Microfluidic Instrumentation for Single-Cell Chemical Genetics

Healthy cell behavior, cell differentiation and disease progression are all governed by complex protein interactions and regulatory networks across different cells. Unraveling the specific, time-dependent chain of events within cells has proven challenging for several reasons. First, diversity in cell types and the cumulative effects of past cell history mean that cells may vary in their response to chemical environments. Additionally, conventional methods of cell analysis are generally restricted to averaging measurements of large populations of cells, or analyzing cell response at a single point in time. Because these ensemble measurements and snapshots obscure persistent and time-dependent behaviour, deciphering the underlying molecular mechanisms of cellular response is difficult. A deeper understanding of such pathways is essential to the advancement of fundamental biological research, to the diagnoses of disease, and to the development of medical interventions. New technologies are needed to enable continuous monitoring of large numbers of single cells, subject to precisely-controlled sequences of chemical stimuli. Recent developments in micro-fabrication technology has led to micro-scale cell culture “chips”, with features similar to electronic micro circuits. Thousands of microscopic channels and valves can be tightly integrated into powerful biomedical sample processing devices the size of an iPod. Dr. Carl Hansen will focus on maximizing these state-of-the-art systems to develop new instrumentation capable of rapidly analyzing thousands of isolated single cells exposed to precisely defined and time-varying chemical conditions and drugs. Experimentation at the single cell level will accelerate fundamental biomedical research and will ultimately improve both our understanding of, and our ability to treat, disease. The ability to precisely manipulate and interrogate single cells will find broad application in health research fields including cancer biology, regenerative medicine, and drug development.

The British Columbia Adolescent Substance Use Survey

The use of tobacco, alcohol and marijuana by teenagers continues to pose a significant threat to the health of many young Canadians. Recent national surveys indicate that 18 per cent of Canadian teens smoke tobacco daily or occasionally and one-third of all teens have tried marijuana more than once, with about eight per cent of teens using it at least once a week. Just over 44 per cent of teens reported drinking one to three times each month, with an additional 17 per cent of teens aged 15 to 17 drinking one to three times a week or more. Despite extensive prevention efforts, the use of these substances appears to have become a somewhat normalized part of adolescence. The goal of Dr. Richardson’s program of research is to improve our understanding of why adolescents are using these substances, and in so doing, facilitate the development of more effective interventions. For example, Dr. Richardson will be using an internet-based web survey to collect information every six months from a large group of adolescents to examine how the influence of known risk factors for substance use, such as peer influences and psychological characteristics related to risk taking, change as the students’ progress through high school. Dr. Richardson hopes this research will enable researchers to identify specific longitudinal patterns (i.e., trajectories) of alcohol, tobacco and marijuana use and examine how the influence of known risk factors change as adolescents progress through the secondary school system. In addition to improving our understanding of the different patterns of substance use, this research will contribute to the development of individually tailored prevention and harm reduction interventions that can be delivered over the internet.

Nervous System Regeneration and Repair: Lessons From the Olfactory System

The brain or central nervous system (CNS) is especially vulnerable to permanent injury and loss of function following stroke, trauma and seizure or the onset of genetic disorders such as Huntington or Parkinson disease costing billions of dollars in health care every year and long-term loss of productivity. Despite major advances in understanding of neural development in recent years, a major challenge facing neuroscientists today is how to use this knowledge to help direct repair and rebuild the CNS after it becomes damaged. Dr. Jane Roskams uses the mouse olfactory system (nose) to study CNS repair because cells in the system have a remarkable ability to remodel, repair and regenerate, compared to other regions of the CNS. Olfactory system repair is driven by two types of cells — one that replaces lost neurons (specialized olfactory stem cells) and another that guides these replacement cells to their target (olfactory glial cells). As part of the only team in the world focused on these complementary research areas, Dr. Roskams has developed a series of tools and approaches to determine which specific cells are activated to replace damaged neurons, and to test the signals that drive this activity. She is also working to determine the unique ways that these cells contribute to repair following spinal cord injury and stroke. While transplanting either of these types of cells into injured or damaged CNS tissue could help with repair. Dr. Roskams’ work is focused on understanding how repair mechanisms work at the molecular level, with the goal of discovering if there are ways that injured cells might be manipulated into repairing themselves — a potential new way of addressing or preventing long-term CNS damage.

