Herpes simplex virus entry mechanisms; vaccinia virus entry and the proteins involved in protection.
Key words: herpes, HSV, virology, glycoproteins, virus entry, vaccinia virus, vaccines.
Description of Research
The research in my laboratory is conducted in collaboration with Dr. Gary H. Cohen of the School of Dental Medicine, UPenn. Our longterm goal is to understand molecular events that mediate virus entry into susceptible cells and promote the pathogenesis of the virus in its human host.
Research on herpes simplex virus (HSV):
Four viral glycoproteins, gB, gD, gH and gL are essential for virus entry and spread. HSV entry is mediated by one of several different receptors. including HVEM (HveA) a TNF receptor, and nectin-1, a cell adhesion molecule that is a member of the Ig superfamily. We showed that purified gD interacts directly with purified HVEM and nectin-1 using such techniques as co-precipitation,
ELISA and biosensor. In collaboration with two crystallographers, Andrea Carfi, now at Novartis and Ekaterina Heldwein, now at Tufts University, we have solved the structures of all of the “players” in HSV entry, including gD bound to HVEM, gD bound to nectin-1, gB and gH/gL. These structures, in conjunction with our ongoing efforts to understand the relationship between structure and function have led us to propose that HSV entry follows a pathway that begins with binding of gD to one of its two receptors. This interaction leads to a conformational change to gD that activates it so that it signals to gH/gL, the regulator of fusion, which is then carried out by gB. Of particular interest is the fact that both gH/gL and gB are highly conserved among all herpesviruses, including the plethora of animal herpesviruses that cause serious diseases of both companion animals and farm and zoo animals. Thus our work has direct relevance to veterinary medicine. It also has relevance to human medicine as there are at least eight human herpesviruses, several of which cause serious diseases such as chicken pox, shingles, lymphomas to name just a few. Our work continues to focus on the mechanisms that regulate the entry pathway.
Another aspect of our work is to focus on poxviruses such as variola (smallpox) and vaccinia (the virus used as a vaccine against smallpox). We are using similar techniques to those above to study the envelope proteins of vaccinia virus (VV). Our two goals are to understand the very complex entry process as well as to develop subunit vaccines that could be used to augment the live virus anti-smallpox vaccine currently used for vaccinating members of the armed forces. This vaccine, though it has been effective enough to eradicate smallpox worldwide is not without serious side effects and cannot be used in immunocompromised or pregnant individuals. Currently, we are focusing on a key entry protein, L1 , for which we have evidence is the receptor binding protein for vaccinia. We have proposed a novel model for how L1 works. This is called the myristoyl switch model, a way that L1 undergoes a conformational change that triggers the entry-fusion complex to carry out fusion.
Foo C H et al. J. Virol. 2012;86:5437-5451. Myristoyl switch model for L1 function
A very similar protein is present in most orthopox virusesThe proteins and antibodies we have developed have been evaluated alone and in combination as protective reagents in both mouse and monkey models
student will use the materials at hand to master the technique and apply it to new questions concerning virus entry, receptor down regulation and events that focus on glycoproteins during viral replication.
Tina Cairns, Ph.D., Senior Research Scientist
John Gallagher, Ph.D., Postdoctoral Scientist
J. Charles Whitbeck, Ph.D., Senior Research Scientist
Doina Atanasiu, Senior Research Scientist
Huan Lou, BS, Research Specialist
Manuel Ponce de Leon, MS, Research Specialist
Chwan Hong Foo, Postdoctoral Scientist
Spencer Shelley, Predoctoral Student (combined degree VMD/PhD)
Former graduate students:
J.T. Matthews, Ph.D. Senior Scientist, Aventis Pharmaceuticals
C. Seidel-Dugan, Ph.D. Senior Scientist, Elixis Pharmaceuticals
D. L. Sodora, , Ph.D., Associate Professor, University of Texas
Shan-Ling Hung, Ph.D. May, 1992; Professor of Oral Biology, National Yang-Ming University, Taipei, Taiwan R.O.C.
Deborah Long,, Ph.D. Aug., 1992. Group Leader, Virology program, Wyeth, Inc
Hsien-Yuan Chiang, Ph.D. Professor of Microbiology, National Defense Medical Center Taipei, Taiwan
Ruth Tal-Singer, Ph.D., Section Chief, Smith-Kline Beecham
Christopher Handler, Ph.D. CRA, Quintiles, Rockville, MD
Anthony Nicola, Ph.D., Assistant Professor, Virginia Commenwealth University
Tao Peng, Ph.D. (Biology Grad. Group) Staff Scientist, Immusol
Sarah Connolly, Ph.D.. Post-doctoral fellow, Dr. Robert Lamb, Northwestern University.
