An animal model of severe acute respiratory distress syndrome for translational research.

Summary

The authors established a reproducible, severe unilateral (left-lobe) ARDS rat model by intratracheal bleomycin (5 mg/rat) with 60° leftward rotation. The model preserves survival, mirrors clinical ARDS physiology, and is designed for rigorous testing of cell-based and pharmacologic therapies.

Key Findings

• Intratracheal bleomycin at 5 mg/rat delivered to the left trachea with 60° leftward rotation produced a severe, stable, unilateral ARDS phenotype.
• Physiological features in this model were reported to be entirely consistent with clinical ARDS.
• The model preserves animal survival and demonstrated consistent reproducibility, enabling rigorous testing of stem cell and drug therapies.

Clinical Implications

While preclinical, the model can improve the predictive value of preclinical efficacy screens for ARDS therapeutics and ventilatory strategies before human trials.

Limitations

• Bleomycin-induced injury may not capture the heterogeneity and multifactorial nature of human ARDS
• Unilateral (left-lobe) injury may differ from diffuse bilateral involvement seen clinically

Future Directions

Use the model to benchmark stem cell therapies, anti-inflammatory drugs, and ventilatory strategies; validate in other species and bilateral/diffuse variants; add standardized outcome measures.