Poster BB11 - A 3D Biomimetic Lung Organ Tissue Equivalent (OTE) Model for Pulmonary Fibrosis Studies

Friday, October 25, 2024

3:30 PM - 4:30 PM EST

Location: Exhibit Hall E, F & G

Presenting Author(s)

Vikram Surendran

Graduate Student/ Graduate Research Assistant
Wake Forest Institute for Regenerative Medicine/Wake Forest School of Biomedical Engineering and Sciences
Winston-Salem, North Carolina, United States

Co-Author(s)

TL

Timothy Shane Leach, PhD (he/him/his)

Postdoctoral Fellow
Wake Forest Institute for Regenerative Medicine, United States
DS

Douglas Edward Shankle

Research Technician III
Wake Forest Institute for Regenerative Medicine, United States
Phillip W. Clapp, PhD

Assistant Professor
University of North Carolina at Chapel Hill, United States
AA

Anthony Atala, MD

Chair/Professor
Wake Forest Institute for Regenerative Medicine/Wake Forest School of Biomedical Engineering and Sciences, United States

Primary Investigator(s)

Sean Vincent Murphy (he/him/his)

Academic Faculty/Associate Professor
Wake Forest Institute for Regenerative Medicine, United States

Introduction: Lung fibrosis is a life-threatening lung condition with an average survival of 2-3 years from diagnosis. It is characterized by excessive fibroblast differentiation, elevated extracellular matrix (ECM) deposition, stiffening of lung tissue, and ultimately affecting lung function. The risk factors of lung fibrosis include, but are not limited to; smoking, toxic environmental exposures, chronic viral infections, genetic predispositions, and drug side effects. Unfortunately, effective therapeutic options are still lacking, with only two anti-fibrotic drugs which are FDA-approved, and which only slow, not reverse the disease process. The major drawback limiting the development of new effective drugs for lung fibrosis is the lack of suitable predictive pre-clinical in-vivo and in-vitro models. Traditionally, animal models have been widely used in preclinical trials. However, they are limited by its spontaneous reversibility of induced fibrosis without treatment, very expensive, labor-intensive, low throughput, and often exhibit differential fibrosis pathology compared to humans. Ultimately all these results in poor correlation of preclinical models with human disease. So consequently, the in-vitro models of lung fibrosis have emerged as a critical platform to provide insight into the pathological mechanisms of fibrosis and aid in therapeutic development. However current in-vitro models of lung fibrosis lack the complexity of native human tissues, such as an accurate 3D multi-cell type microarchitecture, and biologically relevant cell-cell and cell-matrix interactions. So, there is a need for a better biomimetic multi-cellular in-vitro 3D model that can better recapitulate in-vivo-like cell-cell and cell-matrix interactions essential for accurately modeling fibrosis pathophysiology

Materials and

Methods: To overcome this limitation, we developed a multi-cellular 3D biomimetic OTEs model that recapitulates the 3D microarchitecture, cell-cell, and cell-matrix interactions of human lung tissue. This is achieved by establishing mature primary lung bronchial epithelial cells at an air-liquid interface(ALI), cultured on a stroma comprising native extracellular matrix (ECM) deposited by a 3D layer of primary lung fibroblasts. The model replicates the multicellular organization similar to that of native airway tissue by forming a fully differentiated pseudostratified bronchial epithelium and stromal layer. Then 3D lung OTEs are exposed to TGF-β to induce fibrosis. we evaluated their fibrotic response by quantifying the expression of key fibrotic markers like α-SMA (immunohistochemistry (IHC)), collagen fiber remodeling (CT-FIRE), and ECM deposition (IHC), TIMPs/MMP(ELISA) and compared with healthy 3D lung OTE (non-treated).

Results, Conclusions, and Discussions: In this study, We have demonstrated that the model generates fully functional epithelial cells, including the formation of cilia, mucus production, and basal stem cell niches. The OTE stroma shows an accurate cell:ECM composition, a well-organized, collagen-rich ECM organization(Figure.1).3D lung OTEs were exposed to TGF-β for three weeks while maintaining the integrity of the model. We have shown that significantly greater expression of key fibrotic markers like α-SMA, collagen fiber remodeling, MMPs, and ECM deposition was observed upon induction of fibrosis by TGF-β.This effect is diminished upon treatment with an anti-fibrotic drug (Nintedanib). Also, Nanostring gene expression-assisted pathway analysis showed upregulation of genes associated with the fibrosis pathway. This study demonstrated that the proposed model is capable of recapitulating certain critical in-vivo-like lung fibrotic pathophysiology, making this an extremely valuable tool for translational research and could be used for reliable studies of pulmonary fibrosis and drug screening. This also illustrates one of the unique possibilities of conducting long-term in vitro fibrosis studies, akin to animal-based fibrosis models. The development of the 3D lung OTE model serves as an alternative to traditional animal models of lung fibrosis. By utilizing this human-derived cells and biomimetic culture conditions, the need for animals in preclinical studies of fibrosis can be reduced or eliminated, thereby replacing the use of animals in certain experimental contexts. This model would have immediate translational potential to elucidate the pathophysiology of fibrotic disease, and thereby improve treatments.

Acknowledgements (Optional):