CONTACT INFO

Lijuan Yuan, PhD
Professor, Virology and Immunology
Department of Biomedical Sciences and Pathobiology
Email: lyuan@vt.edu

About the Yuan Laboratory

The mission of Dr. Yuan’s laboratory is to study the pathogenesis and immunity of enteric pathogens and to develop novel prophylactics and therapeutics against enteric viruses.

Research interests

  • Pathogenesis and innate and adaptive immune responses induced by enteric viruses (i.e., norovirus and rotavirus) in gnotobiotic pig models of human enteric virus infection and diseases
  • The development of passive immune prophylactics and therapeutics against diarrheal pathogens
  • The development of more effective vaccines against viral gastroenteritis

* For more details, see "Research interests" dropdown.

Virology and immunology techniques used in the Yuan Lab's research

Virology and immunology techniques used in the Yuan Lab's research

A) Rotavirus particles in fecal samples detected by immune electron microscopy
B) Rotavirus replication in porcine jejunum epithelial cells detected by immunofluorescence staining
C) Cytopathological changes in porcine small intestinal epithelium caused by human norovirus infection observed under transmission electron microscopy
D) Immune cell analysis and sorting by flow cytometry
E) Antibody secreting cells detected by ELISPOT assay
F) Real-time PCR melting curve for detection and quantitation of human norovirus.

Dr. Yuan’s lab studies enteric viruses and develop prophylactics and therapeutics against viral diarrheal diseases. The lab's research interests are focused on pathogenesis and innate and adaptive immune responses induced by enteric viruses (i.e., norovirus and rotavirus), the development of passive immune prophylactics and therapeutics, and the development of safer and more effective vaccines against viral gastroenteritis.

Dr. Yuan has a long-standing interest in enteric viral vaccines. She has studied intestinal and systemic immune responses induced by various rotavirus and norovirus vaccines and their protective efficacy against the viral infections and diarrhea. These studies have included attenuated, reassortant, inactivated, recombinant protein (P2-VP8*), DNA plasmid, virus-like particle, P particle, nanoparticle (P24-VP8* and S60-VP8*), and mRNA vaccines with different adjuvants (Alum, LT-R192G, ISCOM, MPL, chitosan, rice bran and probiotics) and immunization routes (oral, intramuscular, intranasal, intradermal by gene gun) with or without maternal immunomodulators (antibodies and cytokines).

Currently, the Yuan lab is evaluating the immunogenicity and protective efficacy of several candidate rotavirus and norovirus vaccines, and a novel passive prophylaxis against both noroviruses and Clostridium difficile by engineered probiotic yeast Saccharomyces boulardii secreting multi-specific single-domain antibodies.

Dr. Yuan's research projects have been funded by National Center for Complementary and Alternative Medicine, NIH (R21AT002524 and R01AT004789); National Institute of Allergy and Infectious Diseases, NIH (R01AI148357; R01AI089634 subcontract; 2R44AI118009 subcontract; R56AI148426 subcontract; CRDF Global); Office of Director, NIH (R21OD019934A); PATH (Program for Appropriate Technology in Health); Bill & Melinda Gates Foundation (Grand Challenges Explorations Phase I and Phase II); Cincinnati Children's Hospital Medical Center, OH; Lanzhou Institute of Biological Products, China; Anhui Zhifei Longcom Biopharmaceutical, China; and CureVac GmbH, Germany.

Rotaviruses belong to the Reoviridae family, which possess a segmented double-stranded RNA genome.

Rotaviruses infect and replicate in the villous enterocytes of the small intestine, causing structural and functional changes of the intestinal epithelium and diarrhea. 

Rotavirus infection is the most common cause of severe viral gastroenteritis in children under 5 years of age in the United States, leading to a tremendous disease burden with costs to health care and society exceeding $1 billion annually. Rotavirus causes even more-immense morbidities and mortalities in developing countries.

Vaccination is recognized as the only control measure having a significant impact on the incidence of rotavirus gastroenteritis and is considered the first-line strategy for disease prevention. However, the current vaccines provide only  30-42% protection rate against rotavirus gastroenteritis in the poorest Asian and African countries where rotaviruses cause the highest numbers of mortality among the estimated 200,000 deaths due to rotavirus infection globally each year.

The Yuan Lab uses the gnotobiotic pig model of human rotavirus infection and disease to characterize the safety, immunogenicity, and broadness of various novel rotavirus vaccines. The gnotobiotic pig model of human rotavirus infection and disease is considered the best animal model for the pre-clinical evaluation of efficacies of human rotavirus vaccines.

