Alveolar epithelial type 2 cells in acute lung injury and acute respiratory distress syndrome: spatiotemporal fate and regulation

Abstract

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) present significant challenges in critical care, with high mortality rates and limited treatment options. Alveolar epithelial type 2 (AT2) cells are central to lung repair and regeneration and play a vital role in maintaining lung homeostasis. However, the regulatory mechanisms governing AT2 cell fate during different stages of lung injury and repair remain incompletely understood. This review delves into the temporal and spatial heterogeneity of AT2 cells, highlighting their dynamic behavior in response to lung injury. We explore the pivotal role of AT2 cells across various stages of inflammation, repair, and fibrosis and discuss how these processes are influenced by factors such as aging, mechanical stress, and interactions within the alveolar microenvironment. This review also emphasizes the importance of integrating spatiotemporal multiomics approaches to uncover the molecular mechanisms underlying AT2 cell function and their potential therapeutic applications. Furthermore, we discuss novel strategies for enhancing the regenerative capacity of AT2 cells through targeted delivery systems, including protein, gene, and mitochondrial therapies. By advancing our understanding of AT2 cell biology and improving therapeutic approaches, we aim to pave the way for more effective treatments for lung injury diseases, particularly ALI and ARDS.

Keywords

Acute lung injury / Acute respiratory distress syndrome / Alveolar epithelial type 2 cells / Lung regeneration / Spatiotemporal multiomics / Alveolar epithelial type 2 cell fate / Targeted therapy

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