Multidimensional assessment of alveolar T cells in critically ill patients

Area of Science:

• Immunology
• Genomics
• Infectious Diseases

Background:

• Pneumonia is a leading infectious cause of death.
• T cell responses are critical in pneumonia but difficult to study in patients.
• Existing methods limit detailed molecular analysis of T cells from lung airspaces.

Purpose of the Study:

• To develop and validate a safe, high-resolution method for profiling T cell subsets from the alveoli of critically ill pneumonia patients.
• To enable detailed transcriptional and epigenetic analysis of T cells in human pneumonia.
• To bridge findings from mouse models to human disease biology.

Main Methods:

• Nonbronchoscopic bronchoalveolar lavage for safe T cell collection.
• Multiparameter fluorescence-activated cell sorting for T cell subset isolation.
• Unsupervised low-input RNA-sequencing and modified reduced-representation bisulfite sequencing for genomic profiling.

Main Results:

• Demonstrated the safety and feasibility of the novel T cell profiling method.
• Successfully performed high-resolution transcriptional and DNA methylation profiling on small T cell samples from alveoli.
• Validated functional genomic elements predicted by mouse models in human pneumonia.

Conclusions:

• The developed method provides unprecedented insights into human pneumonia biology.
• This technique allows detailed characterization of T cell function in critically ill patients.
• The approach has potential for widespread application in studying lung infections and other diseases.