title: Impact of alloantibody strength in crossmatch negative DSA positive kidney transplantation.
abstract: OBJECTIVE
  The clinical relevance of pre-transplant "low-level" donor specific anti-HLA antibodies (DSAs) in crossmatch negative kidney transplant recipients remains unclear. To determine what level of DSA associates with antibody mediated rejection (AMR) could be the way to measure the clinical relevance of pre-transplant "low-level" donor specific anti-HLA antibodies (DSAs) in crossmatch negative kidney transplant recipients.
  
  
  METHODS
  A retrospective analysis of 221 patients from October 2008 to December 2009 was included in this study. Sera were obtained pre-transplant and two weeks post-transplant and tested for DSA using LABScreen single antigen beads.
  
  
  RESULTS
  Among the 221 patients, 11 experienced AMR within 200days after transplant (5%). Pre-transplant DSA was associated with AMR at multiple mean fluorescence intensity (MFI) cutoffs (500, 1000, 2000, 3000, 5000; p=0.003, 0.001, 0.007, 0.003, and 0.003, respectively). No correlation was seen between acute T-cell mediated rejection (CMR) and pre-transplant DSA at any of the same MFI cutoffs. There was an increased risk of AMR with higher levels of pre-transplant DSA. Finally, an increase in DSA MFI from pre- to two weeks post-transplant was indicative of a higher probability of AMR.
  
  
  CONCLUSIONS
  Overall, this data supports using the single antigen bead to detect "low-level" DSA both pre- and post- as having a positive and persistent DSA may be predictive of higher AMR rates and poorer graft survival.
authors.affiliation: Kidney Disease Center, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, PR China; Kidney Disease Immunology Laboratory, The Third Grade Laboratory, State Administration of Traditional Chinese Medicine of the People's Republic of China, PR China; Key Laboratory of Zhejiang Province, PR China.
authors.forename: Pingping
authors.initials: P
authors.lastname: Wu
authors.forename: Juan
authors.initials: J
authors.lastname: Jin
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Everly
authors.forename: Chuan
authors.initials: C
authors.lastname: Lin
authors.forename: Paul I
authors.initials: PI
authors.lastname: Terasaki
authors.forename: Jianghua
authors.initials: J
authors.lastname: Chen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000915:Antibody Affinity; D015415:Biomarkers / Q000378:metabolism; D005260:Female; D006084:Graft Rejection / Q000097:blood* / Q000175:diagnosis* / Q000276:immunology; D006085:Graft Survival; D006680:HLA Antigens / Q000276:immunology*; D006650:Histocompatibility Testing; D006801:Humans; D007518:Isoantibodies / Q000097:blood* / Q000276:immunology; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D013601:T-Lymphocytes / Q000201:enzymology* / Q000473:pathology; D014019:Tissue Donors
chemical_list: D015415:Biomarkers; D006680:HLA Antigens; D007518:Isoantibodies
keywords: AMR; Anti-HLA antibodies; Antibody Mediated Rejection; Antibody-mediated rejection; CDC-XM; CMR; Cell Mediated Rejection; Complement Dependent Cytotoxicity Crossmatch; DSA; Donor Specific Antibody; Donor-specific antibodies; FXM; Flow Crossmatch; Kidney transplantation; MFI; Mean Fluorescence Intensity; PTC; Peritubular Capillaries; SAFB; Single Antigen Flow Bead