A team of researchers from the Massachusetts Institute of Technology (MIT), Harvard Stem Cell Institute, Harvard Medical School and the Bigham &Women’s Hospital (BWH) have developed an aptamer-based nanosensor, which could monitor real-time, both in in vivo and in vitro, the communication of individual cells between each other and with the environment by attaching them to the surface of living cells.
They have made use of the cell membrane linked sensors to detect quantitatively the interaction of the target molecules and the mesenchymal stem cells.
With a modification of the generic approach, a range of cellular interactions could be detected and would be a facilitator for developing a broad toolkit containing cell surface sensors, which would be used in cell biology research and drug development. According to Jeffrey M Karp, Weian Zhao and other team members, this technique could be utilized in vivo for tracking the transplanted cells and even help to find out the drug response for individual patients at the cellular level. A paper titled ‘Cell Surface sensors for real-time probing of cellular environments’ have been published in Nature Nanotechnology by these scientists, reporting this development.
Jeffrey Karp, who is the co-director of the Center for Regenerative Therapeutics at BWH and his colleagues, have revealed that tracking the cells and their response real-time to cytokines and other surrounding signals still prove to be a major stumbling block. Dr. Karp’s team of researchers have created a sensor that would attach fluorescent aptamers covalently to the cell membrane and thus help to generate a real-time signal whenever a target molecule is in contact with the cell surface. Thus this method does not make use of any the complex enzymatic, genetic or metabolic engineering methods to alter the cell surface and instead makes use of three steps, wherein the cell surface amines are treated with sulphonated biotinyl-N-hydroxy-succcinimide (NHS-biotin) and then with streptavidin-biotin interactions. The major advantages obtained by the cell surface sensor technique would be the possibility of detecting local target molecule concentrations very close to or at the cell surface, thus proving to be very different over methods such as ELISA.