Original Research ARTICLE
Single cell imaging of nuclear architecture changes
- 1Living Systems Institute, College of Engineering, Mathematics and Physical Sciences, University of Exeter, United Kingdom
- 2University of Exeter, United Kingdom
- 3Cell Biology, Institute of Experimental Immunology, Faculty of Medicine, University of Zurich, Switzerland
The dynamic architecture of chromatin, the macromolecular complex comprised primarily of DNA and histones, is vital for eukaryotic cell growth. Chemical and conformational changes to chromatin are important markers of functional and developmental processes in cells. However, chromatin architecture regulation has not yet been fully elucidated. Therefore, novel approaches to assessing chromatin changes at the single-cell level are required. Here we report the use of FTIR imaging and microfluidic cell-stretcher chips to assess changes to chromatin architecture and its effect on the mechanical properties of the nucleus in immune cells. FTIR imaging enables label-free chemical imaging with subcellular resolution. By optimizing the FTIR methodology and couple it with cell segmentation analysis approach, we have identified key spectral changes corresponding to changes in DNA levels and chromatin conformation at the single cell level. By further manipulating live single cells using pressure-driven microfluidics, we found that chromatin decondensation – either during general transcriptional activation or during specific immune cell maturation – can ultimately lead to nuclear auxeticity which is a new biological phenomenon recently identified. Taken together our findings demonstrate the tight and, potentially bilateral, link between extra-cellular mechanotransduction and intra-cellular nuclear architecture.
Keywords: B cell, Auxeticity, nuclear achitecture, Chromatin, Infrared Microscopy, Microfluidics
Received: 03 Apr 2019;
Accepted: 10 Jul 2019.
Edited by:Venkaiah Betapudi, US Army Medical Research Institute of Chemical Defense, United States
Reviewed by:Sophie A. Lelièvre, Purdue University, United States
John W. Peterson, Cleveland Clinic, United States
Scott T. Retterer, UT-Battelle, United States
Copyright: © 2019 Morrish, Hermes, Metz, Stone, Pagliara, Chahwan and Palombo. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
Dr. Stefano Pagliara, Living Systems Institute, College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter, EX4 4QD, England, United Kingdom, S.Pagliara@exeter.ac.uk
Prof. Richard Chahwan, Institute of Experimental Immunology, Faculty of Medicine, University of Zurich, Cell Biology, Zurich, 10461, NY, Switzerland, firstname.lastname@example.org
Prof. Francesca Palombo, University of Exeter, Exeter, EX4 4PY, England, United Kingdom, F.Palombo@exeter.ac.uk