Each year, nearly 1/2 billion people suffer from dengue infections, and there is currently no effective vaccine or drug therapy available [1]. This mosquito-borne virus causing flu-like illness, which can be fatal, is a serious threat to many in tropical and sub-tropical countries even now touching southern Florida and Texas.  Vaccines must immunize against all five viral serotypes to be effective making them challenging to develop. Dr. Ken Jacobson, Kenan Distinguished Professor of Cell Biology and Physiology at the University of North Carolina at Chapel Hill, studies basic cell biology and membrane biophysics to investigate the attachment of dengue virus to the cell membrane and the subsequent steps of dengue virus infection. Dr. Jacobson not only conducts basic science research that may help lead to a dengue virus vaccine, but also merges physics with biology to develop a solar powered thermoelectric vaccine cooler to preserve vaccines, including those developed for dengue virus. This will permit more effective delivery of vaccines in the rural developing world.

Breaking new ground in scientific discovery and technique development, Dr. Jacobson was one of the early developers of digitized fluorescence microscopy who introduced its applications to cell biology. Probing cell biology from a physical perspective, Dr. Jacobson created these tools to measure the traction forces the cell must apply to crawl on a surface, and to “photomanipulate” the proteins involved in cell migration using laser beams. Currently, Dr. Jacobson works with theoreticians to further understand morphologically oscillating cells as a model for amoeboid cell migration important in cancer metastasis. A significant contributor to what is now termed the “Renaissance of Light Microscopy,” Dr. Jacobson continues to leverage high-resolution imaging techniques both in the study of dengue virus infection -- for further breakthroughs in vaccine development -- and to understand the mechanisms of amoeboid cell movement.

Current research includes:

• Dengue Virus Infection, Vaccine Development and Delivery: Collaborating with a prominent dengue researcher and a well-known biophysical chemist at UNC, Dr. Jacobson is studying very tiny protein clusters on the cell membrane termed nanoclusters or nanodomains, that are important receptors on dendritic cells for multiple pathogens, particularly the dengue virus. Using fluorescence microscopy to examine the clusters on the scale of 100 nanometers or less, Dr. Jacobson and his team investigate how dengue virus bound to the cell surface receptors moves laterally to sites of internalization and then how receptors traffic the virus to finally produce infection. Ultimately, Dr. Jacobson hopes to identify where in the process antibodies that block dengue infection act. This basic research is important in the development of a successful dengue vaccine.

  In the rural developing world, expensive vaccines are degraded due to overheating or freezing in outmoded ice chests, resulting in a loss of confidence in treating the populations because the vaccines administered are impotent. Therefore, and complementing his basic research, Dr. Jacobson has been also interested in more effective delivery of vaccines in the rural developing world.  He and his group are developing a solar powered thermoelectric vaccine cooler in which vaccines are kept at the proper temperature in portable coolers run on batteries charged by on-board solar panels. This work is done by undergraduate students, through UNC programs designed to inspire undergraduate students considering research as their career.

• Cell Motility: Dr. Jacobson’s second biomedical research interest involves the question of how cells move. In particular, his group is studying cells whose shape oscillates in a periodic fashion, termed the periodically protruding phenotype. This is a basic research project and provides a test bed for needed new theoretical approaches to modeling motile phenomena. It is important that the periodically protruding phenotype is likely a model for a key type of amoeboid migration that is significant in development and to the spread of metastatic cancer.