Interstitial Macrophages Mediate Efferocytosis of Alveolar Epithelium during Influenza Infection

Efferocytosis is a process whereby apoptotic cells are cleared to maintain tissue homeostasis. In the lungs, efferocytosis has been implicated in several acute and chronic inflammatory diseases. A long-standing method to study efferocytosis in vivo is to instill apoptotic cells into the lungs to evaluate macrophage uptake. However, this approach provides nonphysiologic levels of cells to the airspaces, where there is preferential access to the alveolar macrophages. To circumvent this limitation, we developed a new method to study efferocytosis of damaged alveolar type 2 (AT2) epithelial cells in vivo. A reporter mouse that expresses TdTomato in AT2 epithelial cells was injured with influenza (strain PR8) to induce apoptosis of AT2 cells. We were able to identify macrophages that acquire red fluorescence after influenza injury, indicating efferocytosis of AT2 cells. Furthermore, evaluation of macrophage populations led to the surprising finding that lung interstitial macrophages were the primary efferocyte in vivo. In summary, we present a novel finding that the interstitial macrophage, not the alveolar macrophage, primarily mediates clearance of AT2 cells in the lungs after influenza infection. Our method of studying efferocytosis provides a more physiologic approach in evaluating the spatiotemporal dynamics of apoptotic cell clearance in vivo and opens new avenues to study the mechanisms by which efferocytosis regulates inflammation.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:70

Enthalten in:

American journal of respiratory cell and molecular biology - 70(2024), 3 vom: 29. März, Seite 159-164

Sprache:

Englisch

Beteiligte Personen:

Zuttion, Marilia Sanchez Santos Rizzo [VerfasserIn]
Parimon, Tanyalak [VerfasserIn]
Yao, Changfu [VerfasserIn]
Stripp, Barry R [VerfasserIn]
Wang, Ying [VerfasserIn]
Soto, Christopher M [VerfasserIn]
Ortega, Zackary [VerfasserIn]
Li, Xiao [VerfasserIn]
Janssen, William J [VerfasserIn]
Chen, Peter [VerfasserIn]

Links:

Volltext

Themen:

Apoptosis
Efferocytosis
Influenza
Journal Article
Lung inflammation
Red Fluorescent Protein
TdTomato

Anmerkungen:

Date Completed 04.03.2024

Date Revised 20.03.2024

published: Print

Citation Status MEDLINE

doi:

10.1165/rcmb.2023-0217MA

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM366977032