Sarah McLeod is examining the role of a protein, Rap 1 GTPase, in regulating essential cells in the immune system. In her previous research, McLeod discovered that this protein activates after B cells bind with antigens (substances that stimulate an immune response). Now McLeod is furthering that research by studying whether activation of the protein regulates the B cell activity, which enables the cells to produce antibodies for defense against harmful microbes and other infectious agents. Determining the overall function of Rap 1 in B cells and understanding how the protein regulates B cell adhesion and migration may provide insights into how these processes are regulated in B cells and other cell types.