Improving youth sexual health in British Columbia

In spite of prevention programs that target risky sexual behaviours in youth, many BC teens continue to experience serious health and social problems related to sexually transmitted infections (STIs) and unplanned pregnancies. While untreated STIs can lead to pelvic inflammatory disease, infertility and increased risk of HIV, early maternal age can result in decreased future educational and employment opportunities for young mothers. As a Scholar, Dr. Jean Shoveller investigated the factors that play a role in the increased incidence of teen pregnancy and STIs among rural and remote BC communities. Now, Dr. Shoveller is working to reduce gaps in public health interventions related to youth sexual health by focusing on policy and program intervention research related to the health and social impacts of STIs and unwanted pregnancies amongst youth. Dr. Shoveller’s research will integrate participatory approaches to research (where youth are directly involved in the planning and implementation of research projects) with an analytical framework that examines how features of youth’s social contexts (e.g., gender, place, culture) affect youth’s sexual lives. Also, data that illustrate how context affects young people’s sexual health will be mapped to reveal how strengths and weaknesses in the health, education and social service systems affect youth’s sexual health. This research will provide researchers with new tools that can be used in new and unique participatory research opportunities that actively involve youth in research into this complex and sensitive topic and will provide public health policy makers and program planners with information to help inform decisions regarding improving and promoting youth sexual health.

The affects of Mgat5 modified glycoproteins and galectin-3 on the expression, phosphorylation and function of connexins

Cells in the human body are not isolated entities; in fact, they engage in a considerable amount of ‘cross talk’ with other nearby cells. In the most direct form of communication, protein channels pass through the membranes around neighboring cell, allowing small molecules to pass back and forth. These channels, called “gap junctions”, are made up of proteins called “connexins.” Of interest to researchers is the discovery that production of connexins is reduced in aggressive cancers compared to the surrounding tissue. It is due to observations such as this which has led scientists to believe that connexins do more than just form “tunnels” between cells. Stephen Bond is examining the link between connexin 43, the most common form of connexin, and an enzyme called Mgat5. Too much Mgat5 encourages tumour growth, and “knocking out” this enzyme (making it inoperative) increases the amount of connexin 43 protein made. Bond wants to determine whether an increase in Mgat5 increases tumour growth by decreasing connexin 43, and if so, determine how this occurs. This research could identify yet another way in which cells become cancerous, thus increasing our understanding of this class of disease, and hopefully lead to more effective treatments for cancer patients in the future.

Lentiviral-mediated RNA interference of the multifunctional cellular enzyme, glyceraldehyde-3-phosphate dehydrogenase (GAPDH): Impact on the hepatitis C virus life cycle

Hepatits C virus (HCV) causes chronic liver disease, such as cirrhosis (liver disease) and hepatocarcinoma (liver cancer), an irreversible condition that results in liver failure. There is no vaccine or drug available to prevent or treat this infection, which makes HCV the number one cause of liver transplantation in North America. Host proteins are involved in feeding and sheltering organisms such as viruses. Structural and functional studies revealed that a host protein, glyceraldehydes-3-phosphate (GAPDH) interacts with 3’ non-coding region (NCR) of the HCV genome. This multifunctional protein is also shown to associate with genome of several other RNA viruses, such as hepatitis A virus, hepatitis D virus, human parainfluenza virus type 3, and hepatitis B virus, but its function in the virus life cycle is uncertain. Independent of its glycolitic function, this multifunctional protein is also shown to play a role as an apoptosis mediator upon oxidative stress, and is shown to be essential in endoplasmic reticulum (ER) to Golgi transport. This suggests that GAPDH may be involved in several stages of HCV life cycle, such as regulation of translation and replication by interacting with HCV 3’NCR, modulation of liver damage from oxidative stress imposed by HCV encoded proteins, and formation of new virus partivles by budding of nascent HCV genome through the ER. Meera Raj is researching the biological role of GAPDH in the HCV life cycle, which may include regulating viral replication, facilitating viral assembly and modulating viral release from the host cell. In order to show that GAPDH plays a role in HCV life cycle, Meera has prepared human hepatoma (liver) cells showing reduction in GAPDH expression. Her next step is to study the effects of GAPDH reduction on HCV life-cycle. In order to find other host factors that may play a key role in the HCV life-cycle, she will use microarray to study changes in gene expression within HCV infected cells. Her study will provide insight into the HCV biology, host-viral interaction and may provide a potential new strategy for HCV treatment. Establishing GAPDH as a therapeutic target may also provide a broad base therapy for other infections, because targeting host proteins can affect the life cycles of many other viruses.