Eric Lazear, PhD 2008, Post-doctoral fellow at Washington University
Brian Hannah, PhD 2008, US Army, Fort Dietrich,
Katie Stiles, PhD 2010, Post-doctoral fellow with Margaret Kielian, Einsteing Medical School,
Chwang Hong Foo, PhD 2011, Post-doctoral fellow in our laboratory
Heldwein, Ekaterina E. Lou, Huan. Bender, Florent C. Cohen, Gary H. Eisenberg, Roselyn J. Harrison, Stephen C. Crystal structure of glycoprotein B from herpes simplex virus 1. Science 313: 217-20, 2006.Xiao, Yuhong. Aldaz-Carroll, Lydia. Ortiz, Alexandra M. Whitbeck, J Charles. Alexander, Edward. Lou, Huan. Davis, Heather L. Braciale, Thomas J. Eisenberg, Roselyn J. Cohen, Gary H. Isaacs, Stuart N. A protein-based smallpox vaccine protects mice from vaccinia and ectromelia virus challenges when given as a prime and single boost. Vaccine 25: 1214-24, 2007.Atanasiu D, Whitbeck JC, Cairns TM, Reilly B, Cohen GH and Eisenberg RJ. Bimolecular complementation reveals that glycoproteins gB and gH/gL of herpes simplex virus interact with each other during cell fusion. Proc. Nat’l Acad Sci USA : , 2007.Foo Chwan Hong, Lou Huan, Whitbeck J Charles, Ponce-de-León Manuel, Atanasiu Doina, Eisenberg Roselyn J, Cohen Gary H Vaccinia virus L1 binds to cell surfaces and blocks virus entry independently of glycosaminoglycans. Virology 385: 368-82, 2009.Hannah Brian P, Cairns Tina M, Bender Florent C, Whitbeck J Charles, Lou Huan, Eisenberg Roselyn J, Cohen Gary H Herpes simplex virus glycoprotein B associates with target membranes via its fusion loops. Journal of virology 83: 6825-36, 2009.Wright Catherine C, Wisner Todd W, Hannah Brian P, Eisenberg Roselyn J, Cohen Gary H, Johnson David C Fusion between perinuclear virions and the outer nuclear membrane requires the fusogenic activity of herpes simplex virus gB. Journal of virology 83: 11847-56, 2009.Atanasiu Doina, Whitbeck J Charles, de Leon Manuel Ponce, Lou Huan, Hannah Brian P, Cohen Gary H, Eisenberg Roselyn J Bimolecular complementation defines functional regions of Herpes simplex virus gB that are involved with gH/gL as a necessary step leading to cell fusion. Journal of virology 84: 3825-34, 2010.Chowdary Tirumala K, Cairns Tina M, Atanasiu Doina, Cohen Gary H, Eisenberg Roselyn J, Heldwein Ekaterina E Crystal structure of the conserved herpesvirus fusion regulator complex gH-gL. Nature structural & molecular biology 17: 882-8, 2010.Stiles Katie M, Whitbeck J Charles, Lou Huan, Cohen Gary H, Eisenberg Roselyn J, Krummenacher Claude Herpes simplex virus glycoprotein D interferes with binding of herpesvirus entry mediator to its ligands through downregulation and direct competition. Journal of virology 84: 11646-60, 2010.Foo Chwan Hong, Whitbeck J Charles, Ponce-de-León Manuel, Saw Wan Ting, Cohen Gary H, Eisenberg Roselyn J The myristate moiety and amino terminus of vaccinia virus l1 constitute a bipartite functional region needed for entry. Journal of virology 86: 5437-51, 2012.Lazear Eric, Whitbeck J Charles, Ponce-de-Leon Manuel, Cairns Tina M, Willis Sharon H, Zuo Yi, Krummenacher Claude, Cohen Gary H, Eisenberg Roselyn J Antibody-induced conformational changes in herpes simplex virus glycoprotein gD reveal new targets for virus neutralization. Journal of virology 86: 1563-76, 2012.Cairns Tina M, Whitbeck J Charles, Lou Huan, Heldwein Ekaterina E, Chowdary Tirumala K, Eisenberg Roselyn J, Cohen Gary H Capturing the herpes simplex virus core fusion complex (gB-gH/gL) in an acidic environment. Journal of virology 85: 6175-84, 2011.Atanasiu Doina, Saw Wan Ting, Cohen Gary H, Eisenberg Roselyn J Cascade of events governing cell-cell fusion induced by herpes simplex virus glycoproteins gD, gH/gL, and gB. Journal of virology 84: 12292-9, 2010.