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School of Medicine
Kenneth Whitaker Witwer, Ph.D.
Assistant Professor of Molecular and Comparative Pathobiology
Research Interests: microRNA; RNA interference; extracellular vesicles; exosomes; retrovirology; genome editing; HIV/AIDS; immunology
Dr. Kenneth W. Witwer is an assistant professor of molecular and comparative pathobiology at the Johns Hopkins University School of Medicine. His research focuses on extracellular vesicles, RNA-mediated regulation, biomarker discovery, and therapeutic modulation of innate and intrinsic defenses.
He received his undergraduate degree from Penn State University, where he studied biochemistry and molecular biology, German, and international politics. He earned a doctorate from the Biochemistry, Cellular and Molecular Biology Program at Johns Hopkins and received a National Science Foundation Graduate Research Fellowship. Dr. Witwer remained at Johns Hopkins to complete a postdoctoral fellowship in microRNA biomarker research, and he joined the faculty in 2011.
- Assistant Professor of Molecular and Comparative Pathobiology
- Assistant Professor of Neurology
- B.A., Pennsylvania State University (Pennsylvania) (1999)
- Ph.D., Johns Hopkins University School of Medicine (Maryland) (2010)
Johns Hopkins University School of Medicine, Baltimore, MD, 2011, Molecular and Comparative Pathobiology
Research & Publications
Dr. Witwer investigates extracellular vesicles and RNA in human disease, including HIV infection and inflammatory disease. Ribonucleic acid (RNA) molecules are found not only inside, but also outside of human cells in biological fluids such as blood plasma, urine, and cerebrospinal fluid. Although quite labile, these molecules are protected from degradation by molecular shuttles including extracellular vesicles (EV). Rapidly expanding research programs over the last several years indicate that EVs and their nucleic acid cargo may provide early warning of disease, contribute to the defense against disease, and serve as models for effective therapies. Dr. Witwer is also interested in extracellular RNA as a potential therapeutic approach.
- "Extracellular Vesicle-Mediated Immunomodulation in HIV Infection and Nicotine Abuse"
- "Development of miRNA-based therapies to silence or purge the latent macrophage reservoir in HAND"
- "Biomarkers of the HIV-associated neurocognitive disorders: plasma and CSF miRNAs in prediction, diagnosis and pathogenesis of HAND" (in collaboration with Dr. Janice Clements)
- "Circulating cellular and extracellular noncoding RNAs in HIV-1 Elite Suppression" (in collaboration with Dr. Joel Blankson).
Rotation projects are available to Cellular and Molecular Medicine students. Local undergraduates with laboratory experience and a strong interest in HIV, RNA, or extracellular vesicle research are encouraged to inquire about available projects. Undergraduates in the Witwer lab have co-authored numerous publications and have earned:
- Four young investigator awards from professional meetings;
- One Dean's Undergraduate Research Award (DURA);
- Five Provost's Undergraduate Research Awards (PURA);
- Four Center for AIDS Research Baltimore HIV Scholars; and
- A Second Decade Society scholarship.
Lab Website: Ken Witwer Laboratory
Technology Expertise KeywordsmiRNA, genome editing, ultracentrifugation, microarray, RNA-seq, in situ hybridization, molecular biology, immunofluorescence, immunohistochemistry
Selected PublicationsView all on Pubmed
EV-TRACK Consortium, Van Deun J, Mestdagh P, et al. EV-TRACK: transparent reporting and centralizing knowledge in extracellular vesicle research. Nature Methods 2017.
Han PA, Kim HS, Cho S, Fazeli R, Najafian A, Khawaja H, McAlexander M, Dy B, Sorensen M, Aronova A, Sebo TJ, Giordano TJ, Fahey TJ 3rd, Thompson GB, Gauger PG, Somervell H, Bishop JA, Eshleman JR, Schneider EB, Witwer KW, Umbricht CB, Zeiger MA. Association of BRAF V600E Mutation and MicroRNA Expression with Central Lymph Node Metastases in Papillary Thyroid Cancer: A Prospective Study from Four Endocrine Surgery Centers. Thyroid 2016.
