MCF-7/BOS cells membrane proteome profiling for the analysis of plasmic proteins in pancreatic beta cells

Type I and type II diabetes are diseases characterized by the activation of the apoptotic processes in pancreatic islet of beta-cells.
To highlight specific proteins of beta cells in medical imaging (positron emission tomography or PET), the development of antibodies directed against membrane markers of the beta cells is undertaken. These membrane markers have to be accessible to antibodies and should be potential therapeutic targets.
In order to isolate membrane proteins of beta cells, preliminary tests were conducted on MCF-7 / BOS cell line, immortal and easier to cultivate. The goal of this work is to obtain a pure membrane fraction to facilitate the analysis of the sample.
To isolate transmembrane proteins, we compared two methods. The first one used a differential centrifugation to isolate membrane proteins. The second method labelled accessible extracellular domains at the surface of MCF-7 cells with biotin prior to differential centrifugation.

The labelling technique used can provide 50% of membrane proteins. This second method will be used to isolate membrane proteins of pancreatic beta cells.