(F1331) CIRCULAR RNA-MEDIATED PARTIAL REPROGRAMMING AS A NOVEL THERAPEUTIC STRATEGY FOR IDIOPATHIC PULMONARY FIBROSIS VIA REVERSING PATHOLOGICAL CELL STATES OF ALVEOLAR EPITHELIAL CELLS AND LUNG FIBROBLASTS
Guangzhou National Laboratory Guangzhou, China (People's Republic)
Abstract: Idiopathic pulmonary fibrosis (IPF) is a progressive and fatal lung disease characterized by excessive deposition of extracellular matrix and the transformation of alveolar epithelial cells and fibroblasts into pathogenic cell states. In this study, we explored the therapeutic potential of partial reprogramming (PR) using lipid nanoparticles (LNPs) encapsulating circular RNAs (circRNAs) encoding OCT4, SOX2, and KLF4 (OSK) to treat IPF. Partial reprogramming is an innovative approach that aims to revert cells to a more youthful and regenerative state without inducing pluripotency. This technique involves the transient expression of reprogramming factors, such as OCT4, SOX2 and KLF4, which can induce cellular rejuvenation. The utilization of circRNAs for expressing PR factors offers several advantages, including their stability and low immunogenicity, making them an efficient and safe gene delivery vector for therapeutic applications. Our results demonstrated that PR treatment effectively reversed TGFβ-induced epithelial-to-mesenchymal transition (EMT) phenotypes in alveolar epithelial cells, as evidenced by the upregulation of epithelial markers such as E-cadherin and the downregulation of mesenchymal markers such as N-cadherin and vimentin. RNA-seq analysis showed that this reversal was mediated through the TGFβ, WNT, and PI3K signaling pathways. Besides EMT markers, PR treatment also upregulated the AT2 cell markers such as SFTPB, SFTPC and SFTPD, indicating recovering cells to a more regenerative state. Additionally, PR also reversed the fibroblast-to-myofibroblast transition (FMT) in lung fibroblasts, with downregulation in FMT markers such as collagen type I (COL1A1) and α-smooth muscle actin (α-SMA). Moreover, the effects of PR treatment in reversing pathological cell states of alveolar epithelial cells and lung fibroblasts outperformed those of pirfenidone (PFD) treatment. To further validate these findings, we established an IPF model using lung organ-on-a-chip technology, which confirmed the therapeutic effects of PR treatment. This study provides a novel therapeutic strategy for IPF by leveraging the regenerative capacity of cells through partial reprogramming using LNP-encapsulating circRNAs, offering a promising avenue for future clinical interventions.
