By Patrick Wascovich

Dr. Lora Hooper, whose discoveries have helped explain how beneficial bacteria can safely exist in the intestinal tract and may ultimately reveal what to do when illness-causing bacteria predominate, has been named first holder of the Jonathan W. Uhr, M.D. Distinguished Chair in Immunology.

Dr. Lora Hooper

A Professor of Immunology and Microbiology at UT Southwestern Medical Center who also holds an appointment in the Center for Genetics of Host Defense, Dr. Hooper said she was touched by having been selected to hold the Uhr Distinguished Chair, named in honor of an internationally recognized researcher, educator, and mentor who served at UT Southwestern for 39 years – including 25 years as Chairman of Microbiology – before being named Professor Emeritus in 2011.

“I am tremendously honored to have been selected as the first holder of the Uhr Distinguished Chair in Immunology,” Dr. Hooper said. “Dr. Uhr is the embodiment of the spirit of collaboration and standard of scientific excellence that have made the UT Southwestern Department of Immunology an ideal setting for my research program for over a decade. I am deeply grateful to receive this recognition and support.”

Dr. Ellen Vitetta, Professor of Immunology and Microbiology who chaired the Uhr Distinguished Chair committee, said, “On behalf of the committee we are all thrilled that Lora will hold the Uhr Chair. She embodies all the qualities that Jonathan felt were important in an outstanding scientist and educator. She will be a leader in the next generation of immunologists.”

Though people and other mammals mostly enjoy a mutually beneficial relationship with our indigenous bacteria, very little is understood about how such host-bacterial relationships are set up and maintained, or how these resident gut microbes communicate with our own cells.

Deciphering that complex relationship is the ultimate goal of Dr. Hooper and her team of researchers. Dr. Hooper’s work focuses on understanding how the staggeringly dense and complex community of intestinal microbes avoids triggering infections. She is specifically interested in how the lining of the gut, called the epithelium, prevents bacteria from escaping the intestinal tract and wreaking havoc in other parts of the body. The battles that take place, or don’t, in a sort of “demilitarized zone” in the intestine dominate her studies. That zone is a 50-micron-wide area – about half the width of a human hair – between the intestinal wall and the normally good, or commensal, bacteria that live in the gut. Under normal conditions, these bacteria aid in digestion and the delivery of nutrients from the food we eat without damaging the delicate intestinal lining. When something goes wrong with this arrangement the bacteria are able to invade the intestinal wall and can cause inflammatory bowel disorders.

To study this process, her laboratory has established a germ-free colony where mice are raised under complexly sterile conditions inside plastic isolators. The colony is one of a handful of such facilities in the U.S.

“By comparing intestinal immune cells from germ-free mice with those from normal, non-sterile mice, we can determine how indigenous gut bacteria influence the development and function of the immune system,” Dr. Hooper said.

Recruited to UT Southwestern in 2003, Dr. Hooper has led investigations that have significant recognition. One of the most recent came in 2012, when the Academy of Medicine, Engineering, and Science of Texas selected her as the Edith and Peter O’Donnell Award in Medicine recipient.

As an Assistant Professor, Dr. Hooper was the Nancy Cain and Jeffrey A. Marcus Scholar in Medical Research, in Honor of Dr. Bill S. Vowell. By May 2008, her scientific discoveries had resulted in her being selected as a Howard Hughes Medical Institute Investigator at UT Southwestern.

Her studies in germ-free mice have already led to the discovery of a family of secreted C-type lectins that are key members of the gut’s arsenal of antimicrobial proteins. Dr. Hooper’s research group showed that when a microbe comes into contact with the intestinal lining, the epithelial cells produce proteins that kill the bacteria, preventing them from crossing the epithelial wall and invading deeper tissues.

In 2011, Dr. Hooper published a study in the journal Science showing for the first time how a protein that her laboratory discovered in 2006 works to police the intestinal demilitarized zone and keep bacteria from damaging the intestinal lining. In a study published in the Proceedings of the National Academy of Sciences in October 2012, her laboratory found that gut bacteria launch biological warfare against other bacterial species in response to environmental stress, such as changes in available nutrients or the presence of antibiotics. The bacteria go to war by churning out viruses that attack other bacterial species. The scientists hope to harness this intestinal warfare to develop ways to fight antibiotic-resistant bacterial infections.

Dr. Hooper received a doctorate in molecular cell biology and biochemistry from Washington University in St. Louis, where she also completed a postdoctoral fellowship.

Dr. Uhr, one of UT Southwestern’s most distinguished and revered scientists and academic leaders, came to Texas in 1972 when Dr. Donald Seldin, then Chairman of Internal Medicine, recruited him to lead the medical center’s Department of Microbiology. By all objective criteria the department became one of the best  in the world.

A member of the National Academy of Sciences (NAS), the Institute of Medicine (IOM), the American Academy of Arts and Sciences (AAAS), and past president of the American Association of Immunologists (AAI), Dr. Uhr stepped down as Chairman of Microbiology in 1997 to join the Cancer Immunobiology Center, directed by one of his most accomplished recruits, Dr. Vitetta. Elected to the Texas Women’s Hall of Fame in 2006, Dr. Vitetta is also a member of the NAS, IOM, and a past president of the AAI.

“Jonathan was  an outstanding scientist, teacher, mentor, and leader,” said Dr. Vitetta. “As department Chairman, he had extremely high standards, and took an interest in each and every faculty member. He read and critiqued grants and papers. He rehearsed our lectures. He gave sage advice about everything and anything. He also believed in collegiality and fun and loved to see his faculty having a good time at various department functions.”

An internationally recognized biomedical researcher, Dr. Uhr has been at the forefront of many seminal discoveries in immunology. He first demonstrated the role of passive antibody feedback, a body of work that led to the prevention of Rh disease. He discovered how antibodies were made inside the  plasma cell. He and Dr. Vitetta discovered and described the antigen specific receptors on B cells, opened the field of tumor dormancy, and developed  immunotoxins to target cancer cells both in mice and humans. In the last two decades of his career he pioneered  the  investigation of dormant cancer cells and identified  circulating tumor cells (CTCs), which are shed from primary tumors. A commercial test to detect CTCs in the human bloodstream, based on Dr. Uhr’s patent, is now used routinely in clinical laboratories to monitor cancer therapy  Although retired, he continues to work with colleagues to combine that technique with advanced imaging technology to characterize captured cancer cells, which could improve diagnosis, monitoring, and treatment of the disease.

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Dr. Seldin, Chairman Emeritus and UT System Professor of Internal Medicine, holds the William Buchanan Chair in Internal Medicine. He has been elected to the NAS, IOM, and the AAAS.

Dr. Vitetta holds the Scheryle Simmons Patigian Distinguished Chair in Cancer Immunobiology, and a distinguished Teaching Chair.