James Stafford
Contact
Professor, Faculty of Science - Biological Sciences
- stafford@ualberta.ca
- Phone
- (780) 492-9258
- Address
-
CW-330 & CW-332 Bio Science - Centre Wing
11355 - Saskatchewan DriveEdmonton ABT6G 2E9
Associate Chair (Graduate)
- stafford@ualberta.ca
Overview
About
BSc
Medical Laboratory Sciences, University of Alberta
PhD
Physiology and Cell Biology, Department of Biological Sciences, University of Alberta
Postdoc
University of Mississippi Medical Center, Jackson, MS, USA
Research
| Innate immunity is an essential component of the vertebrate antimicrobial defense system. This protection depends on the integrated activity of highly specialized immune cell-types that are responsible for the recognition and clearance of pathogens. One of these fundamental innate cell responses is called phagocytosis (immune cell eating), which involves dynamic remodeling of the plasma membrane during the capture and ingestion of extracellular material. Phagocytosis is an ancient cellular process that was established for simple nutrient acquisition in primitive unicellular organisms, but has since evolved into a complex immune defense response utilized by all multicellular animals. Cells that perform phagocytosis are collectively known as phagocytes and their unique ability to engulf large (>0.5 µm) particulate targets is dependent on the expression of distinct immune receptor-types. The best-characterized phagocytic receptors include the mammalian complement receptors (CR), dectin-1, and members of the Fc receptor (FcR) family. Studies from these model immune proteins have identified phagocytosis as a temporally coordinated process that tightly regulates plasma membrane remodelling events during the capture, ingestion, and eventual destruction of microbes. Each phagocytic receptor-type relays extracellular target binding into dynamic filamentous (F)-actin-mediated remodelling of the plasma membrane through specific intracellular signaling events. Despite the recognized diversity in receptor-mediated phagocytic signaling, phagocytic pathways generally require tyrosine kinase activity, localized phospholipid metabolism, activation of Rho-family small GTPases, and the engagement of various actin nucleation and regulatory factors. Importantly, the molecular components that regulate phagocytosis are also vital for many other biological responses, including: cell adhesion and migration, wound repair, and the clearance of debris from tissues. As a result, phagocytosis is not only an excellent model for studying receptor-mediated signaling events in immunity, but also for investigating fundamental aspects of the regulatory machinery involved in the control of plasma membrane dynamics. Despite an in-depth understanding of phagocytosis in mammals, very little is currently known in basal vertebrates. Interestingly, there are more than 25,000 known species of teleost fishes that thrive in diverse aquatic ecosystems populated with numerous bacterial, parasitic, and viral pathogens. Fish exhibit robust innate immune mechanisms that deal with this continuous assault, including phagocytosis, but how these responses are specifically regulated in ectothermic vertebrates is largely unknown. Genome sequencing has recently revealed a vast inventory of fish immune genes, including a large number and diversity of immune receptor-types. However, the functional roles played by these teleost receptor proteins remains to be determined. In an effort to understand conserved and divergent aspects of innate immune processes across vertebrates, my research has focused on the characterization of channel catfish (Ictalurus punctatus) leukocyte immune-type receptors (IpLITRs). These efforts have recently uncovered new details regarding teleost immunoregulatory-mediated signaling pathways and their functional capabilities. My ongoing research program uses IpLITR proteins as an innate receptor model system to study immunregulatory receptor signaling events in vertebrates. Please see Featured Publications and the Stafford LAB page for further details about our research. |
Courses
BIOL 298 - Understanding Biological Research
An introduction to the process of scientific research including the different approaches to research within biology, formulating research questions, hands-on skill development, experimental design, data collection and analysis, critical thinking, communication of findings, ethics, and career opportunities. Students will attend lectures and selected seminars, and participate in biological research under the supervision of an academic staff member in the Department of Biological Sciences. Open to undergraduate students in the Faculty of Science with preference given to students in Honors and Specialization Programs in the Department of Biological Sciences, and BSc General students (Biological Sciences major). Consent of Department of Biological Sciences required. All students must apply for admission. Prerequisite: BIOL 107 or 108 or SCI 100. See the Biological Sciences website for more details at www.biology.ualberta.ca/courses.
