Publications: Pauline Johnson's Publications
Office #: 604-822-8980
Office: Room 3502, 2350 Health Sciences Mall, Life Sciences Centre
The Johnson lab
We are located on the third floor of the Life Sciences Centre at the main campus of the University of British Columbia. We are an immunology lab that uses in vitro and in vivo model systems to study immune functions and interactions, in both health and disease. We use a variety of molecular, cellular and immunological approaches that include the latest multi-color flow cytometry and confocal microscopy techniques. For further information, see below, and check out our recent publications and our research page. Please email Pauline Johnson if you want more information regarding any available lab positions, i.e. post-doc, graduate and undergraduate student positions.
One major research focus of the lab is to understand the contributions of macrophages to inflammation, fibrosis and cancer metastasis. A second research focus is to determine the function of hyaluronan in these processes, and to understand macrophage-hyaluronan interactions.
We currently focus on lung infection, lung inflammation and cancer metastasis to the lung.
Our lab is investigating the function of macrophages in the healthy and inflamed lung, and their contributions to fighting infections, inducing and resolving inflammation and fibrosis in the lung. We are interested in the contributions of monocyte-derived macrophages and alveolar macrophages to these processes. We are also interested in the interactions of macrophages with hyaluronan, a key component of extracellular and peri-cellular matrices. Hyaluronan is upregulated on tissue infection or injury and its expression correlates with the immune infiltrate. Hyaluronan is implicated in both inflammation and tissue repair, yet its function and relationship with immune cells is poorly understood. Our lab is interested in understanding immune cell interactions with their environment and how their niche supports their survival and function. CD44 is a key receptor for hyaluronan on immune cells where its interaction is highly regulated. Typically, activated T cells and macrophages engage hyaluronan, but the consequences of this are still poorly understood.
We are also interested in understanding the contributions of macrophages and hyaluronan to cancer metastasis. We collaborate with the Roskelley lab here at UBC to study melanoma metastasis to the lung.
The Immune system
Our immune system does an incredible job to keep us healthy and free from both infectious diseases and cancer, and also plays a key role in tissue repair. It is made up of the innate and adaptive immune systems, which together provide an effective and powerful tools to keep us healthy. Macrophages are innate immune cells that act as sentinels, particularly in mucosal tissues, They not only help protect us against infection and aid in tissue repair, but also have roles in maintaining tissue homeostasis. There are many different kinds of macrophages in the body, some are tissue resident, such as alveolar macrophages, that like stem cells, have the ability to self-renew for the lifetime of the host, whereas others differentiate from bone marrow derived monocytes.
Many diseases have an inflammatory component, and chronic inflammatory diseases are a major health problem; they are progressive and there is no cure. In order to find effective treatments, it is first neccessary to perform fundamental basic research to better understand the cause and progression of the inflammatino process and what leads to a lack of resolution and a chronic inflammatory state. Our lab focuses on the function of macrophages in this process, and the contributions of the extracellular matrix, which is remodeled during infection and repair.
Inflammation is an immediate response to infection or tissue injury. It is normally a beneficial response that results in recruitment of immune cells to the site of injury to fight infection. These cells also aid in tissue repair and the resolution of inflammatory response. The persistence of inflammation leads to chronic inflammatory diseases such as arthritis, inflammatory bowel diseases and atherosclerosis. These are an increasing problem in the Western world and cost our health system billions in long term care.
Cancer metastasis and the contributions of hyaluronan and macrophages
Inflammation results in increased levels of hyaluronan and the recruitment of immune cells such as monocyte-derived macrophages to the site of injury where they are actively involved in clearing infections and then later in tissue remodeling and repair. This creates a rich environment that promotes cell turnover and proliferation and we are interested in understanding the impact inflammation has on cancer metastasis. Both hyaluronan and tumor associated macrophages have been implicated in promoting tumor growth and we want to understand this process at a molecular level, so we can better understand the metastatic process and find new avenues for limiting metastatic spread.