Interferon-γ selectively promotes survival of alveolar progenitor cells in a human lung organoid model.

Abstract

Disease of the lung alveoli is frequently associated with acute or chronic inflammation. At present, there are no effective therapies to support regeneration of the alveolar epithelium, and ongoing inflammation adds an additional layer of complexity to many lung diseases. Here, we describe a primary adult human organoid model for investigating how inflammation shapes alveolar regeneration. Unlike previous models, this system supports long-term expansion of newly identified human-specific alveolar progenitor cells and serum-free differentiation into alveolar type 1 (AT1)-like cells. Using this platform, we find that interferon-gamma (IFN-γ) exerts cytotoxic effects on mature AT1-like cells while promoting survival of alveolar progenitor cells mediated by BIRC3. This unexpected selective positive effect of IFN-γ on alveolar progenitors underscores the need for nuanced and context-dependent evaluation of the influence of pro-inflammatory cytokines on alveolar regeneration. Our organoid model provides a reductionist platform for mechanistic studies and discovery of strategies to enhance alveolar regeneration.