diffraction barrier), these contacts are therefore difficult to visualize by conventional fluorescence microscopy. Applying machine learning to super-resolution fluorescent microscopy, that breaks the diffraction barrier, we developed approaches to study contacts between two organelles: the endoplasmic reticulum, responsible for the synthesis of cellular proteins, and mitochondria, which generates the energy required for cellular function. Our focus is a protein called Gp78, which induces the formation of a distinct type of mitochondria-endoplasmic reticulum contact (MERC) and also induces the endoplasmic reticulum to engulf damaged mitochondria, resulting in the destruction of the engulfed mitochondria. This latter process, called mitophagy, is important as it destroys damaged mitochondria which produce oxygen radicals harmful to the cell. We will study how Gp78 regulation of MERCs and mitophagy may prevent progression of a cancer to malignancy. We will use our novel super-resolution imaging analysis approach to identify the contacts where Gp78, and other proteins, mediate physical interaction between endoplasmic reticulum and mitochondria. We will also test how loss of these proteins and contacts impacts mitochondrial health and behavior and extend these studies to cells in tumors to determine how these mechanisms affect tumor cell production of harmful oxygen radicals. We will define the mechanisms by which Gp78 induces MERCs and mitophagy and test whether targeting these mechanisms impacts tumor cell production of oxygen radicals.

 

Understanding sex differences in the neuronal control of whole-body fat storage and breakdown
In humans, storing too much body fat leads to a higher risk of developing heart disease and type 2 diabetes. For a long time, researchers have known that men and women store fat differently in their bodies, and also have a different risk of developing heart disease and type 2 diabetes. Unfortunately, most studies aimed at figuring out ways of correcting excess body fat to prevent heart disease and type 2 diabetes do not include both men and women. This is a problem because drugs used by doctors to fix excess fat storage do not work equally well in both men and women. To develop better treatments for people with too much body fat, researchers will need to learn more about how men and women store fat differently. My lab uses the fruit fly to make basic discoveries about fat storage. Scientists have shown that the same factors control body fat in flies and humans. Also, male and female flies store fat differently, just like in humans. These similarities mean that studying flies is a great way to learn more about how males and females store fat differently. Our research in flies shows that males and females store fat differently mostly because of one cell type in the brain called a neuron. Specifically, we found that different genes act in neurons in males and females to control body fat. This means the genes that act in neurons to control body fat are not shared between males and females. Our project goal is to identify genes that act in male and female neurons, respectively, to control body fat. Then, we will carry out tests to find out how these genes change neuron function, how the changes to body fat come about (ex. shifts in eating or movement). By providing reliable information about which genes act in neurons to control body fat in males, and which genes do the same job in females, researchers will have important clues to choose good targets for new drugs aimed at treating heart disease and type 2 diabetes in men and women, respectively.

 

Mechanisms of endogenous retrovirus-mediated antiviral immunity against genital herpes simplex virus 2 infection and disease.
Herpes simplex virus 2 (HSV-2) is a sexually transmitted virus that affects over 500 million individuals worldwide. HSV-2 establishes a life-long infection with the host and causes lesions, pain, and discomfort in the female genital tract that persists for life. In addition, HSV-2 infection increases the risk of co-infection by HIV or hepatitis C virus as well as pathogenic bacteria that are responsible for bacterial vaginosis. Although the antiviral drug, acyclovir, is available, acyclovir needs to be taken as a daily five dose regimen for the duration of symptoms and does not prevent recurring symptoms. There are currently no vaccines available to treat HSV-2, in part due to inherent challenges associated with the development of mucosal vaccines. The goal of our project is to identify novel host mechanisms that boost antiviral responses against genital HSV-2 infection that will ameliorate the disease caused by this virus. My group recently found that viral sequences that are present in the genome of most eukaryotes called endogenous retroviruses (ERVs) are involved in the protection against genital HSV-2 infection in mice. Our project will build on this finding and will investigate the molecular interactions between ERVs and vaginal cells that mediates protection against genital HSV-2 infection and disease. We will achieve this using mouse models and human cells in combination with virology, immunology and bioinformatic techniques. This will allow us to identify new molecules that are involved in the protection against HSV-2 infection and disease that can further be targeted to boost antiviral responses in the female genital tract. Ultimately, our work will aid in the development of new host-directed antiviral therapies.

 

Filip van Petegem
Structural and functional investigation of Junctophilins in health and disease
The cells in our cardiac and skeletal muscle are highly specialized, displaying distinct shapes. These shapes are absolutely required for normal function, and are determined by the various proteins that are expressed in these cells. Cells are surrounded by membranes that keep the content inside separate from the outside. But inside the cells are different compartments that are also surrounded by their own membrane. A very peculiar property of muscle cells is that there are ‘contact’ sites where different membranes meet. These contacts are critical: without them, the muscle cells would not be to process the signals that lead to contraction. This proposal focuses on Junctophilin, a very peculiar protein that has the capacity to bring different membranes together. In the heart, mutations that affect the gene encoding for Junctophilin can lead to serious problems. In particular, they cause hypertrophic cardiomyopathy, a condition that leads to a weakened heart and the potential for life-threatening disturbances in heart rhythm. We will figure out how Junctophilin works by studying its 3D structure, and how it binds the different proteins in muscle cells. We will also study the effect of mutations that cause cardiomyopathy: by comparing the 3D structure of ‘normal’, healthy Junctophilin with the structure of ‘diseased’ Junctophilin, we expect to gain fundamental insights into the disease mechanisms. We expect this research to give clues for new therapeutic approaches.

