Alveolar Macrophage Transcriptional Programs Are Associated with Outcomes in Acute Respiratory Distress Syndrome.

Rationale: Serial measurements of alveolar macrophage (AM) transcriptional changes in patients with acute respiratory distress syndrome (ARDS) could identify cell-specific biological programs that are associated with clinical outcomes.Objectives: To determine whether AM transcriptional programs are associated with prolonged mechanical ventilation and 28-day mortality in individuals with ARDS.Methods: We performed genome-wide transcriptional profiling of AMs purified from BAL fluid collected from 35 subjects with ARDS. Cells were obtained at baseline (Day 1), Day 4, and Day 8 after ARDS onset (N = 68 total samples). We identified biological pathways that were enriched at each time point in subjects alive and extubated within 28 days after ARDS onset (alive/extubatedDay28) versus those dead or persistently supported on mechanical ventilation at Day 28 (dead/intubatedDay28).Measurements and Main Results: "M1-like" (classically activated) and proinflammatory gene sets such as IL-6/JAK/STAT5 (Janus kinase/signal transducer and activator of transcription 5) signaling were significantly enriched in AMs isolated on Day 1 in alive/extubatedDay28 versus dead/intubatedDay28 subjects. In contrast, by Day 8, many of these same proinflammatory gene sets were enriched in AMs collected from dead/intubatedDay28 compared with alive/extubatedDay28 subjects. Serially sampled alive/extubatedDay28 subjects were characterized by an AM temporal expression pattern of Day 1 enrichment of innate immune programs followed by prompt downregulation on Days 4 and 8. Dead/intubatedDay28 subjects exhibited an opposite pattern, characterized by progressive upregulation of proinflammatory programs over the course of ARDS. The relationship between AM expression profiles and 28-day clinical status was distinct in subjects with direct (pulmonary) versus indirect (extrapulmonary) ARDS.Conclusions: Clinical outcomes in ARDS are associated with highly distinct AM transcriptional programs.

Sarcoidosis and IPF in the same patient-a coincidence, an association or a phenotype?

BACKGROUND: Idiopathic Pulmonary Fibrosis (IPF) and Sarcoidosis are distinct clinical entities. Fibrotic disease in pulmonary sarcoidosis is typically upper lobe predominant. In IPF fibrosis is basilar and peripheral predominant [usual interstitial pneumonia (UIP) pattern]. Sarcoidosis and UIP have rarely been observed in the same patient. We sought to characterize patients manifesting both sarcoidosis and IPF and compare clinical features and survival to that of patients with "Lone-IPF" (IPF only) and pulmonary sarcoidosis with fibrosis in a non-UIP pattern. METHODS: Patients were identified from a clinical database and data abstracted from medical records (1995-2016): 1) 25 patients with combined sarcoidosis and IPF (CSIPF) defined by clinical and histological features of sarcoidosis and HRCT features of possible or definite UIP or UIP by histopathology; 2) Randomly selected control patients during the same period: 28 Lone-IPF, 25 stage III/IV pulmonary sarcoidosis. RESULTS: The gender and race of patients with CSIPF and Lone-IPF patients were similar (68% male and 84% Caucasian), as were survival outcomes. Mean time from IPF diagnosis to death: 3.2 years CSIPF, 3.6 years Lone-IPF (log rank p value 0.49). Among patients with pulmonary sarcoidosis, mean time from diagnosis to death: 21.4 years. CONCLUSIONS: Clinical characteristics/behavior of patients with CSIPF was similar to Lone-IPF patients. It is possible that patients with sarcoidosis coincidentally developed IPF and/or have occult genetic predisposition factors to manifest both diseases at different time points. Further study is needed.