Donor specific HLA antibodies (DSA) have been associated with poor outcomes after lung transplantation including bronchiolitis obliterans (BOS). We sought to evaluate the relationship between DSA, freedom from BOS and survival in a cohort of consecutive lung transplant recipients who received induction with alemtuzumab.A cross-sectional study of patients from 2003-2007 was performed. Per protocol, patients were screened at 2 weeks and every 3 months for class I and II DSA with ELISA and Luminex-based assays in conjunction with surveillance and clinical bronchoscopies. The primary outcome was time from transplant to the development of BOS or death with a study endpoint of 9/1/2010. Associations were assessed with student t-tests and freedom from BOS and survival were assessed with Kaplan Meier estimates with log rank analysis.A total of 343 patients were included with a mean follow-up time of 3.3 ± 1.9 years. 51 (14.8%) patients developed DSA at a median time of 435 (IQR 697) days from transplantation. 41 (80.4%) patients with DSA developed BOS during the study period versus 79 (27.1%) of patients without DSA. The mean onset to BOS in patients with DSA was 787.5 (SD 390) days versus 978.3 (SD 532) days in those patients without DSA (p <0.05). Patients with DSA also had a higher mortality than patients without DSA at study end (54.9% vs. 32.1%; p=0.004).After induction with alemtuzumab, the incidence of DSA in lung transplant recipients is lower in comparison with previous reports. Patients with DSA are at a higher risk of early BOS and mortality. Further studies are needed to assess the significance of antibody-directed therapy to improve allograft function and overall survival.