Stephanie DeWitte-Orr

My research program focuses on the innate antiviral immune response of animals. Viruses make double-stranded (ds)RNA during their replication within a host cell. We use cutting edge techniques from the fields of cell biology, virology and molecular biology to study 1) the production of dsRNA by viruses and 2) the detection and response to viral dsRNA by the host cell. A better understanding of the innate immune response to virus infections is leading our development of novel therapeutics such as antiviral drugs and vaccine adjuvants for both human and farmed animals. We are also using dsRNA to knockdown virus replication and to kill cancer cells. Our dsRNA molecules are in pre-clinial trials as an inhaled trivalent antiviral therapeutic and an ovarian cancer treatment. 

• University Research Professor Award, Wilfrid Laurier University (2022).
• Robert G. Boutilier New Investigator award, Canadian Society of Zoology (2018).
• Early Career Researcher Award, Wilfrid Laurier University (2018).
• Early Researcher Award, Ministry of Research, Innovation and Science (2016).
• Young Scientist Award, Society for In Vitro Biology (2014).

I support a number of different research positions within my laboratory including graduate students, undergraduate 4th year thesis students and volunteer positions. Please email me if you are interested in my research program, describing to me your research background, scientific interests and GPA. 

For 2025/2026 Undergraduate research opportunities please see below:

*** Applying for Undergraduate research opportunities for 2025/2026 are now open ***

If you are interested in doing a 4th year thesis project or a two term 0.5 directed studies project with me and my team in starting September 2025, please submit the following documents in an email to me (sdewitteorr@wlu.ca) by February 15th, 2025:

1) A short paragraph or two describing: (i) why you want to do research and why with my team, (ii) what research you have done thus far, (iii) what is your plan after graduating (ie. how does a research experience fit into your career goals) and (iv) any specific circumstances I should know regarding your application package (will be kept confidential)

2) A CV or resume

3) a copy of your unofficial transcript

I will be contacting students for chats end of February. If you haven't been contacted, unfortunately we won't have a position for you this year. There will be 2-3 spots available for undergraduate students this coming year.

All undergraduates will be paired with a graduate student mentor. You will be given your own project, working on innate immune responses to virus infections and will learn cell culture, virology, molecular biology and microscopy skills. Some projects will have an opportunity to work with industrial partners. Any data generated by you while working in the lab that contributes to a paper will earn you authorship on that paper. 

• Daniels DE, Portelli IV, Au SKW, DeWitte-Orr SJ (2024). Production, isolation and detection of poly IC in extracellular vesicles from U937 cells. Edition: Intracellular Pathogens, Methods in Molecular Biology. Thakur, A (ed). Springer Nature. p. 235-244.
• Jenik K, Oberhoffner S, DeWitte-Orr SJ (2024) Response to pathogens – innate immunity (Volume 1, Chapter 10019). In: Encyclopedia of Fish Physiology, Second Edition. Alderman SL and Gillis TE (ed). Elsevier. p. 334-345.
• Poynter SP and DeWitte-Orr SJ (2017) Visualizing virus-derived dsRNA using antibody-independent and –dependent methods (Chapter 5). In: Innate antiviral immunity: methods and protocols. Mossman, K (ed). Springer. p. 103-118.

