OBJECTIVETo evaluate the safety and effectiveness of a novel therapeutic regimen for bronchiolitis obliterans sydrome (BOS) affter hematopoietic stem cell transplantation (HSCT).

METHODSSeven patients who had received HSCT and had been diagnosed as BOS were enrolled in this study. They received weekly intravenous injection of umbilical cord-derived mesenchymal stem cells (MSC) at a dose of 1 × 10(6)/kg for 4 weeks. Budesonide was given orally at a daily dose of 0.25 g, and salmeterol was inhaled at a dose of 4.5 µg for 3 times per day. Methylprednisolone was given at a dose of 1 mg/(kg·d) for 2 weeks when respiratory failure occured. The dose of methylprednisolone was tapered to 0.25 mg/(kg·d) after 4 weeks and was adjusted according to the occurrence and severity of chronic graft-versus-host disease (cGVHD).

RESULTSThe therapy was generally safe and no severe acute toxicity was observed. One patient died of heart failure during the treatment, the other 6 patients were alive and the pulmonary function parameters including FEV1, FEV1/FVC, PaO2 and AaDO2 were significantly improved after 6 months as compared with the baseline parameters (P < 0.05).

CONCLUSIONMSC combined with budesonide, almeterol and azithromycin has been confirmed to be generally safe and can reduce the dose of glucocorticoid in treatment of BOS after HSCT.