Genetic Strategies for Labeling AT2 Cells in Murine Lung via Abca3 and Etv5-Driven Reporters

Abstract

Precise labeling of alveolar type 2 (AT2) cells is essential for elucidating lung development and injury responses. In this study, we evaluated Abca3 and Etv5-based genetic strategies for labeling AT2 cells in murine models. Using targeted genetic approaches, we generated Abca3-rtTA and Etv5-rtTA knock-in mouse lines and crossed them with pTRE-H2BGFP to create inducible reporter models driven by Abca3 or Etv5. Labeling specificity and efficiency were assessed by flow cytometry and co-immunostaining. Our results show that both Abca3 and Etv5 strategies faithfully label AT2 cells across developmental stages and following lung injury. Comprehensive analyses confirmed the high specificity and efficiency of labeling. These Abca3- and Etv5-driven systems offer robust tools for investigating AT2 cell biology and pathology and may serve as effective drivers for tetO-mediated gene knockout or overexpression studies specifically in AT2 cells in mouse models.

Keywords

Alveolar type 2 (AT2) cells / Abca3 / Etv5 / Lung development / Bleomycin injury

Acknowledgments

The authors thank the lab members for their support and discussion during the study.

Statement of the Use of Generative AI and AI-Assisted Technologies in the Writing Process

During the preparation of this manuscript, the authors used ChatGTP for language proofreading. After using this tool, the authors reviewed and edited the content as needed and take full responsibility for the content of the published article.

Author Contributions

X.L. and D.J. conceived the study. X.L., X.Z. and J.L. designed and analyzed the data. X.L., Z.L., V.K. and N.L. performed data analysis and interpretation. X.L. and D.J. wrote the paper.

Ethics Statement

All animal experiments in this study were conducted with the approval of the Cedars-Sinai Medical Center Institutional Animal Care and Use Committee (IACUC #008529, approveal date: 26 February 2019).

Informed Consent Statement

Not applicable.

Data Availability Statement

Mouse lines generated in this study will be deposited to the Mutant Mouse Resource & Research Centers (MMRRC) and will be made available on request by contacting the corresponding author ([e-mail]).

Funding

This work was funded by National Institutes of Health grants R01-HL172990 (D.J.), R01-AG078655 (J.L.), American Heart Association Career Development Award 24CDA1268568 (X.L.) and Pulmonary Fibrosis Foundation PFF Scholars Program 1272558 (X.L.).

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

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