The American Journal of Transplantation study reports a T-cell-derived small extracellular vesicle (sEV) platform that distinguished acute cellular rejection in mouse lung transplant models and a human cohort of just 20 bilateral recipients sampled at days 1, 3, and 30. This observational design, not an RCT, showed profile shifts correlating with biopsy findings yet lacked power analysis, blinding, or external validation. Prior work by the same Yale group on heart transplants (n=30) demonstrated analogous T-cell sEV changes, suggesting cross-organ biology, but lung data remain preliminary. Broader literature, including ISHLT registry analyses (n>20,000), links untreated ACR to bronchiolitis obliterans syndrome; reducing surveillance biopsies could lower pneumothorax rates (5-15% in observational series). However, the reported <1% T-cell sEV fraction in plasma raises reproducibility concerns without standardized enrichment protocols. Conflicts of interest were not disclosed in the press coverage. Larger multicenter trials are essential before replacing invasive monitoring.