De Tomaso focuses on what happens when one sea squirt lands next to another. In this case, cells in the sea squirt's fingerlike edges, or "ampullae," recognize the neighboring sea squirt as "self" or "non-self." When the other sea squirt is related, then the two colonies fuse; otherwise, they reject each other. De Tomaso was involved in identifying the gene controlling the choice between fusion and rejection in the sea squirt when he was a postdoctoral fellow at Stanford University
In his current research, De Tomaso studies how the signals on the surface of the sea squirt's cells get translated inside the circuitry of the cell, where the final decision about acceptance or rejection is made. "In the case of Botryllus, what we found is that we have the same kind of integration that goes on in humans, but instead of having a multiple, very complex set of inputs coming in, we only have two," said DeTomaso. "We have also found that we can manipulate each one independently, so we know that somehow they are put together and the two inputs are integrated, and a decision is made about how to respond."
De Tomaso explained that he decided to work on Botryllus because it has a unique way to answer a very complicated question. He hopes to understand the process of rejection or acceptance. "If we could manipulate that process," said Tomaso, "then we could basically teach the immune system to simply ignore certain things. We could say, 'Just don't respond to this. We're going to transfer this bone marrow, just don't kill this bone marrow.' Bone marrow could get in and start making new blood, and it would be fine. To me, that's the most exciting thing long-term for the work."
|Contact: Gail Gallessich|
University of California - Santa Barbara