Abstract
Purpose :
The lens fibrotic disease, posterior capsule opacification (PCO), is a pathological response to cataract surgery. PCO is characterized by the emergence of alpha smooth muscle actin-expressing myofibroblasts, pathologically linked to the excessive production of extracellular matrix that accumulates and ultimately results in a loss of vision. It is unclear what factors divert an injury response to cataract surgery wounding toward fibrosis.
Methods :
Using an ex vivo post-cataract surgery model, we performed RNAseq analysis and a computational pattern analysis approach to identify and compare differential gene expression patterns between the normal wound healing response and the development of fibrosis. RNAseq analysis was performed on an ex vivo post-cataract surgery chicken model from the time of injury through day 1 (D1), D2 and D3. By day 3, wound healing is completed across the endogenous lens basement membrane, and myofibroblasts emerge as part of the fibrotic response within a distinct pro-fibrotic microenvironment. We used comparative pattern analysis (COMPACT), a data analysis approach that exhaustively enumerates the possible dynamic patterns of gene expression changes over time and compares the abundance of these patterns across conditions.
Results :
COMPACT analysis allowed gene expression dynamics to be visualized temporally, revealing subtle and dominant patterns of genes, including differentially expressed genes that were uniquely upregulated or downregulated with fibrosis compared to wound healing and vice versa. We focused on a pair of patterns that represented an early divergence of gene regulation between wound healing and fibrosis that then persisted into 3 days. Progression of wound healing involved the persistent upregulation of genes linked to the regulation of WNT signaling, Rho GTPase family function, cytoskeleton, lipid signaling, and cell adhesion. Transition to a fibrotic phenotype involved persistent upregulation of genes associated with regulating signal transduction, including distinct phosphatase and serine/threonine kinases, as well as the contractility of cells.
Conclusions :
Our results are starting to map the molecular transitions that govern wound healing versus the fibrotic response to lens injury.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.