Abstract 5395: High-throughput cysteine concentration determination by specific fluorescence sensors in cell culture medium
Authors: Guan Hong 
Published: May 2015

Abstract
Cysteine is a sulfur-containing amino acid that can be biosynthesized in human (1). It is not stable in free solution and can be auto-oxidized to cystine. Cystine is more stable and can travel freely through the blood (2). After intracellular accumulation by different transporters, especially Xc-transporter (3, 4), cystine will be rapidly reduced to cysteine which can then be used to synthesis protein or glutathione (GSH) synthesis5. Cysteine may also release from the cells by Alanine-Serine-Cysteine transporter (3). The accumulation of cysteine can feed other cells with low expression or mutation of Xc-transporter. It has been reported that stromal cells can promote cancer cell survival by the control of cystine metabolism to cysteine(5).
Cysteine concentration distribution now may affect cell survival and cell-cell signaling (2, 5). It is still hard to study the total cysteine concentration in different culture system or in vivo in a high-through put way. Traditional LC-MS methods are not only cumbersome and time consuming, it also hard to process different samples in parallel. Here we report a series of novel fluorescent sensors which have great selectivity and sensitivity towards cysteine. Using these sensor compounds, we can monitor cysteine level in situ in cell culture system. Upon screening different culture medium, we found cysteine concentrations are different with cell type and culture time. We envision our fluorescent probes can be used to elucidate cysteine's function in cell survival as well as signal transduction between cells.
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Citation Format: Hong Guan. High-throughput cysteine concentration determination by specific fluorescence sensors in cell culture medium. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5395. doi:10.1158/1538-7445.AM2014-5395