Noroviruses (NoVs) are single-stranded, positive-sense RNA viruses belonging to the Caliciviridaefamily. NoVs cause more than 90% of non-bacterial epidemic acute gastroenteritis, affecting people of all ages worldwide. In children, NoV is one of the leading etiological agents (next to rotavirus) causing dehydrating diarrhea.

The symptoms of NoV infection in humans are sudden onset and frequent vomiting and diarrhea that often lead to dehydration. Globally, HuNoV causes an estimated 699 million cases of illness and 219,000 deaths each year.

Noroviruses are highly contagious and can be spread quickly by person-to-person transmission, through contact with contaminated environmental surfaces, or by contaminated food and water, which are common sources of large outbreaks in a variety of settings. These outbreaks are especially prevalent in semi-closed communities, such as hospitals, cruise ships, nursing homes, the military, and schools.

The Yuan Lab has established the gnotobiotic pig model of human norovirus infection and disease. The animal model is used to characterize the safety, immunogenicity, and broadness of candidate norovirus vaccines and in the evaluation of passive prophylaxis in protection against various noroviruses.

2022

2019

  • Dr. Yuan was elected as a Council Member of US Association for Gnotobiotics

2018

  • Ashwin Ramesh won the Outstanding Ph.D. Poster Award for his presentation “Quadrivalent human norovirus-like particle (VLP) vaccine induces VLP-specific IFN-γ producing T cell responses in systemic lymphoid tissues of gnotobiotic pigs” at the 29th Annual Research Symposium, Virginia-Maryland College of Veterinary Medicine. Blacksburg, Virginia. March 15, 2018.
  • Ashwin Ramesh won the Society for Leukocyte Biology Trainee Award for his presentation “Quadrivalent human norovirus-like particle (VLP) vaccine induces VLP-specific IFN-γ producing T cell responses in systemic lymphoid tissues of gnotobiotic pigs” at the 29th Annual Research Symposium, Virginia-Maryland College of Veterinary Medicine. Blacksburg, Virginia. March 15, 2018. 

2017

  • Dr. Lijuan Yuan received the Outstanding Graduate Mentor Award 2016-2017, Biomedical and Veterinary Sciences Graduate Program, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, March 2017.
  • Shaohua Lei received the Outstanding Ph.D. Student Award 2016-2017, Biomedical and Veterinary Sciences Graduate Program, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, March 2017.

2016

  • Erica Twitchell received the Outstanding Ph.D. Student Poster Award for her presentation, “Modeling human enteric dysbiosis and rotavirus immunity in gnotobiotic pigs,” 27th Annual Research Symposium, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, March 17, 2016.
  • Ashwin Ramesh received the Outstanding Ph.D. Student Poster Award for his presentation, “Rice bran and probiotics stimulate strong intestinal IFN-γ producing T-cell responses and reduce norovirus infection in gnotobiotic pigs,” 27th Annual Research Symposium, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, March 17, 2016.
  • Mariah Weiss received the Outstanding Co-Worker Recognition Award at the 27th Annual Research Symposium, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, March 17, 2016.

2015

  • Undergraduate student Christine Tin was among three Virginia Tech students awarded a Barry M. Goldwater Scholarship for the 2015-16 academic year.
  • Ph.D. student Erica Twitchell’s grant application was selected to receive VT Graduate Research Development Fund (May 5, 2015).
  • Ph.D. student Jacob Kocher’s first author paper in Journal of Virology 2014;88(17):9728-43, “Intranasal P particle vaccine provided partial cross-variant protection against Human GII.4 norovirus diarrhea in gnotobiotic pigs,” was selected as a Key Scientific Article contributing to excellence in biomedical research. The article is featured online at Global Medical Discovery [ISSN 1929-8536].

2014

  • Mariah Weiss, Lab and Research Specialist I, was recognized for Outstanding Performance in a Lab.
  • Dr. Yuan won the Grand Challenges Explorations Round 12 grant for research in global health and development from the Bill and Melinda Gates Foundation. 
  • Ph.D. student Jacob Kocher won a Graduate Student Travel Award to present his research on “P particle vaccine protects against cross-variant norovirus infection and disease in a dose-dependent manner in gnotobiotic pigs” at the 33rd American Society for Virology Annual Meeting, June 21-25, 2014,  Colorado State University, Fort Collins, Colorado.
  • Ph.D. student Xingdong Yang won a Graduate Student Travel Award to present his research on “Neonatal gnotobiotic pig model of human enterovirus 71 infection and immune responses” at the 33rd American Society for Virology Annual Meeting, June 21-25, 2014, Colorado State University, Fort Collins, Colorado.
  • Undergraduate student Christine Tin won third place for her poster “LGG as a vaccine adjuvant in a novel human gut microbiota associated gnotobiotic pig model” at the ILSB Research Poster Symposium, May 1, 2014, Blacksburg, VA.
  • Christine Tin was among three students to present their work at the 2014 National Conference on Undergraduate Research.

