Pulmonary fibrosis is a progressive and fatal disease that results from the deposition of collagen (essentially scar tissue). In normal lungs, collagen expression is limited to the major airways with small amounts in the larger blood vessels. But in the fibrotic lung, collagen is deposited throughout the organ, eventually causing death due to the inability of the lung to adequately transfer oxygen into the bloodstream.
During the start of the COVID lockdown, I developed a new method for the 3D reconstruction of tissue collagen. CT scanning is typically used to visualize pulmonary fibrosis but this method relies on tissue density, which does not specifically indicate the localization of collagen. Using a large set of stacked, serial tissue sections stained with picosirius red (which specifically stains collagen) from both normal and fibrotic lungs, I was able to generate a 3D model of the collagen expressed in both normal and fibrotic lung tissue. Each layer was converted into a polygonal mesh and then combined together into the final models. ZBrush and Keyshot were used for the visualization due to the fact that they were the only programs that could easily handle the high polygon count.
These models were published in the manuscript Redente EF, et al, Am J Respir Cell Mol Biol. 2021 Jun;64(6):669-676 (https://pubmed.ncbi.nlm.nih.gov/33406369/). Stained lung section images were provided by the Redente Lab at National Jewish Health, Denver, CO.