Selected Research Articles Published

• Oberhoffner SJ, Daniels DE, Cooper E, Ijaz A, Richardson SA, DeWitte-Orr SJ (2024) Using cationic liposomes as carrier for long dsRNA to trigger an antiviral response in rainbow trout cell lines. In Vitro Cellular and Developmental Biology – Animal. In press.
• Samms KA, Monod EC, Ijaz A, Au SKW, Jenik K, Rodriguez-Ramos T, Dixon B, DeWitte-Orr SJ (2025) Sequence independent immune effects of White spot syndrome virus (WSSV) dsRNA complexed with phytoglycogen nanoparticles in freshwater crayfish. Journal of Invertebrate Pathology. 209: 108239.
• Jenik K, Poynter SJ, Herrington-Krause SL, Samms KA, Sanchez Diaz N, DeWitte-Orr SJ (2024) Examining rainbow trout vig-3 expression patterns in vitro following treatment with type I IFN, dsRNA and viral infection. Comparative Immunology Reports. 6, 200135.
• Betancourt JL, Monod EC, Samms KA, Alkie TA, Walmsley CG, Rogriguez-Ramos T, DeWitte-Orr SJ, Dixon B. (2024) Immunostimulant effects of Pituitary Adenylated Cyclase-Activating Polypeptide and double-stranded (ds)RNA in Orconectes propinquus. Fish and Shellfish Immunology. 145:109388.
• Vo, NTK, DeWitte-Orr SJ (2023). Cytotoxicity of the field lampricide 3-trifluoromethyl-4-nitrophenol (TFM) in tadpole cell lines from North American frogs. In Vitro Cellular & Developmental Biology – Animal. 59(10):790-795.
  • Selected as a Journal Highlight, featured articles on SIVB’s website
• Vo,NTK, Leis E, DeWitte-Orr SJ (2023). Hypersensitive response to interferon-stimulated gene (ISG)-inducing double- stranded RNA in American bullfrog tadpole fibroblasts. Developmental and Comparative Immunology. 148: 104918.
• Lewis A, Tran A, L’Lador N, Jadaa N, Moore E, DeWitte-Orr SJ, Poynter SJ (2023). Phytoglycogen-dsRNA nanoparticles demonstrate differential cytotoxicity and immunostimulatory potential in two ovarian cancer cell lines. Journal of Nanoparticle Research.25,104. https://doi.org/10.1007/s11051-023-05758-7.
• Au SK, Portelli IV, DeWitte-Orr SJ. (2022) Using long, sequence specific dsRNA to knockdown inducible protein expression and virus production via an RNAi-like mechanism. Fish and Shellfish Immunology. In Press.
• Semple SL, Alkie TN, Jenik K, Warner BM, Tailor N, Kobasa D, DeWitte-Orr SJ. (2022) More tools for our toolkit: the application of HEL-299 cells and dsRNA-nanoparticles to study human coronaviruses in vitro. Virus Research. In Press.
• Whittal MC, Poynter SJ, Samms K, Briar KJ, Sinopoli SI, Millecaps M, Stone LS, DeWitte-Orr SJ, Gregory DE. (2022) TAK-242 treatment and its effect on mechanical properties and gene expression associated with IVD degeneration in SPARC-null mice. European Spine Journal. In Press.
• Semple SL, Jacob RA, Mossman KL, DeWitte-Orr SJ. (2022) Discovery and use of long dsRNA mediated RNA interference (dsRNAi) to stimulate antiviral protection in interferon competent mammalian cells. Frontiers in Immunology – Molecular Innate Immunity. May 6; 13:859749.
• DeWitte-Orr SJ and Whiteside A. (2022) COVID-19: Where we’ve been, where we’re going. Balsillie Papers. 4(6): 1-15.
• Molladavoodi S, DeWitte-Orr SJ, Gregory DE. (2022) An In Vitro 3D Annulus Fibrosus Cell Culture Model with Type I Collagen: An Examination of Cell-Matrix Interactions. JOR Spine. 5(1): e1193.
• Samms K, Alkie TN, Jenik K, DeJong DJ, Klinger KM, DeWitte-Orr SJ. (2022) Oral delivery of a dsRNA-phytoglycogen nanoparticle complex enhances both local and system innate immune responses in rainbow trout. Fish and Shellfish Immunology. 121:215-222.
• Delumeau L-V, Asgarimoghaddam H, Alkie TN, Jones A, Lum S, Mistry K, Aucoin M, DeWitte-Orr SJ, and Musselman K. (2021) Effectiveness of antiviral metal and metal oxide thin film coatings against human coronavirus 229E. APL Materials. 9(11):111114.
