A new 3-D view of the body's response to infection - and the ability to identify proteins involved in the response - could point to novel biomarkers and therapeutic agents for infectious diseases.
Vanderbilt University scientists in multiple disciplines combined magnetic resonance imaging (MRI) and imaging mass spectrometry to visualize the inflammatory response to a bacterial infection in mice. The techniques, described in Cell Host & Microbe and featured on the journal cover, offer opportunities for discovering proteins not previously implicated in the inflammatory response.
Access to unique resources at Vanderbilt made the unprecedented 3-D infection imaging possible, said Eric Skaar, Ph.D., Ernest Goodpasture Chair in Pathology and one of the senior co-authors of the paper.
"The studies in this paper couldn't have happened at any other university, because the resources simply don't exist at most schools," Skaar said.
The resources include animal imaging technologies available through the Vanderbilt University Institute of Imaging Science (VUIIS), directed by John Gore, Ph.D., and imaging mass spectrometry technologies available through the Mass Spectrometry Research Center (MSRC), directed by Richard Caprioli, Ph.D. Gore and Caprioli are also senior co-authors of the paper.
"The fact that my research group, which studies infectious diseases, has access to these powerful imaging and mass spectrometry technologies is a real strength at Vanderbilt and has allowed us to develop these new tools that will enable high impact discovery," Skaar said.
Skaar and his team were interested in imaging infection in three dimensions - in the whole animal - while also being able to identify the proteins that are produced at sites of infection. MRI provides detailed anatomical images of tissue damage. Imaging mass spectrometry is a unique technology that directly measures proteins, lipids and other metabolites and maps their distribution in a biopsy or other tissue sample.
Ahmed Attia, Ph.D., a former member of Skaar's group now on the faculty at Cairo University, Egypt, infected mice with Staphylococcus aureus, a major cause of human disease. He then delivered the infected animals to Daniel Colvin, Ph.D., in the VUIIS, who imaged them with MRI. Kaitlin Schroeder and Erin Seeley, Ph.D., in the MSRC then conducted imaging mass spectrometry studies. Putting together the two technologies and multiple data sets accurately required the expertise of Kevin Wilson, MESc, in the VUIIS, who developed algorithms to show consolidated 3-D views of the inflammatory response.
"This is another example of the multi-modality approach we have been pursuing in general within the Imaging Institute," Gore said.