Kim V, Mears B, Powell BH, Witwer KW. Mutant Cas9-transcriptional activator activates HIV-1 in the presence and absence of LTR-specific guide RNAs. Science Matters 2017.
Eitan E, Hutchison ER, Marosi K, Comotto J, Mustapic M, Nigam S, Suire C, Maharana C, Machairaki V, Witwer KW, Kapogiannis D, Koliatsos VE, Mattson MP. Extracellular Vesicle-Associated Aβ Mediates Trans-Neuronal Bioenergetic and Ca2+-Handling Deficits in Alzheimer's Disease Models. Nature Partner Journal Aging and Mechanisms of Disease 2016.
Buchanan EL, Espinoza DA, McAlexander MA, Myers SL, Moyer A, Witwer KW. SAMHD1 transcript upregulation during SIV infection of the central nervous system does not associate with reduced viral load. Scientific Reports 2016.
Academic Affiliations & Courses
Graduate Program Affiliation
Dr. Witwer is a faculty member of the Cellular and Molecular Medicine graduate program (http://cmm.jhmi.edu/).
Activities & Honors
- Young Investigator Award, 18th Conference on Retroviruses and Opportunistic Infections, 2011
- Richard T. Johnson Young Investigator Award, International Society for NeuroVirology, 2009
- Travel Grant, International Society for NeuroVirology, 2009
- Keystone Symposia Scholarship, Keystone Symposia, 2011
- Scholl Scholarship, Penn State University, 2001 - 2002
- Turock Young Scientist Award, Turock Family Foundation, 2002
- Center for AIDS Research Scholar Award, Johns Hopkins University , 2014
- Graduate Research Fellowship, National Science Foundation , 2003 - 2006
- International Society for Extracellular Vesicles, 2012
- International Society for NeuroVirology, 2009
- American Society for Exosomes and Microvesicles, 2012
- American Association for the Advancement of Science, 2002
- Secretary General, International Society for Extracellular Vesicles
- Associate Editor, Journal of Extracellular Vesicles
- Editorial Board Member, Clinical Chemistry (American Association for Clinical Chemistry)
- Co-Chair, 2018 Gordon Research Conference and Gordon Research Seminar on Extracellular Vesicles
- Chair, Local Organizing Committee, ISEV2015, International Society for Extracellular Vesicles
Coordinated the organization of an international meeting with >800 attendees in Bethesda, Maryland in April, 2015.
- Panelist, Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) Scientific Advisory Panel (SAP) on Human Health and Ecological Risk Assessments for SmartStax PRO, US Environmental Protection Agency
Minutes of this 2016 Scientific Advisory Panel can be found at: https://www.epa.gov/sites/production/files/2016-12/documents/rnai_sap_sept_2016_final_minutes.pdf
- Panelist, Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) Scientific Advisory Panel (SAP) on RNAi technology as a pesticide, US Environmental Protection Agency
Minutes of this 2014 Scientific Advisory Panel meeting can be found at http://www2.epa.gov/sites/production/files/2015-06/documents/012814minutes.pdf .
- Executive Committee Member-at-Large, International Society for Extracellular Vesicles
- Ad-hoc reviewer, More than 70 scientific journals
Videos & Media
Recent News Articles and Media Coverage
MicroRNA and Cancer Therapy. Science Friday, May, 2015.
The Retraction War. Jill Neimark, Aeon. December, 2014.
Fact or Artifact? Jef Akst, The Scientist. October, 2014.
HIV Denial: Alive and Well in 2014. Tara Smith, Aetiology. September, 2014.
A Lethal Dose of RNA. Kai Kupferschmidt, Science, August, 2013.
So Science...May have Gotten it Wrong. Now What? Virginia Hughes, National Geographic Phenomena. July, 2013.
U.S. Government Accuses Open Access Publisher of Trademark Infringement. Jocelyn Kaiser, ScienceInsider. May, 2013.
Kenneth Witwer on microRNA and cellular Bubbles. Fundamentals