Cell-surface thiols

The injectable gold drugs such as AuSTm and AuSTg are not readily taken up by most cells. Yet it is clear that they can bind to cell surface thiols and by such a mechanism may affect the cells overall metabolism. As discussed in a subsequent section, cyanide alters the situation and facilitates gold uptake in red cells. 

Moreover, quenching of AFR by Ehrlich ascites cells (measured by electron spin resonance) has been demonstrated to occur and to depend on the cell viability, surface charge, and cell-surface thiol groups (Pethig et al, 1984, 1985). 

The cell-surface thiols can be used as a biomarker to predict skin sensitization (Suzuki, Hirota, Hagino, Itagaki, Aiba, 2009). THP-1 cells (human monocytic cells, activated macrophages) change intracellnlar signaling and cell-surface thiols in response to various chemicals. Thiolated polymers and their particles have the possibility of being used as skin-sensitization biomarkers. 

Suzuki, M., Hirota, M., Hagino, S., Itagaki, H., Aiha, S. (2009). Evaluation of changes of cell-surface thiols as a new hiomarker for in vitro sensitization test. Toxicology In Vitro, 25(4), 687-696. 

Torres, A. G., Gait, M. 1. (2012). Exploiting cell surface thiols to enhance cellular uptake. Trends in Biotechnology, 50(4), 185-190. 

Sampathkumar S-G, Li AV, Jones MB, Sun Z, Yarema KJ. Metabolic installation of thiols into sialic acid modulates adhesion and stem cell biology. Nat. Chem. Biol. 2006 2 149-152. Mahal LK, Yarema KJ, Bertozzi CR. Engineering chemical reactivity on cell surfaces through oligosaccharide biosynthesis. Science 1997 276 1125-1128. 

Thiols Have Versatile Chemistry but Are not Unique to the Cell Surface. 2179... 

Figure 10-7 Cell adhesion and control of stem cell fate through MOE (A) metabolic incorporation of AcsManNTGc (10) results in the replacement of the natural cell surface sialic acid NeuSAc with the thiol-containing counterpart NeuSTGc (B) glycocalyx-displayed thiols are ideally situated to attach to exogenous surfaces with complementary chemical properties such as gold (C) Novel carbohydrate-mediated thiol-gold cell adhesion leads to the differentiation of human embryonic cells to neurons as described in detail in ref. 32.

Sampathkumar, S.-G., Jones, M. B., Yarema, K. J. (2006). Metabolic expression of thiol-derivatized sialic acids on the cell surface and their quantitative estimation by flow cytometry. Nat. Protocols, 1, 1840-1851. 

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