TY - JOUR T1 - Refractive index tomograms and dynamic membrane fluctuations of red blood cells from patients with diabetes mellitus JF - bioRxiv DO - 10.1101/087460 SP - 087460 AU - SangYun Lee AU - HyunJoo Park AU - Kyoohyun Kim AU - YongHak Sohn AU - Seongsoo Jang AU - YongKeun Park Y1 - 2016/01/01 UR - http://biorxiv.org/content/early/2016/11/14/087460.abstract N2 - In this paper we present the optical characterisations of diabetic red blood cells (RBCs) in a non-invasive manner employing three-dimensional (3-D) quantitative phase imaging. By measuring 3-D refractive index tomograms and 2-D time-series phase images, the morphological (volume, surface area and sphericity), biochemical (haemoglobin concentration and content) and mechanical (membrane fluctuation) parameters were quantitatively retrieved at the individual cell level. With simultaneous measurements of individual cell properties, systematic correlative analyses on retrieved RBC parameters were also performed. Our measurements show that diabetic patients had RBCs of reduced cell sphericity and elevated intracellular haemoglobin concentration and content compared to healthy (non-diabetic) subjects. Furthermore, membrane deformability of diabetic RBCs is significantly lower than that of healthy, non-diabetic RBCs. Interestingly, non-diabetic RBCs exhibit strong correlations between the elevated glycated haemoglobin in RBC cytoplasm and decreased cell deformability, whereas diabetic RBCs do not show correlations. Our observations strongly support the idea that slow and irreversible glycation of haemoglobin and membrane proteins of RBCs by hyperglycaemia significantly compromises RBC deformability in diabetic patients. ER -