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

## TL;DR

This study develops new genetic tools to label alveolar type 2 cells in mouse lungs for better understanding of lung biology and disease.

## Contribution

The novel contribution is the development of Abca3- and Etv5-driven inducible reporter systems for precise labeling of AT2 cells.

## Key findings

- Abca3 and Etv5 strategies effectively label AT2 cells across developmental stages.
- Both methods show high specificity and efficiency confirmed by flow cytometry and immunostaining.
- The systems can be used for tetO-mediated gene manipulation in AT2 cells.

## 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.