Using optical profilometry to characterize cell membrane roughness influenced by amyloid-beta 42 aggregates and electric fields

The membrane roughness of Neuro-2a neroblastoma cells is measured by using noninterferometric wide-field optical profilometry. The cells are treated with the fibril and oligomer conformers of amyloid-beta (A beta) 42, which is a peptide of 42 amino acids related to the development of Alzheimer's disease. We find that both the A beta 42 fibrils and A beta 42 oligomers reduced the cell membrane roughness, but the effect of A beta 42 oligomers was faster and stronger than that of the fibrils. We also apply direct-current electric field (dcEF) stimulations on the cells. A dcEF of 300 mV/mm can increase the membrane roughness under the treatment of A beta 42. These results suggest that A beta 42 can decrease the membrane compliance of live neuroblastoma cells, and dcEFs may counteract this effect. (C) The Authors. Published by SPIE under a Creative Commons Attribution 3.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.