Cell signaling is the process by which cells detect changes within their microenvironment and elicit an appropriate response, e.g. a change in metabolic activity and signaling to other cells. Understanding the underlying molecular mechanisms is one of the main quests of biology, but cell signaling studies remain difficult due to the high number of involved factors and their ensemble actions.
The main biological interest of our group here is the activity of the AKT/mTOR pathway in the differentiation and growth process of adipocytes and pancreas cells. The Akt/mTOR pathway is a major pharmaceutical target to combat insulin resistance in adipocytes and insulin production of pancreas cells occurring during diabetes mellitus. We apply automated microfluidic cell culture chip technologies to precisely control stem cell differentiation on chip by activating or silencing the Akt/mTOR pathways. In contrast to standard cell culture technologies we modulate the simulation pulses over short and long term in their frequency, amplitude and duration on chip to simulate the natural and disease cell micro-environments.
To reveal cellular signal transduction in situ, we either use our biological and micromechanical sensor systems or immuno-based PCR methods for proteins. With these sensors we aim to measure changes in physical-chemical properties (pH, or oxygen) and small molecules (glucose, amino acids) in the surrounding volume or directly within the cells. With the immuno-PCR based technologies, including the proximity ligation assay, we aim to detect changes in abundance, modification and localization of signaling proteins on a single-cell level with high sensitivity and specificity. Specifically, we are highly interested in detecting the whole Akt/mTOR signaling pathways in response to insulin.