Studying designed modular nano-biotechnological tools to detect and interfere with the key signaling pathway of heart fibrosis using correlative light and cryo soft X-ray tomography

2019 edition

Johannes Groen

The heart affected by a chronic injury, such as aortic stenosis, develops fibrosis and hypertrophy as defense mechanisms to restore function. These protective mechanisms can cause organ failure in the long term. This pathological situation occurs in more than 2% of the population over 65 years old, becoming a socioeconomic problem with no effective medical therapy that ultimately requires aortic valve replacement.

In the present project we are working on the modular design of nano-biotechnological tools with the final aim of inhibiting the fibrotic signaling in myocardial fibrosis. These designed protein complexes combine different functionalities: ligand recognition and fluorescent signaling, which allows tracking in vitro and in vivo.  A previous study has shown that these designed proteins are able to actively inhibit collagen formation without having any apparent negative effects [1].

This project focuses on verifying these findings by providing information regarding the cellular ultra-structure and fate of the protein. The goal is to evaluate the fate and action of these functional structures directly on myocardial fibroblasts, following a high-resolution correlative approach [2]. Visible light super-resolution fluorescence microscopy allows us to locate the fluorescence signal of the designed structures in the cells, and cryo-soft X-ray tomography [3] enables us to locate, correlatively, these same structures within the whole native 3D cellular ultra-structure at a resolution around 50nm.

[1] C√°ceres et al., “Reduction of cardiac TGFő≤-mediated profibrotic events by inhibition of Hsp90 with engineered protein,” Journal of Molecular and Cellular Cardiology, 2018.
[2] Varsano et al., “Development of Correlative Cryo-soft X-ray Tomography and Stochastic Reconstruction Microscopy. A Study of Cholesterol Crystal Early Formation in Cells,” Journal of the American Chemical Society, 2016.
[3] P√©rez-Bern√° et al., “Structural Changes in Cells Imaged by Soft X-ray Cryo-Tomography during Hepatitis C Virus Infection,” ACS Nano, 2016.