There is a growing need for the development of a system to measure cell transmigration in a dynamic environment. Such a system would help to monitor the cellular immune response in patients with immunodeficiencies, diabetes, autoimmune diseases, or under chemotherapy. It can be an alternative for experimental animal models in inflammation and cancer biology capable of dissecting, in vitro, the mechanisms of metastasis. The proposed system will automatically measure the number of cells that attach to an adhesive substrate under flow and transmigrate subsequently throughout microscopic passage sensors. Current technology works in static conditions and requires highly trained personnel to operate. It is well known that blood presents critical dynamic features such as leukocyte margination, which selectively presents the flowing leukocytes to the reactive vessel wall. Rainmaker Technology's goal is to generate an automatic migration sensor operating in a flowing environment. In this Phase I project it is planned to: (1) make a prototype sensor with microfabrication technology, and (2) fabricate and validate prototype benchtop instrumentation to operate the sensor. A prototype version of a fully integrated device is justified since the methods developed will prepare the way for chip fabrication, integration and interface with electronics.