title: Anti-HLA antibodies and pulmonary valve allograft function after the Ross procedure.
abstract: OBJECTIVE
  Rejection is a plausible cause of failure of allograft valves, but has not been demonstrated unequivocally in humans. A cross-sectional study has been conducted on the frequency of anti-human leukocyte antigen (HLA) antibodies in order to identify any correlation with allograft function in adult patients, following the Ross procedure.
  
  
  METHODS
  Anti-HLA antibodies were determined during regular follow up (median 1.1 years postoperatively) in a random sample of 197 patients (151 males, 46 females; mean age 46 +/- 13 years). Panel-reactive antibodies (PRA) were determined by cytotoxicity testing; anti-HLA class 2 antibodies (HLA2AB) were determined by ELISA in a subgroup of 94 patients. Echocardiographic examinations were performed during the first visit and at a median of 6.8 years postoperatively.
  
  
  RESULTS
  The prevalence of positive antibody tests was 47% for PRA and 52% for HLA2AB. A slight deterioration of allograft valve function occurred between the two examinations (median maximal pressure gradient increased from 9 mmHg to 13 mmHg, p < 0.001; median degree of regurgitation increased from zero to trivial, p = 0.020). The degree of regurgitation was slightly, but significantly, higher in PRA-positive patients at both examinations (p = 0.008 and p = 0.038). No relationship was observed between PRA status and pressure gradients, nor between HLA2AB status and allograft valve function. Neither were any other risk factors for allograft valve deterioration identified.
  
  
  CONCLUSIONS
  Subtle, clinically irrelevant and temporally stable differences with regard to regurgitation across the allograft were observed between PRA-positive and -negative patients. These findings neither proved nor disproved rejection, but rather suggested that a slow deterioration of allograft valve function was complex, and most likely multifactorial.
authors.affiliation: Department for Cardiac and Thoracic Vascular Surgery, University of Lübeck, Germany.
authors.forename: J F Matthias
authors.initials: JF
authors.lastname: Bechtel
authors.forename: Anja
authors.initials: A
authors.lastname: Marquardt
authors.forename: Michael
authors.initials: M
authors.lastname: Müller-Steinhardt
authors.forename: Thorsten
authors.initials: T
authors.lastname: Hankel
authors.forename: Ulrich
authors.initials: U
authors.lastname: Stierle
authors.forename: Hans-Hinrich
authors.initials: HH
authors.lastname: Sievers
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D003430:Cross-Sectional Studies; D004452:Echocardiography; D005260:Female; D006680:HLA Antigens / Q000276:immunology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000276:immunology*; D011312:Pressure; D011664:Pulmonary Valve / Q000000981:diagnostic imaging / Q000502:physiology / Q000637:transplantation*; D011665:Pulmonary Valve Insufficiency / Q000276:immunology*; D012086:Reoperation; D014184:Transplantation, Homologous; D055815:Young Adult
chemical_list: D006680:HLA Antigens