A108 - Simultaneous multiplexed staining of the infarcted area and Connexin-43 on wide thick heart sections

Guillaume Pidoux (guillaume.pidoux@inserm.fr)
Matthieu Cortes (matthieu.cortes@curie.fr)

Myocardial infarction (MI) is one of the major causes of death in industrialized countries and is characterized by a prolonged cardiac ischemia usually triggered after blood clot, coronary artery constriction or atherosclerosis. This leads to irreversible cardiomyocyte death and impairs cardiac function. Ischemia will engender the cardiac scar in acute phases of MI and affects proteins expression and localization at the proximal area (ie. area at risk). In this context, the expression et subcellular location of the gap junction connexin-43 (Cx43) protein are affected in cardiomyocytes after MI, which trigger arrythmias occurrence and fatal death. However, the full characterization of these changes between each areas remain elusive. It is challenging to image and reconstruct in 3D an entire heart section with a structural study of the infarcted area in classical histology and simultaneously combine multiplexing fluorescence analyses of proteins of interest behavior and their subcellular distribution in the proximal and healthy zones. To do so, we will be utilizing the latest generation of spinning disk technology, which boasts a wide field of view and modular pinholes. This cutting-edge technology is ideal for rapidly acquiring and reconstituting deep tissue mosaics, providing a real field of 25mm and homogeneous illumination. Our focus will be on imaging sections of infarcted hearts using a customizable spinning disk with custom pinhole sizes and various pattern distributions. Moreover, we will explore various options for acquiring mosaics, including low magnification techniques, with the goal of reconstructing our samples in 3 dimensions while minimizing any overlapping areas. By varying the magnification levels and the resolution, we will be able to study two critical aspects: i) the size of the infarct using TUNAL and ii) a precise Cx43 localization and expression in all areas of the heart. Through these efforts, we hope to gain new insights into the propagation