Robert V. Schoborg, Ph.D.
Department of Biomedical Sciences
Current Research Projects:
My Ph.D. and post-doctoral training was in the molecular and cellular biology of murine parvoviruses and ovine lentiviruses, respectively. However, my laboratory is now focused on sexually transmitted diseases of humans. Because sexually transmitted diseases cause enormous morbidity and mortality world wide, these studies have the potential to significantly impact human health. Our overall goal is to understand how the sexually transmitted bacterium, Chlamydia trachomatis, interacts with the host to produce disease. C. trachomatis is an obligate intracellular, Gram negative bacterium with a complex developmental cycle (Fig. 1). Genital
infections are very common in the US
, with greater than 2,800,000 new cases being reported each year. Chlamydial infection is often inapparent and can persist for years, causing diseases ranging from mild inflammation to infertility or life-threatening ectopic pregnancy. It is our hope that a better understanding of chlamydial pathogenesis will ultimately lead to the development of more effective therapies and preventative interventions.
We currently have three specific research projects ongoing in our laboratory. The first project is entitled “Defining the relationship between chlamydial infection and cervical cancer” (previously funded by NIAID R15 AI078373-01A1 1/15/09-1/14/12). In this project, we are testing the following two hypotheses: i) that chlamydial infection increases the nuclear DNA mutation frequency within human cells; and ii) that chlamydial infection alters expression or activity of host DNA repair and DNA damage checkpoint proteins. We have recently demonstrated that: i) chlamydial infection increases host cell mutation by 3 fold; and ii) these mutations are fixed in the host genome if the infection is cured by exposure to antimicrobials. We have also observed redistribution of host DNA repair proteins to the nucleus in C. trachomatis-infected cells, which is an indirect indicator of increased host DNA damage (Fig. 2). We are currently evaluating host mutation frequency in C. muridarum vaginally-infected mice. We predict that these data will significantly impact both cervical cancer prevention and risk assessment.
In the second project (“Development of an animal model of chlamydial persistence”; NIAID R21 AI082322-01; 06/01/09-05/31/12), we are testing the following two hypotheses: i) amoxicillin-exposed, persistent chlamydiae can induce alterations in murine host cell gene expression; and ii) amoxicillin-exposure can induce persistent (i.e. viable but non-infectious) chlamydial infection in vivo. In the course of these studies, we have: i) definitively demonstrated that viable but non-infectious chlamydial forms are present in vivo under appropriate conditions; and ii) developed the first experimentally tractable animal model of chlamydial persistence. This unique model will ultimately facilitate exploration of how persistent infection impacts chlamydial pathogenesis, transmission and antimicrobial therapy. The third project (“Characterization of a novel host pathway that regulates chlamydial development”) was previously supported by NIH/NIAID R21AI59563 and is now supported by NIH/NIAID R01 AI095637-01. Previously published data from our laboratory demonstrate that HSV-2 super-infection of C. trachomatis-infected, human genital epithelial cells profoundly alters chlamydial development.In this model, HSV attachment to the host cell surface protein nectin-1 appears to initiate a novel host cellular anti-bacterial response that restricts chlamydial development. We are currently characterizing this novel anti-chlamydial host response using phosphoprotein microarray and kinase inhibitor analyses as well as studying the progression of genital tract disease in vaginally-infected nectin-1 knock-out mice. Given that C. trachomatis/HSV co-infections are common and that the consequences of such co-infections are unstudied, our studies will reveal new and interesting facets of HSV/chlamydia co-pathogenesis and will hasten development of in vivo models of polymicrobial sexually transmitted infections.
As basic medical sciences educators, we have four tasks. First, we must decide what, from the immense medical/research literature, to teach. Second, we have to present course material in such a way that the majority of our students can comprehend it. Third, we must evaluate how well the students have mastered the subject. Fourth, we must motivate our students to learn the material. All four tasks are difficult and must be mastered if one is to be an effective educator. Basic scientists tend to be most comfortable with those tasks that are quantifiable. Thus, motivation, a fuzzy subject at best, is usually left up to the students and is addressed, at most, by giving a course grade. In my opinion, the issue of motivation is paramount. Motivated students will ALWAYS accomplish more than those that are unmotivated, regardless of other factors. Although we have little ability to determine why our students decided to become physicians or scientists, we can substantially influence their motivation once they enter our medical and graduate programs. So, once they are here, how do we help keep them motivated? Though professional expectations and grades play a role, I would suggest that an often overlooked requirement is respect. If a faculty member puts effort into their teaching, most students will respect them for it. Such respect provides the students with additional motivation; making them more likely to listen, work hard and perform. Such respect is not given freely, it is earned by the efforts an instructor makes on behalf their students. I honestly feel that, because it is my job, I have a responsibility to my students and to the people of Tennessee to teach to the best of my ability. This means that if I do not currently have all the necessary skills, it is my responsibility to acquire them - a task that I take very seriously.
