By Leonor Ano '10
San Juan, Argentina
Biochemistry and Molecular Biology
After Mac: PhD program in molecular and cancer biology at Duke University

Have you ever wondered how it is that we manage to stay healthy most of the time, despite the fact that we are made of more cells from outside our body than cells of our own? The answer has to do with one of the most complex components of our body, our immune system. It is crucial to understand how immunity works in order to be able to treat diseases for which no cure has yet been found.

My immunology research in Professor Chatterjea’s lab focused on the study of a group of enzymes called semaphorins. These are a group of traffic molecules that have been studied in the nervous system: they influence the development of neurons by sending them signals of attraction and repulsion. This group of enzymes is also expressed in the immune system, and scientists have observed that they have a range of roles in immunity and autoimmunity. In our lab we analyzed the possible roles of three immune semaphorins: Sema4A, 4D and 7A. T cells are produced in the bone marrow and travel to the thymus where different stages of maturation happen before they are released into the blood. We hypothesized that semaphorins might have a purpose in the blood similar to that in the nervous system: to guide the cells in their process of very directed growth.

Semaphorins may help mature T cells to fulfill their duty of protecting the system against foreign agents.

In addition to this, it is possible that these semaphorins help mature T cells leave the thymus to fulfill their duty of protecting the system against foreign agents. Discovering bits of information about semaphorins can bring us closer to deciphering the intricate developmental trajectory of immune cells and problems related to T cell development and autoimmune diseases. This research gave me great preparation for graduate studies in the sciences.