Novel bronchoscopic treatment for bronchopleural fistula using adipose-derived stromal cells.

BACKGROUND AIMS: In this report, we describe the successful bronchoscopic management of bronchopleural fistula in two patients, using autologous adipose-derived stromal cells. Cell therapy was considered for 2 cases of bronchopleural fistula refractory to conventional surgical treatment after control of the primary disease was confirmed and active pleural infection was ruled out. Briefly, adipose-derived stem cells were first isolated from lipoaspirate and used without cell expansion. In 24 months, we have not received more patients with bronchopleural fistula in our hospital and we have not been able to include more patients. METHODS: Briefly, adipose-derived stem cells were first isolated from lipo-aspirate and used without cell expansion. A bronchopleural fistula was identified through bronchoscopy, and the mucosa surrounding the fistula was ablated with an argon plasma coagulator. Isolated stem cells were then endoscopically injected into the de-epithelialized area and fistulous tract. If an open thoracostomy was present at the time of the intervention, the same procedure was performed on the pleural side. Bronchoscopic follow-up was scheduled weekly during the first month, monthly during the first year, and then yearly. The underlying etiologies were left pneumonectomy and right lower video-assisted lobectomy for non-small-cell lung cancer. The sizes of the fistulas were 6 mm and 3 mm in diameter, respectively. RESULTS: Both patients were discharged on the first postoperative day. The 3-year follow-up revealed a successful and maintained fistula closure, no treatment-related adverse reactions, nonlocal malignant recurrence and improved quality of life. CONCLUSIONS: This preliminary study showed that bronchoscopic application of autologous adipose-derived stem cells is a feasible, safe and effective procedure for treating bronchopleural fistula.

Cytosolic phospholipase A2 inhibition attenuates ischemia-reperfusion injury in an isolated rat lung model.

BACKGROUND: Arachidonic acid metabolites and platelet-activating factor (PAF) are potentially involved in ischemia-reperfusion (IR) lung injury. A key enzyme regulating their metabolism is cytosolic phospholipase A2 (cPLA2). Arachidonyl trifluoromethyl ketone (AACOCF3) is reported to be a potent cPLA2 inhibitor. In the present study, we hypothesized that pharmacological inhibition of cPLA2 might ameliorate IR lung injury. METHODS: To test the hypothesis, we examined the effects of AACOCF3 in an isolated rat lung model. Three groups were defined (n=6, each): in the vehicle group, lungs were perfused for 2 hours without an ischemic period. In the ischemic groups, 20 mg/kg of AACOCF3 (AACOCF3 group) or saline (control group) was i.v. administered 15 min before lung harvest. Lungs were flushed with LPD solution, cold-stored 18 hours, and reperfused for 2 hours. RESULTS: IR increased cPLA2 activity mainly via alveolar macrophages, sPLA2 activity, thromboxane and leukotriene formation, and the expression of PAF receptor, whereas AACOCF3 treatment significantly reduced all of these. Compared to the vehicle group, the wet-to-dry ratio, proteins in BAL, and MPO activity increased significantly by twofold, fourfold, and threefold, respectively. Furthermore, the PO2 dropped from 615.7+/-31.2 to 452.1+/-30.9 mmHg at the end of reperfusion (P<0.001). AACOCF3 treatment maintained the PO2 at a level similar to the vehicle group throughout reperfusion and reduced significantly the alveolar-capillary leakage, edema formation, and neutrophil extravasation. CONCLUSION: Pharmacological inhibition of the cPLA2 cascade decreases bioactive lipid formation and attenuates IR-induced lung injury.