2012

  • Post-doctoral associate Ke Wen’s first author paper in Vaccine 2012 Feb 1;30(6):1198-207, “High dose and low dose Lactobacillus acidophilus exerted differential immune modulating effects on T cell immune responses induced by an oral human rotavirus vaccine in gnotobiotic pigs,” was selected as a Key Scientific Article contributing to excellence in biomedical research. The article is featured online at Global Medical Discovery.

2011

  • Dr. Yuan received the prestigious Pfizer Award for Research Excellence.
  • Yuan Lab research on probiotics is featured in an article, “Pros of Probiotics,” by International Innovation–Healthcare (2011 Issue 1, page 90).

2010

  • Dr. Lijuan Yuan was selected as Scholar of the Week by the Office of the Vice President for Research at Virginia Tech, recognizing her research to develop rotavirus and norovirus vaccines.
  • Tammy Bui won a Graduate Student Travel Award to present her research on study of infection and illness of eight norovirus GII.4 variants in a gnotobiotic pig challenge model, 29th American Society for Virology Annual Meeting, July 17-21, 2010, Montana State University, Bozeman, Montana.
  • Ke Wen won a Graduate Student Travel Award to present his research on Toll-like receptor 2, 3 and 9 expression and IFN-γ production by gd T cell subsets in gnotobiotic pigs infected with virulent human rotavirus, 29th American Society for Virology Annual Meeting, July 17-21, 2010, Montana State University, Bozeman, Montana.
  • Ke Wen won a Veterinary Virology Club Travel Award for his research on gd T cell subsets, 29th American Society for Virology Annual Meeting, July 17-21, 2010, Montana State University, Bozeman, Montana.
  • Dorothy 'Nezzie' Jones, who previously worked for six months as a volunteer in the Yuan Lab, applied successfully for the Summer Veterinary Student Research Program, which is sponsored by the National Institutes of Health and the Merial Veterinary Scholars Program.

2009

  • Dr. Lijuan Yuan received the American Society for Microbiology International Professorship Award for Asia.
  • Dr. Lijuan Yuan was awarded an Honorary Professorship by Yunnan Agricultural University in China.
  • Instructor
    BMVS 5624: Molecular Virology    , 2008-present
    Virginia-Maryland College of Veterinary Medicine
    Four lectures: Dissemination, Virulence, and Epidemiology; Host Defense Mechanisms; Rotaviruses; Caliciviruses
  • Instructor
    BIOL 4734: Inflammation Biology, and BIOL 5734: Advanced Inflammation Biology     , 2011-present
    One lecture: Inflammation, Infection and Vaccination OR Vaccine Immunology
  • Instructor
    TBMH 5054: Immunity and Infectious Disease    , 2015-present
    Virginia-Maryland College of Veterinary Medicine
    One lecture: Vaccine Development
  • Course leader
    VM 8984, 90920, 201809: Emerging Infectious Diseases    , 2018-present
    Virginia-Maryland College of Veterinary Medicine
    Three lectures: Introduction: Definition of Emerging Infectious Disease and their Patterns; Emerging Caliciviruses and Enteroviruses; Emerging Coronaviruses: SARS, MERS, PEDV

Lijuan Yuan, MS, PhD
Professor of Virology and Immunology
Department of Biomedical Sciences and Pathobiology
Email: lyuan@vt.edu
Dr. Yuan's photography→

Casey L. Hensley
PhD student, August 2019–present
Email: lhcasey@vt.edu
Education:
BS, Eastern Mennonite University, Virginia
AAS, Veterinary Technology, Blue Ridge Community College, Virginia

Brian King, BS
Laboratory and research specialist, June 2023-present
Email: brian24@vt.edu
Education:
BS, Biochemistry, Virginia Tech, Virginia
BS, Clinical Neuroscience, Virginia Tech, Virginia

Lauren Lavoie, BS
Gnotobiotic Technician, January 2023-present
Email: laurenml23@vt.edu
Education:
BS, Animal Science, University of Connecticut

Charlotte Nyblade
PhD/DVM student, August 2021-present
Email: charlottejn@vt.edu
Education:
BS, Health and Human Biology, Brown University, Rhode Island

