Are DQA Antibodies Real?
Medicine, Johns Hopkins University School of Medicine, Baltimore, MD.
Meeting: 2015 American Transplant Congress
Abstract number: B245
Keywords: Epitopes, HLA antibodies, Sensitization
Session Information
Session Name: Poster Session B: Translational Genetics and Proteomics in Transplantation
Session Type: Poster Session
Date: Sunday, May 3, 2015
Session Time: 5:30pm-6:30pm
Presentation Time: 5:30pm-6:30pm
Location: Exhibit Hall E
Antibodies specific for HLA-DQ antigens appear to be increasing in frequency in the post-transplant period and are difficult to reduce effectively with desensitization protocols using plasmapheresis and IVIg. Detection of these antibodies has been greatly facilitated by the development of multiplex bead technology. DQ antibody may be specific for epitopes on the alpha chain or beta chain, or for an epitope that results from the quaternary structure of the two chains combined. We have examined 27 patients with apparent DQA antibody. We determine the specificity to be DQA when positive reactions occur with various DQB antigens bearing the same DQA and when negative reactions occur molecules having the same DQB but a different DQA. In some cases, the specificity can be further validated because the patient's phenotype contains a DQB for which there was a positive reaction. Among our 27 patients, DQA5 was the predominant specificity, occurring in nearly 52% of patients. However, this is most likely due the the frequencies of DQA1 and DQA3 antigens in 70% and 33% of patients, respectively, and only 11% with DQA5 antigen in their phenotypes. There were three patients for which there were crossmatch data two of which had serum adsorptions performed with cells bearing the relevant DQA antigen. These data are shown here.
PATIENT | SPECIFICITY | XM – unadsorbed serum | MFI – unadsorbed serum | MFI – adsorbed serum | |
RC | DQA5 | CDC>256 | 20,844 | 20,671 | |
AP | DQA5 | NEG CDC | 19,885 | ND | |
JC | DQA2 | FCXM NEG | 10,325 | 5, 706 |
To cite this abstract in AMA style:
Jones J, Lucas D, Leffell M, Zachary A. Are DQA Antibodies Real? [abstract]. Am J Transplant. 2015; 15 (suppl 3). https://atcmeetingabstracts.com/abstract/are-dqa-antibodies-real/. Accessed October 6, 2024.« Back to 2015 American Transplant Congress