Bioengineered in Vitro Tissue Model of Fibroblast Activation for Modeling Pulmonary Fibrosis

Area of Science:

• Biomedical Engineering
• Regenerative Medicine
• Pulmonary Biology

Background:

• Idiopathic pulmonary fibrosis (IPF) is a complex lung disease with unknown causes and no cure.
• Existing animal and in vitro models fail to replicate the intricate 3D structure and biochemical makeup of human fibrotic lung tissue.
• Accurate models are crucial for understanding IPF progression and testing new treatments.

Purpose of the Study:

• To create a 3D bioengineered pulmonary fibrotic (Eng-PF) tissue that accurately mimics human fibrotic lung pathology.
• To assess the suitability of silk collagen type I hydrogels and Flexcell bioreactors for this purpose.
• To establish a platform for studying IPF mechanisms and evaluating antifibrotic therapies.

Main Methods:

• Fabrication of 3D Eng-PF tissues using cell-laden silk collagen type I dityrosine cross-linked hydrogels.
• Utilizing customized Flexcell bioreactors to apply mechanical stimuli.
• Incorporating airway epithelial and microvascular endothelial cells to mimic human fibroblastic foci (Hum-FF).

Main Results:

• Silk collagen type I hydrogels demonstrated superior stability and mechanical tunability compared to other systems.
• The Eng-PF model successfully replicated Hum-FF-like pathology.
• The model allowed for the observation of myofibroblast differentiation and evaluation of antifibrotic drugs.
• The system showed potential for modeling epithelial injury and cellular recruitment.

Conclusions:

• The developed 3D Eng-PF tissue is a robust and tunable model for studying IPF.
• This model overcomes limitations of current systems in replicating human fibrotic lung tissue complexity.
• Eng-PF tissues offer a promising platform for advancing IPF research and therapeutic development.