PT  - JOURNAL ARTICLE
AU  - SangYun Lee
AU  - HyunJoo Park
AU  - Kyoohyun Kim
AU  - YongHak Sohn
AU  - Seongsoo Jang
AU  - YongKeun Park
TI  - Refractive index tomograms and dynamic membrane fluctuations of red blood cells from patients with diabetes mellitus
AID  - 10.1101/087460
DP  - 2016 Jan 01
TA  - bioRxiv
PG  - 087460
4099  - http://biorxiv.org/content/early/2016/11/14/087460.short
4100  - http://biorxiv.org/content/early/2016/11/14/087460.full
AB  - 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.