Development of Decellularized Lung Tissue with Sex as a Biological Variable

Abstract

The lung is a complex structure consisting of a network of various cell types, and a diverse extracellular matrix (ECM). The varied composition of this tissue poses a significant challenge for study and replication in vitro. Previous attempts in tissue engineering have failed to capture the multifaceted biomechanical cues that regulate tissue homeostasis in the lung, as they are often focused on enriching a single type of ECM protein in the developed scaffold. To address this limitation and gain a comprehensive understanding of lung mechanobiology, a 3D scaffold derived from porcine decellularized lung tissue is proposed. It is hypothesized that the levels of ECM proteins in lung tissue may vary based on sex due to differences in disease incidence and outcomes demonstrated between male and female patients. This variation in protein levels may affect the interactions between cells and the extracellular matrix, potentially influencing the susceptibility of diseases and the degree of responses to treatment. Thus, we aim to examine how sex influences ECM proteins and cellular behavior within the decellularized lung scaffold. Preliminary results indicate successful decellularization of the tissues with no visible nuclear material, low total protein, low collagen, and low elastin levels compared to native lung tissue. When investigating male-female specific disparities, we observe variations in sulfated glycosaminoglycan (sGAG) and elastin levels. These results imply the existence of sex-specific differences in the ECM of pig lungs. Currently, the research is focused on analyzing the structural integrity in male and female dECM using atomic force microscopy (AFM) to assess stiffness and scanning electron microscopy (SEM) to examine ultrastructure.