BIOL 698 - Undergraduate Research Mentoring
A credit/no-credit course for graduate students who are mentoring undergraduates in a research course (BIOL 398, 490 and 498) under the supervision of an academic member of the Department of Biological Sciences. Mentorship includes activities such as in lab or field supervision, training, and help with reports and presentations. Consent of Department of Biological Sciences required. Can be taken in any year. Credit may be obtained more than once.
BIOL 699B - Undergraduate Research Mentoring
A credit/no-credit course for graduate students who are mentoring undergraduates in a research course (BIOL 399 and 499) under the supervision of an academic member of the Department of Biological Sciences. Mentorship includes activities such as in lab or field supervision, training, and help with reports and presentations. Consent of Department of Biological Sciences required. Can be taken in any year. Credit may be obtained more than once.
IMIN 371 - Introduction to Immunology
Survey course introducing the student to immunological concepts. Topics include the clonal selection theory, antibody structure and specificity, genetic basis of immune diversity, antibody-antigen reactions, cell interactions in immune responses, the molecular basis of non-self recognition, MHC molecules and transplantation, tolerance, effector mechanism of immunity, hypersensitivity and immunodeficiency. Prerequisites: BIOCH 200 or 205, BIOL 207, and IMIN 200. May not be taken for credit if credit already obtained in INT D 371. (Offered jointly by the Department of Biological Sciences and the Department of Medical Microbiology and Immunology.) [Biological Sciences]
IMIN 372 - Research Techniques in Immunology
A lecture and laboratory course covering theory and practice behind selected immunological techniques. Techniques covered may include: lymphocyte isolation, flow cytometry, mixed lymphocyte reactions, immunocytochemistry, immunoprecipitation, ELISA, western blotting, expression cloning and monoclonal antibody technology. Labs will sometimes require students to return the next day to check on plates or cultures. Prerequisite: IMIN 371. May not be taken for credit if credit already obtained in INT D 372. (Offered jointly by the Departments of Biological Sciences and Medical Microbiology and Immunology). [Biological Sciences]
IMIN 405 - Innate Immunity
This course covers topics of innate immunity with emphasis on strategies for pathogen recognition, local and systemic activation of the innate immune response, and regulation of innate effector mechanisms. Innate defense strategies against pathogens as well as detection and elimination of tumors will also be covered. Lectures will be followed by active discussions of selected readings pertaining to current research in the subject area. Prerequisites: IMIN 371 or consent of instructor. Credit cannot be obtained for both IMIN 405 and 505. (Offered jointly by the Departments of Biological Sciences and Medical Microbiology and Immunology). [Biological Sciences].
IMIN 505 - Advanced Innate Immunity
This course covers topics of innate immunity with emphasis on strategies for pathogen recognition, local and systemic activation of the innate immune response, and regulation of innate effector mechanisms. Innate defense strategies against pathogens as well as detection and elimination of tumors will also be covered. Lectures will be followed by active discussions of selected readings pertaining to current research in the subject area. Lectures and graded discussions are the same as for IMIN 405 but with evaluation appropriate for graduate students. Prerequisites: consent of instructor. Credit cannot be obtained for both IMIN 405 and 505. (Offered jointly by the Departments of Biological Sciences and Medical Microbiology and Immunology). [Biological Sciences].
ZOOL 242 - Animal Physiology II: Intercellular Communication
Endocrinology, immunology and neural, sensory, motor, and reproductive physiology. Examples from invertebrates and vertebrates. Prerequisite: BIOL 107 or SCI 100. This course may not be taken for credit if credit has been obtained in PHYSL 210 or 214.