CD11b immunophenotyping identifies inflammatory profiles in the mouse and human lungs.

Area of Science:

• Immunology
• Pulmonology
• Cell Biology

Background:

• Personalized therapy for inflammatory lung diseases requires tools to classify patients by disease endotypes.
• Current methods lack a systematic approach for studying complex and heterogeneous lung disease etiologies.

Purpose of the Study:

• To develop a standardized flow cytometry approach for identifying parallel inflammatory alveolar macrophage phenotypes in mouse and human lungs.
• To enable endotyping of inflammatory lung diseases for improved patient classification and therapy.

Main Methods:

• Developed an internally standardized flow cytometry protocol.
• Analyzed innate immune cell alterations in mouse models (endotoxin challenge, influenza, COPD models).
• Investigated alveolar macrophage CD11b expression and lung eosinophilia in disease states.

Main Results:

• Successfully segregated lung innate immune cell alterations in mice based on CD11b alveolar macrophage upregulation and eosinophilia.
• Identified heightened alveolar macrophage CD11b expression as a feature of acute lung exacerbations in a COPD model.
• Demonstrated selective blockade of inflammatory CD11b(pos) alveolar macrophages using anti-CD11b antibody in vivo.
• Observed analogous macrophage profiles in human respiratory disease patients.

Conclusions:

• The standardized flow cytometry approach provides a translational method for lung disease endotyping.
• Heterogeneous innate immune cell phenotypes are a significant, underappreciated factor in the human lung disease microenvironment.
• This method advances personalized medicine for inflammatory lung conditions.