Molecular Pathways Linking Socioeconomic Status, Stress Experiences, and Asthma Severity in Children

About three million Canadians have asthma, a chronic disease of the airways that causes shortness of breath, tightness in the chest, coughing, and wheezing. The prevalence of asthma among children in the developed world has been rapidly increasing, with up to one in four urban children affected. Research shows that stressful life experiences as well as low socioeconomic status have been linked to poor asthma outcomes in children. To date, few studies have examined the common underlying molecular mechanisms behind these links. Dr. Jutta Wolf is investigating how these two variables — stress experiences and socioeconomic status (SES) — can biologically influence asthma symptoms. Stress can cause immune cells to produce more “cytokine” molecules. Cytokines are proteins that stimulate or inhibit the activity of immune cells, which can aggravate asthma symptoms. Stress is also associated with the release of the hormone cortisol. Jutta is examining whether cortisol is incapable of suppressing a molecule called NF-kappa B, which causes immune cells to produce more cytokines in asthma patients, exacerbating their symptoms. This research could help care providers identify early signs of worsening asthma in children, so their condition can be better managed.

Prosopagnosia and the processing of familiarity, identity and the self

Brain injuries can have lasting detrimental effects on the way someone thinks and behaves. Prosopagnosia, a rare disorder that can result from brain injury, impairs the ability to recognize faces. Patients with this condition may have trouble recognizing family members, coworkers, and even their own face in the mirror. This disorder is debilitating because everyday interactions rely on being able to recognize people. For example, people usually act quite differently when speaking to their boss or their spouse. With her MSFHR award, Kirsten Dalrymple is studying how the healthy brain recognizes faces and how this function is impaired with prosopagnosia (sometimes known as face blindness). Certain brain activations occur when someone looks at a face. Dalrymple will record and compare how brain activations differ between people who have prosopagnosia and those who function normally. In addition, most people remember things better when there’s a connection to themselves, rather than a reference to something unfamiliar, like the face of a stranger. Dalrymple is investigating whether or not this “self-reference” ability is present in people with prosopagnosia, who may be unaware that they are looking at their own face in a picture, rather than the face of a stranger. Her findings could be used to help patients rehabilitate from, or compensate for, the effects of this disorder.

Cognitive, emotional, and behavioural implications of vicarious trauma

Everyone is exposed to stressors in their personal and work lives. How people evaluate and deal with these stressors determines how well they cope, which has implications for their immediate and long term health. Stress can also be less direct, the result of witnessing severe trauma suffered by others, such as the 9/11 attacks on the World Trade Center in New York and London subway attacks in 2005. Research has shown this “vicarious trauma” can also have a substantial impact on health, from post-traumatic stress disorder to depression and persistent worry. Rajiv Jhangiani is studying how individuals react when exposed to trauma indirectly. He is examining how people process information, react emotionally, and make decisions during their exposure to vicarious trauma. Jhangiani is assessing how certain factors influence this reaction and ability to cope, such as identifying with victims, the degree of uncertainty about the situation, information overload, and resilience. This information will help identify how individuals and health and social service providers can support healthy ways of coping with vicarious trauma.

Female sexual arousal disorder subtypes: Conceptualization, diagnosis and treatment

Sexual dysfunctions play a significant role in depression, anxiety, stress, and marital/relationship satisfaction. Female Sexual Arousal Disorder (FSAD) affects approximately 1/4 of women aged 18-59. However, there are no established treatments for this disorder, with drug therapy trials yielding inconclusive and contradictory results. Recently, researchers and clinicians have disputed the current classification of FSAD as it only involves impairments in physiological sexual arousal and ignores the subjective aspect that the majority of women report. As a result, experts in the field have proposed a new classification involving three specific FSAD subtypes. Building on her research as a MSFHR-funded Master’s student, Carolin Klein is conducting a series of three experiments using alternative modes of activating the sympathetic nervous system to extend and replicate previous findings on these subtypes of FSAD. Carolin aims to better understand sexual functioning and the relationship between physiological and subjective sexual arousal in women in order to improve treatments. If further research continues to support the delineation of FSAD into separate subtypes , it may explain why treatments that increase physiological arousal appear to have no, or only a minimal effect on subjective arousal, and vice versa. Accordingly, separate treatments will be needed depending on the FSAD subtype.