I have always considered direction of student research projects and service on student advisory committees to be a critical component of my position in the College of Medicine. One of the most important considerations in designing a student research project is that it must provide a complete, well‑rounded scientific education. All of my students engage in projects that require a wide range of knowledge and experimental approaches/techniques. These projects encourage the student to: i) become proficient in many different experimental approaches, ii) develop independence and tenacity, iii) develop the ability to properly design and trouble‑shoot experiments, iv) learn how to "ask the right questions" and v) stay current in the scientific literature. These abilities will allow students to successfully compete for jobs and develop independent careers.
Former and Current Students:
Lillia Holmes, M.S., 1997.
Michelle Abelson, M.S., 1998.
Michelle Abelson, Ph.D., 2000.
Bridget Graves, M.S., 2001.
Srilekha (Rinti) Deka, Ph.D., 2005.
Jennifer Vanover, Ph.D., 2008.
Jingru Sun, Ph.D., 2009.
Reginia Phillips-Campbell, current Ph.D. student.
Jessica Slade, current Ph.D. student.
Elizabeth Hanson, B.S., 2001.
Sarah Mullins, B.S., 2009.
Matt Novak, B.S., 2012.
McNair Undergraduate Program Research Students:
Nicole Mikel, 1996.
Eric Donald, 1997.
Chris Daniels, 2008-9.
Medical Student Summer Research Fellows:
Ritu Khanna, COM Class of 2005.
Dawn Lajoie, COM Class of 2006.
Scott Embry, COM Class of 2010.
Courtney Childress, COM Class of 2014.
Student Honors and Awards (since 2001):
1. Elizabeth Hansen (Undergraduate Honors student). Award: 1st place, Undergraduate Division, 17th Annual ETSU Student Research Forum, April 2001.
2. Srilekha Deka (Ph.D. student). Awards: i) 1st place, Graduate I Division, 18th Annual ETSU Student Research Forum, April 2002; ii) 3rd place, Microbiology Division, Annual Meeting of the Tennessee Academy of Sciences, Nov. 2002; iii) 1st place, Graduate II Division, 19th Annual ETSU Student Research Forum, April 2003; iv) American Society of Microbiology Travel Grant, May 2003; v) Chlamydia Basic Research Society Travel Grant, March 2005; and vi) ETSU School of Graduate Studies Outstanding Dissertation Award, May 2006.
3. Jingru Sun (Ph.D. student). Awards: i) 1st place, Graduate I Division, 22nd Annual ETSU Student Research Forum, April 2006; ii) ETSU School of Graduate Studies Research Grant, 2006; and iii) ETSU School of Graduate Studies Outstanding Dissertation Award, May 2010.
4. Jennifer Vanover (Ph.D. student). Awards: i) ETSU School of Graduate Studies Research Grant, 2005; ii) Chlamydia Basic Research Society Travel Grant, March 2005; iii) Jane E. Raulston memorial graduate student presentation award, Third International Meeting of the Chlamydia Basic Science Research Society, Louisville, KY, March 2007; iv) 2nd place, Graduate II Division and 1st place, student choice award, 23rd Annual ETSU Student Research Forum, March 2007; and v) ETSU School of Graduate Studies Outstanding Dissertation Award, May 2009.
5. Chris Daniels (Undergraduate McNair student). Awards: i) 2nd place, Undergraduate Division, 25th Annual ETSU Student Research Forum, April 2009; and ii) 1st place, McNair Scholar Division, 25th Annual ETSU Student Research Forum, April 2009.
6. Regenia Phillips-Campbell (Ph.D. student). Awarded ETSU School of Graduate Studies Research Grant, 2011.
7. Matthew Novak (Undergraduate student). Awarded 2nd place, Undergraduate Division, 28th Annual ETSU Student Research Forum, April 2012.
I am a firm believer in the adage “work hard and play hard”. Most of my “out of work” activities are of the athletic variety and include backpacking, canoeing, kayaking, camping, fishing and wildlife photography.