• Jenik K, Alkie TN, Samms K, Lalousis A, Moore E, DeJong DJ, DeWitte-Orr SJ. (2021) In  vitro and in vivo characterization of inosine monophosphate delivered by a phytoglycogen  nanoparticle in rainbow trout (Oncorhynchus mykiss). North American Journal of Aquaculture. 84(2): 156-164.
• Jenik K, Alkie TN, Moore E, DeJong JD, Lee LEJ, DeWitte-Orr SJ. (2021) Characterization of a bovine intestinal myofibroblast cell line and stimulation using phytoglycogen-based nanoparticles bound to inosine monophosphate. In Vitro Cellular and Developmental Biology – Animal. 57(1), 86-94.
• Alkie TN, DeJong JD, Moore E, DeWitte-Orr SJ. (2020) Phytoglycogen nanoparticle delivery for inorganic selenium reduces cytotoxicity without impairing selenium bioavailability. International Journal of Nanomedicine. 15: 10469-10479.
• Zwambag DP, Laird BN, DeWitte-Orr SJ, Gregory DE. (2020) Unloaded organ culturing has a detrimental effect on the axial mechanical properties of the intervertebral disc. Journal of Biomechanical Engineering. 143(8):08501.
• Bienentreu JF, Guerreiro MJ, Grayfer L, Robert J, Brunetti CR, Schock DM, DeWitte-Orr SJ, Lesbarreres D. (2020) Sublethal effects of wild-type and vIF-2alpha-knockout Frog virus 3 in post-metamorphic wood frogs (Rana sylvatica): potential for a stage-specific reservoir. FACETS. 5(1) 738-757.
• Zwambag DP, Molladavoodi S, Guerreiro MJ, Laird BN, DeWitte-Orr SJ, Gregory DE. (2020) Immuno-stimulatory capacity of decorin in the intervertebral disc and the mechanical consequence of resultant inflammation. European Spine Journal 29(7):1641-1648.
• DeWitte-Orr SJ, Edholm ES, Grayfer L. (2019) Editorial: Innate immunity of aquatic vertebrates. Frontiers in Immunology. 10:2959.
• Alkie TN, DeJong JD, Jenik K, Klinger K, DeWitte-Orr SJ. (2019) Enhancing innate antiviral immune responses in rainbow trout by double-stranded RNA delivered with novel phytoglycogen nanoparticles. Scientific Reports. 9: 13619.
• Poynter SJ, Herrington-Krause S, DeWitte-Orr SJ. (2019) Two DExD/H-box helicases, DDX3 and DHX9, identified in rainbow trout are able to bind dsRNA. Fish and Shellfish Immunology. 93:1056-1066.
• Vo NTK, Everson J, Moore L, DeWitte-Orr SJ. (2019) Class A scavenger receptor expression and function in eight novel tadpole cell lines from the green frog (Lithobates clamitans) and the wood frog (Lithobates sylvatica). Cytotechnology. 6:757-768.
• Vo NTK, Guerreiro M, Yaparla A, Grayfer L, DeWitte-Orr SJ. (2019) Class A scavenger receptors are used by Frog virus 3 during its cellular entry. Viruses. 11:93.
• Vo NTK, Moore LC, Leis E, DeWitte-Orr SJ. (2019) Class A scavenger receptors mediate extracellular dsRNA sensing, leading to downstream antiviral gene expression in a novel American toad cell line, BufoTad. Developmental and Comparative Immunology. 92: 140-149.

HE303/BI317 - Immunology

HE470/HE432 - Biomedical Virology

•  Podcast, October 19, 2022, ‘Chitchatting and Questioning the World, episode: The Dance of our Cells’ with Ariella Rukhlin. https://www.chitchatworld.org/episodes/a8k9nmvjwhop4setadb0dbj34ljilx 
• Global Affairs Canada, Division of Education, featured me and my work on their social media platforms, November 1, 2022, to promote Canada as a study destination for international students.
  LinkedIn:
  ENG: https://www.linkedin.com/feed/update/urn:li:activity:6993195310810374144
  FRE: https://www.linkedin.com/feed/update/urn:li:activity:6993195309195546624
  Facebook:
  ENG: https://www.facebook.com/photo.php?fbid=505124784966283&set=a.307732001372230&type=3
  FRE: https://www.facebook.com/photo.php?fbid=510066087801871&set=a.313728654102283&type=3
  Instagram:
  ENG: https://www.instagram.com/p/Cka1R27MuUa/
  FRE: https://www.instagram.com/p/Cka1R89gWW5/
• Laurier professors receive over $500,000 in support from Ontario Ministry of Research and Innovation.