Multimodal Label-Free Imaging to Assess Compositional and Morphological Changes in Cells During Immune Activation

Abstract

First I would like to acknowledge the support of the Uehara Foundation, who supported the research discussed here. Aside from financial support, which is crucial, members of the foundation also expressed their interest in developing new ways to visualize and measure cellular processes. Other recipients of Uehara support also were enthusiastic and provided useful feedback and support of this research. It has been an honor to be a part of this program. I would also like to thank the members of my lab, especially Dr. Nicolas Pavillon and Dr. Alison Hobro, without whom this work would not have been what it is. Also my colleagues and collaborators, particularly in Raman imaging at Osaka university, and in immunology at our institute have been very supportive. Since joining the IFReC immunology institute, our lab research has been aimed at creating new optical tools to understand some of the less clear aspects of the immune response, especially on the single-cell level. Most of the tools used by researchers to study the cell response involve tagging specific target molecules and seeing how they are expressed in different cell types, and determining how that expression changes during dynamic processes such as the stimulation of different immune pathways. There are a large number of pathways, signaling ions, expression levels of different proteins, RNA, and more that can be targeted (Spiller et al. 2010) and this number continually grows as researchers unlock new information on how the cell is built, and how it responds. The growing number of known pathways means that at any given time, we have had, and continue to have, only a partial view of the basic mechanisms of the cell. This is where the developments in this project can play a role: using label-free optical methods to interrogate the cell, we are able to analyze changes in molecular content and morphology which can correlate with how the cell is responding to immune stimulation. This approach does not give the same level of specificity as using fluorescent markers, PCR, or other analytical