title: Silver nanoparticle-induced degranulation observed with quantitative phase microscopy.
abstract: Monitoring a degranulation process in a live mast cell is a quite important issue in immunology and pharmacology. Because the size of a granule is normally much smaller than the resolution limit of an optical microscope system, there is no direct real-time live cell imaging technique for observing degranulation processes except for fluorescence imaging techniques. In this research, we propose optical quantitative phase microscopy (QPM) as a new observation tool to study degranulation processes in a live mast cell without any fluorescence labeling. We measure the cell volumes and the cross sectional profiles (x-z plane) of an RBL-2H3 cell and a HeLa cell, before and after they are exposed to calcium ionophore A23187 and silver nanoparticles (AgNPs). We verify that the volume and the cross sectional line profile of the RBL-2H3 cell were changed significantly when it was exposed to A23187. When 50 microg/mL of AgNP is used instead of A23187, the measurements of cell volume and cross sectional profiles indicate that RBL-2H3 cells also follow degranulation processes. Degranulation processes for these cells are verified by monitoring the increase of intracellular calcium ([Ca(2+)](i)) and histamine with fluorescent methods.
authors.affiliation: Department of Information and Communications, Gwangju Institute of Science and Technology, Buk-gu, Gwangju, Republic of Korea. wzyang@gist.ac.kr
authors.forename: Wenzhong
authors.initials: W
authors.lastname: Yang
authors.forename: Seungrag
authors.initials: S
authors.lastname: Lee
authors.forename: Jiyong
authors.initials: J
authors.lastname: Lee
authors.forename: Yoonsung
authors.initials: Y
authors.lastname: Bae
authors.forename: Dugyoung
authors.initials: D
authors.lastname: Kim
mesh_terms: D015550:Cell Degranulation / Q000187:drug effects* / Q000502:physiology*; D006367:HeLa Cells; D006801:Humans; D008407:Mast Cells / Q000187:drug effects* / Q000473:pathology*; D008858:Microscopy, Phase-Contrast / Q000379:methods*; D053758:Nanoparticles / Q000008:administration & dosage*; D012834:Silver / Q000494:pharmacology*
chemical_list: D012834:Silver