UMMS Research and Graduate Studies

University of Michigan scientists have used gene therapy to grow new auditory hair cells in adult guinea pigs – a discovery that could lead to new treatments for human deafness and age-related hearing loss.
Healthy hair cells are vital to the ability to hear, but aging, infection, certain medications and exposure to loud noises can damage or destroy hair cells causing sensorineural hearing loss – a condition affecting over 30 million Americans. Since the discovery, in the late 1980s, that birds can spontaneously regenerate damaged hair cells, scientists have been trying to find a way to induce the replacement of lost hair cells in mammals.
U-M scientists have now accomplished this goal by inserting a gene called Math1 into non-sensory epithelial cells lining the inner ear. Results from the study will be published in the June 1 issue of the Journal of Neuroscience.
"We found that non-sensory epithelial cells in adult guinea pig cochlea can generate new sensory hair cells following the expression of Math1," says Yehoash Raphael, Ph.D., an associate professor of otolaryngology in the U-M Medical School, who directed the study. "We also found that some of these hair cells can attract the growth of new fibers from auditory neurons."
The paper will be published in the June 1 issue of the Journal of Neuroscience.

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Knee injuries are a common hazard for athletes - especially those who play basketball, volleyball, soccer or other sports where knees are subjected to turning, twisting and jerking.
But a University of Michigan Health System study, presented at the annual meeting of the American Academy of Orthopaedic Surgeons, shows that female athletes may be at an even greater risk for a certain type of knee injury than their male counterparts due to the differences in the muscle structure around the knee.
"Knee muscles are capable of protecting ligaments and preventing injury," says Edward M. Wojtys M.D., professor of orthopaedic surgery, U-M Medical School, and Director of Sports Medicine at UMHS. "Female athletes are two to eight times more likely to tear their anterior cruciate ligament because they may not be able to achieve the same muscle stiffness across the knee joint."
Wojtys calls the U-M study "one piece of the puzzle" in determining the differences between female and male athletes and, consequently, providing for the training and conditioning needs of female athletes in a safe and effective way. Full story.

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U-M Kellogg Eye Center Researcher's High-Speed Images Show How Cells Mobilize for Immune Response

New high-speed imaging techniques are allowing scientists to show how a single cell mobilizes its resources to activate its immune response, a news research study shows. Howard R. Petty, Ph.D., professor and biophysicist at the University of Michigan Health System's Kellogg Eye Center, has dazzled his colleagues with movies of fluorescent-lit calcium waves that pulse through the cell, issuing an intracellular call-to-arms to attack the pathogens within. He explains that these high-speed images provide a level of detail about cell signaling that simply wasn't possible just a few years ago.
In the April 15 issue of the Proceedings of the National Academy of Sciences, Petty provides more detail on cell signaling, depicting what he calls the "molecular machinery" underlying the immune response. He has identified a sequence of amino acids (LTL) that controls the calcium wave pathway and, crucially, the ability of immune cells to destroy targets.
The findings are important because they could eventually lead scientists to design drugs based on the amino acid motif. When a mutation is introduced, phagocytosis is not completed because the calcium wave circles the cell and bypasses the phagosome altogether.
"Our clinical goal," explains Petty, "is to characterize the immune cell's signaling function so that we can interrupt it or somehow intervene when it begins to misfire." The process has implications for treating autoimmune diseases such as arthritis, multiple sclerosis, and the eye disorder uveitis. Full Story.

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Since 1993, Deborah Eadie has worked in the Department of Ophthalmology and Visual Sciences, where she is the unit's research administrator. Eadie's contributions to the department include grant writing, arranging for a leaky piece of equipment to be fixed on a weekend, helping a foreign postdoctoral student find housing and overseeing construction of a complete floor of state-of-the-art laboratories in the Kellogg Eye Center. Colleagues say she performs her duties with "intelligence, efficiency and humor." During Eadie's 10-year tenure, the department's research budget has grown to become the fifth largest in the nation in terms of National Institutes of Health funding. Eadie is "critical to every aspect of our basic clinical research efforts; she's a real problem-solver," say her nominators. Full story.