Viviana Parreno
Research scientist, July 2021-present
Email: vparreno2021@vt.edu
Education:
PhD, Veterinary Virology and Immunology, School of Veterinary Science, University of Buenos Aires, Argentina
MS, Statistic and Biometrics, School of Agronomic Science, Buenos Aires University, Argentina

Eric Truong, BS
Laboratory and research specialist, June 2023-present
Email: erictruong671@vt.edu
Education:
BS, Biochemistry, Virginia Tech, Virginia

Peng Zhou
Laboratory and research specialist, May 2019-present
Email: pengz81@vt.edu
Education:
PhD, Preventive Veterinary Medicine, South China Agricultural University, Guangzhou, China
MS, Clinical Veterinary Medicine, Southwest China University, Chongqing, China
BS, Veterinary Medicine, Southwest China University, Chongqing, China

  • Muqun Bai
    Visiting scholar (supported by Lanzhou Institute of Biological Products, China)
    2011-2012
  • Tammy (Bui) Castellucci
    PhD/DVM dual degree student
    2008-August 2017
  • Anna Fantasiz-Davis
    Laboratory and research specialist
    January 2022-December 2022
  • Christine Flora
    Virginia Governor’s School student
    Fall 2016-Spring 2017
  • Annie Frazier
    Laboratory and research specialist
    January 2022-May 2023
  • Maggie Frazier
    Laboratory and research specialist
    January 2022-May 2023
  • Ernawati Arifin Giri-Rachman
    Fulbright Visiting Scholar
    2012-2013
  • Sherif Ibrahim
    Post-doctoral visiting scholar (supported by US-Egypt Joint Board on Scientific and Technological Cooperation)
    2010-2011
  • Jiqiang Jing
    Visiting scholar (supported by Education Department, Shandong Province, China)
    2011
  • Jacob Kocher
    PhD student
    2009-November 2014
    Post-doctoral fellow at The University of North Carolina at Chapel Hill, December 2014
  • Jacqueline Lamar
    VT Post-baccalaureate Research and Education Program (VT-PREP) scholar
    2011-2012
  • Shaohua Lei
    PhD student
    August 2013-May 2018
    Post-doctoral associate and lab manager
    July-October 2018
    Currently a postdoctoral research fellow at St. Jude's Children's Research Hospital, Memphis, TN
  • Guanhong Li
    Visiting professor
    2014-2015
  • Guohua Li
    Research scientist
    2007-2015
  • Yanru Li
    Post-doctoral visiting scholar (supported by China Scholarship Council)
    2009-2010
  • Lin Lin
    PhD student
    2010-2011
    Transfered to The University of North Carolina at Chapel Hill Graduate School
  • Fangning Liu
    Visiting PhD student
    November 2007-November 2009
    Post-doctoral research associate
    2010-2012
  • Hassan M. Mahsoub
    Postdoctoral associate
    September 2019–December 2020
  • Jiangdi Mao
    Visiting MS student
    MS, Animal Nutrition and Feeding, Zhejiang A&F University, China
    June 2018-June 2019
  • Ashwin Ramech
    PhD student
    July 2014–May 2020
  • Shujing Rao
    Research scientist
    2009-2011
  • Helen Samuel
    Undergraduate student
    2015-2017
  • Sofia Schnur
    Research assistant
    September 2020-October 2021
  • Hong Tian
    Post-doctoral visiting scholar
    2014-2015
  • Christine Tin
    Undergraduate student
    2012-2016
  • Erica Twitchell
    T32 PhD student
    August 2014-November 2018
  • Haifeng Wang
    Post-doctoral visiting scholar
    2012-2013
  • Mariah Weiss
    Laboratory and research specialist, lab manager
    2013-2016
  • Ke Wen
    PhD student
    2007-2011
    Post-doctoral research associate
    2011-2015
  • Xingdong Yang
    PhD student
    2010-2015
  • Alice Leruth, Biological Sciences, Virginia Tech, September 2022-present
  • Nicole Weddington, Biological Sciences with a minor in Animal and Poultry Sciences, Virginia Tech, August 2022-present
  • Ruiqing Cai, Major in chemistry and minor in public health, Virginia Tech, Feb. 2022-Dec. 2022
  • Sarah Garrison, Biological Sciences, Virginia Tech, Nov. 2021-May2023
  • Annie Frazier, Biological Sciences, Virginia Tech, Jan. 2021-Dec. 2021
  • Maggie Frazier, Clinical Neuroscience, Virginia Tech, Jan. 2021-Dec. 2021
  • Kelsey Kiley, Biological Sciences, Virginia Tech, Jan. 2021-Dec. 2021
