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Background: Donor lungs are often discarded, with gastric aspiration accounting for ~9% of lungs unsuitable for transplantation. To increase the donor pool, it is important to understand the pathophysiology of aspiration-induced lung damage (AILD) and to assess its treatment. Methods: Precision-cut lung slices (PCLS) were prepared from murine lungs and exposed to acid—pH 1.5 to 5.5—for 15 min. We also investigated whether acid-exposed slices (pH 3.5) could affect unexposed slices. In addition, we investigated whether dexamethasone (0.5 or 1 μM) could mitigate and treat the damage in each group. In each experiment (n = 3), we analyzed cell viability (ATP/protein content) and markers of inflammation (IL-1β, IL-6, TNF-𝛼, TRAIL). Results: PCLS subjected to pH 1.5–3.5 had a significantly reduced amount of ATP, albeit no increase in inflammation markers. There was no interaction of secretions from acid-exposed slices on unexposed slices. Dexamethasone had no beneficial effects in either group. Conclusion: Direct exposure to acid in the PCLS leads to a decrease in cell viability. Acid-exposed slices had no effect on the cell viability of unexposed slices. Treatment with dexamethasone offered no mitigation. More studies have to be performed to elucidate the pathophysiology of AILD and the possible treatment of aspiration-induced injury.

Circulatory death donor (DCD) kidneys are increasingly used to enlarge the donor pool. These kidneys undergo ischemia-reperfusion injury, frequently leading to renal fibrosis. Transforming growth factor beta 1 (TGF-β1) and matrix metalloproteases have been identified as central mediators of fibrosis and inhibition of these targets could attenuate fibrosis. We studied whether galunisertib, doxycycline, taurine, and febuxostat alleviated fibrosis in precision-cut kidney slices (PCKS). PCKS were prepared from porcine kidneys that were exposed to 30 min of warm ischemia followed by 3 h of oxygenated hypothermic machine perfusion. We subsequently incubated PCKS for 48 h at 37 °C with the described compounds. To further elucidate the antifibrotic effects of galunisertib, we cultured PCKS with TGF-β1. We first screened the effects of the compounds without TGF-β1. Most significant effects were observed for galunisertib which lowered the expression of ACTA2, TGFB1, FN2, and SERPINE1. We then investigated the effects of galunisertib in fibrotic PCKS incubated with TGF-β1. TGF-β1 significantly increased expression of TGFB1, FN1, SERPINE1, and SERPINH1. Galunisertib, however, attenuated the expression of all fibrosis-related genes. Galunisertib appears to be a promising antifibrotic compound requiring further research in a preclinical model and may ultimately be administered during machine perfusion as an antifibrotic treatment in a transplant setting.