James Stafford

Professor, Faculty of Science - Biological Sciences
Associate Chair (Graduate), Faculty of Science - Biological Sciences
Associate Chair (Graduate)

Contact

Professor, Faculty of Science - Biological Sciences
Email
stafford@ualberta.ca
Phone
(780) 492-9258
Address
CW-330 & CW-332 Bio Science - Centre Wing
11355 - Saskatchewan Drive
Edmonton AB
T6G 2E9

Associate Chair (Graduate), Faculty of Science - Biological Sciences
Email
stafford@ualberta.ca

Associate Chair (Graduate)
Email
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 ┬Ám) 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.


Browse more courses taught by James Stafford

Publications

A novel family of diversified immunoregulatory receptors in teleosts is homologous to both mammalian Fc receptors and molecules encoded within the leukocyte receptor complex

Author(s): Stafford JL, Bengten E, Du Pasquier L, McIntosh RD, Quiniou SM, Clem LW, Miller NW
Publication: Immunogentics
Volume: 58
Issue: 9
Page Numbers: 758-773
External Link: http://link.springer.com/article/10.1007/s00251-006-0134-1

Cell surface expression of channel catfish leukocyte immune-type receptors (IpLITRs) and recruitment of both Src homology 2 domain-containing protein tyrosine phosphatase (SHP)-1 and SHP-2

Author(s): Montgomery BCS, Mewes J, Davidson C, Burshtyn DN, Stafford JL
Publication: Developmental & Comparative Immunology
Volume: 33
Issue: 4
Page Numbers: 570-582
External Link: http://www.sciencedirect.com/science/article/pii/S0145305X08002334

Channel catfish leukocyte immune-type receptor mediated inhibition of cellular cytotoxicity is facilitated by SHP-1-dependent and -independent mechanisms

Author(s): Montgomery BC, Cortes HD, Burshtyn DN, Stafford JL
Publication: Developmental & Comparative Immunology
Volume: 37
Issue: 1
Page Numbers: 151-163
External Link: http://www.sciencedirect.com/science/article/pii/S0145305X11002345

Channel catfish leukocyte immune-type receptors contain a putative MHC class I binding site

Author(s): Stafford JL, Bengten E, Du Pasquier L, Miller NW, Wilson M
Publication: Immunogentics
Volume: 59
Issue: 1
Page Numbers: 77-91
External Link: http://link.springer.com/article/10.1007/s00251-006-0169-3

Connected component masking accurately identifies the ratio of phagocytosed and cell-bound particles in individual cells by imaging flow cytometry

Author(s): Fei C, Lillico DME, Hall B, Rieger AM, Stafford JL
Publication: Cytometry Part A
External Link: http://onlinelibrary.wiley.com/doi/10.1002/cyto.a.23050/full

Examination of the stimulatory signaling potential of a channel catfish leukocyte immune-type receptor and associated adaptor

Author(s): Cortes HD, Montgomery BC, Verheijen K, Garcia-Garcia E, Stafford JL
Publication: Developmental & Comparative Immunology
Volume: 36
Issue: 1
Page Numbers: 62-73
External Link: http://www.sciencedirect.com/science/article/pii/S0145305X11001704

Identification and Characterization of a FcR Homolog in an Ectothermic Vertebrate, the Channel Catfish (Ictalurus punctatus)

Author(s): Stafford JL, Wilson M, Nayak D, Quiniou SM, Clem LW, Miller NW, Bengten M
Publication: The Journal of Immunology
Volume: 177
Issue: 4
Page Numbers: 2505-2517
External Link: http://www.jimmunol.org/content/177/4/2505.full

Imaging flow cytometry and GST pulldown assays provide new insights into channel catfish leukocyte immune-type receptor-mediated phagocytic pathways

Author(s): Zwozdesky MA, Fei C, Lillico DME, Stafford JL
Publication: Developmental & Comparative Immunology
Volume: 67
Page Numbers: 126-138
External Link: http://www.sciencedirect.com/science/article/pii/S0145305X16303743

Induction of Phagocytosis and Intracellular Signaling by an Inhibitory Channel Catfish Leukocyte Immune-Type Receptor: Evidence for Immunoregulatory Receptor Functional Plasticity in Teleosts

Author(s): Cortes HD, Lillico DME, Zwozdesky MA, Pemberton JG, O'Brien A, Montgomery BCS, Wiersma, L, Chang JP, Stafford JL
Publication: Journal of Innate Immunity
Volume: 6
Page Numbers: 435-455
External Link: http://www.karger.com/Article/Abstract/356963

Biochemical and Functional Insights into the Integrated Regulation of Innate Immune Cell Responses by Teleost Leukocyte Immune-Type Receptors

Author(s): Fei C, Pemberton JG, Lillico DME, Zwozdesky MA, Stafford JL
Publication: Biology
Volume: 5
Issue: 1
Page Numbers: 13
External Link: http://www.mdpi.com/2079-7737/5/1/13/htm

Teleost IgSF immunoregulatory receptors

Author(s): Montgomery BCS, Cortes HD, Mewes-Ares J, Verheijen K, Stafford JL
Publication: Developmental & Comparative Immunology
Volume: 35
Issue: 12
Page Numbers: 1223-1237
External Link: http://www.sciencedirect.com/science/article/pii/S0145305X1100070X

Stimulatory catfish leukocyte immune-type receptors (IpLITRs) demonstrate a unique ability to associate with adaptor signaling proteins and participate in the formation of homo- and heterodimers

Author(s): Mewes J, Verheijen J, Montgomery BCS, Stafford JL
Publication: Molecular Immunology
Volume: 47
Issue: 2
Page Numbers: 318-331
External Link: http://www.sciencedirect.com/science/article/pii/S0161589009007160

Teleost leukocyte immune-type receptors activate distinct phagocytic modes for target acquisition and engulfment

Author(s): Lillico DME, Zwozdesky MA, Pemberton JG, Deutscher JM, Jones LO, Chang JP, Stafford JL
Publication: Journal of Leukocyte Biology
Volume: 98
Issue: 2
Page Numbers: 235-248
External Link: http://www.jleukbio.org/content/98/2/235.full

Trypsin differentially modulates the surface expression and function of channel catfish leukocyte immune-type receptors

Author(s): Lillico DME, Pemberton JG, Stafford JL
Publication: Developmental & Comparative Immunology
Volume: 65
Page Numbers: 231-244
External Link: http://www.sciencedirect.com/science/article/pii/S0145305X16302312