  • Rachel Cropp, Animal and Poultry Sciences Pre-Vet, Virginia Tech, 2018-2019
  • Caroline Swarm, Animal and Poultry Sciences Pre-Vet, Virginia Tech, 2018-2019
  • Helen Samuel, Biological Sciences, Virginia Tech, 2015-2017
  • Christine Tin, Biological Sciences, Virginia Tech, 2012-2016
  • Emily Murray, BS, Biology and Animal and Poultry Sciences, Virginia Tech, volunteer, 2011
  • Dehai Deng, BS, MD, volunteer, 2010
  • Hui Deng, BS, PhD, volunteer, 2010
  • Marjory Jones, Biology and Psychology, Virginia Tech, 2010
  • Richard Kevorkian, Microbiology, Virginia Tech, 2010
  • Dorothy 'Nezzie' Jones, DVM candidate, SVSRP participant, VA-MD College of Veterinary Medicine, 2009-2010
  • Feng Li, BS, MS, volunteer, 2009-2010
  • Baowei Meng, Biological Sciences, Virginia Tech, 2009-2010
  • Rachael Dunn, Animal and Poultry Sciences, Virginia Tech, MAOP summer student, 2009
  • Ruth E. Johnson, Biology and Equine Management, Asbury University, 2009
  • Kelly Stoneburner, Biochemistry, Virginia Tech, 2009
  • Christina ‘Nina’ Tisdale, Microbiology, Virginia Tech, 2008
  • Yuan Lab’s project on evaluating a novel norovirus vaccine featured (Virginia Tech News, July 2022)
  • Lijuan Yuan was awarded the Grant Turnwald Innovation Award for 2020-2021 (Virginia Tech News, July 2022)
  • Lijuan Yuan's norovirus research highlighted (Research Features, December 2021)
  • Lijuan Yuan featured for using gnotobiotic piglets to study rotavirus (LabAnimal, September 2019)
  • Virginia Governor’s School student Christine Flora’s research project in the Yuan Lab titled “Assessing Rice Bran’s Protective Efficacy Against Porcine Rotavirus Infection in IPEC-J2 Cells” received three blue ribbons and won Flora a trip to the International Science and Engineering Fair, Los Angeles, May 2017. (The Roanoke Times)
  • Lijuan Yuan was among 15 of the world's leading rotavirus researchers invitedto give a talk at the "Symposium on Rotavirus Human Immunology: Advancing Science, Decreasing Disease" at the University of Vermont Vaccine Testing Center, Burlington, Vermont, May 15-16, 2017. Yuan's talk was titled "The role of T cells in rotavirus inducted protective immunity: Lessons from a gnotobiotic pig model of human rotavirus diarrhea." (University of Vermont News, PDF)
  • Lijuan Yuan won an inaugural 2016-2017 Outstanding Graduate Mentor Award from the Virginia Tech Graduate School. Professors from each college were nominated by graduate students and faculty across the university. (Virginia Tech News)
  • Graduate student Shaohua Lei of the Yuan Lab won the 2016-2017 Outstanding Doctoral Student Award from the Virginia Tech Graduate School. (VA-MD Vet Med news)
  • Lijuan Yuan gains rotavirus research experience during sabbatical in Australia. (VA-MD Vet Med news)
  • Lijuan Yuan won the Grand Challenges Explorations Round 12 grant for research in global health and development from the Bill and Melinda Gates Foundation. (Global Grand Challenges news and Virginia Tech News)
  • Graduate students Ashwin Ramesh and Erica Twitchell of the Yuan Lab won Outstanding Ph.D. Student Poster awards at the 27th Annual Research Symposium, March 2016, Virginia-Maryland College of Veterinary Medicine. (VA-MD Vet Med news)
  • Undergraduate student Christine Tin of the Yuan Lab was among three Virginia Tech students awarded a Barry M. Goldwater Scholarship for the 2015-16 academic year. (Virginia Tech News)
  • Christine Tin, an undergraduate student in the Yuan Lab, was among three students to present their work at the 2014 National Conference on Undergraduate Research. (Virginia Tech News)
  • Yuan Lab hosts Fulbright Scholar Ernawati Giri Rachman from the Bandung Institute of Technology, Indonesia. (Fulbright News)
  • Lijuan Yuan was honored with the Pfizer Award at VA-MD Vet Med's 2011 Research Symposium. (Virginia Tech News)
  • Lijuan Yuan was hired in 2007 as assistant professor of virology at Virginia Tech as part of the cluster hires supporting the host-pathogen-environment interaction (HPEI) research focus. (Virginia Tech News)