 

Regulatory mechanisms of voltage-gated calcium channels
Many cells in our bodies rely on electrical signals. This includes neurons, but also heart muscle and skeletal muscle cells. These cells are surrounded by a membrane, which forms a physical barrier for many molecules. Embedded within these membrane are specialized proteins that are responsible for the electrical signals. Also known as “ion channels”, these proteins form gateways for various ions to move into our out of the cell. As these ions carry electrical charge, this movement is what shapes the electrical signals. Because these electrical signals affect the ability of our brains to compute information, and the ability of our hearts to beat in a rhythmic fashion, it is paramount that they are regulated properly. Any small deviation in their regulation can cause devastating and life-threatening conditions, such as heart rhythm disorders. In this proposal, we aim to understand how these ion channels are regulated by calcium ions. Curiously, these calcium ions first enter the cells through the ion channels, and then provide a signal to these channels to ‘shut down’. How exactly this process happens is currently not known. We will tackle this problem by using very advanced imaging methods. As proteins like ion channels are too small to be observed via regular microscopes, we instead rely on electron microscopy. We collect hundreds of thousands of images of these channels, which are then superposed onto one another to enhance the contrast. By collecting images from different view angles, we can then determine the 3D structure of the protein. This methodology has advanced considerably in the last few years, and can give near-atomic level resolution of the protein. In doing so, we will analyze the effect of calcium ions on the structure. We will also investigate how genetic mutations, linked to heart rhythm disorders, change the structure of these ion channels. This will give much-needed fundamental insights into the origins of cardiac arrhyhtmia.

 

François Jean
Pre-clinical development of broad-spectrum antiviral strategies against human respiratory viruses of pandemic concern
Respiratory viruses such as SARS-CoV-2 (the virus causing COVID-19) and Influenza A virus, have inarguably had an enormous impact on human health. Although vaccines have greatly limited COVID-19 and Influenza-related hospitalizations and deaths, these viruses are continually changing, resulting in decreased effectiveness of vaccines over time. Drugs that can prevent and treat infections caused by respiratory viruses are therefore also needed. Our research teams have discovered an exciting drug that can block infections caused by multiple viruses, which we call “broadly acting antivirals”. The drug, N-0385 blocks a human protease (a protein that cuts other proteins) that viruses, such as SARS-CoV-2 and Influenza A virus, take advantage of to enter the cells in our respiratory tract. In this research proposal, our aims are to further improve the pharmaceutical properties of N-0385 lead drugs, so they are more stable, easier to deliver and more suitable for animal and human drug trials. We will then measure how well these improved drugs can block SARS-CoV-2 and Influenza A virus infection in lung and other respiratory cell models when given alone or when combined. Overall, we anticipate that this research will advance these compounds so they can be further tested in clinical trials and in the future will lead to new and exciting therapeutic avenues for treatment of viruses with human pandemic potential.

 

Pieter CullisDr. Pieter Cullis

Development of LNP/mRNA systems for direct transfection and generation of functional Chimeric Antigen Receptor (CAR) T-cells in-vivo for treatment of blood and other cancer cell types

Chimeric Antigen Receptor (CAR) T cell therapy is relatively new and exciting form of cancer therapy which uses a patients own re-programmed immune cells to specifically target and destroy cancer cells. In this treatment, T cells (a type of immune cell) are harvested from a patients blood and re-programmed in a laboratory to express a protein called a Chimeric Antigen Receptor, which enables them to recognize and destroy specific types of cancer cells. These CAR T cells are then re-infused into the patient where they attack and destroy the cancer cells, which can result in disease remission. Several treatments have been approved by the FDA to date. The current methods of generating CAR T cells in the lab involve genetic manipulation using viruses, and the engineered cells are not the same as natural T cells, which can cause significant problems in patient treatment; further, harvesting the T cells from blood is expensive and arduous for the patient. Here, we propose to deliver the instructions for T cells to make a CAR directly in the body by using lipid-nanoparticle(LNP)/CAR-mRNA complexes, similar to the current COVID-19 mRNA vaccines. By optimizing the composition of these LNP/mRNA complexes, it is possible to enable mRNA delivery to specific tissue and cell types. The objective of these studies is to develop a method for delivery of CAR mRNA directly to T cells via lipid-nanoparticle based delivery, potentially removing significant treatment barriers to patients.