1. Monitoring native HLA-I trimer specific antibodies in Luminex multiplex single antigen bead assay: Evaluation of beadsets from different manufacturers
- Author
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Vadim Jucaud, Soldano Ferrone, and Mepur H. Ravindranath
- Subjects
Quality Control ,0301 basic medicine ,medicine.drug_class ,Immunology ,Peptide ,Trimer ,Human leukocyte antigen ,Monoclonal antibody ,Article ,Epitope ,Epitopes ,03 medical and health sciences ,0302 clinical medicine ,Antibody Specificity ,HLA Antigens ,Isoantibodies ,Predictive Value of Tests ,medicine ,Humans ,Immunology and Allergy ,Multiplex ,Immunoassay ,chemistry.chemical_classification ,biology ,Histocompatibility Testing ,Antibodies, Monoclonal ,Reproducibility of Results ,Molecular biology ,Histocompatibility ,030104 developmental biology ,chemistry ,Immunoglobulin G ,biology.protein ,Antibody ,030215 immunology - Abstract
Luminex single antigen bead (SAB) assay utilizes beadsets coated with a set of cloned and purified HLA molecules, for monitoring serum anti-HLA antibodies. Particularly, the level of serum IgG against native HLA-I trimers (heavy chain (HC) and β2-microglobulin (β2 m) with a peptide), expressed in allograft tissues is correlated with graft failure. In addition to native trimeric HLA–I, the beadsets may carry HC only or the dimeric variants, peptide-free HC with β2 m and β2 m–free HC with or without peptides. Currently, three different HLA-I coated beadsets have been produced commercially. The HLA antigen density on one beadset was reported to be approximately 50% of that present on another beadset as evidenced by the binding of an anti-HLA-I mAb W6/32. To date, no efforts have been made to compare the relative distribution of HLA-I variants in these three beadsets. In this study, using monoclonal antibodies (W6/32, HC-10 and TFL-006) that can distinguish the structural variants based on their epitope specificities, the nature of the variants in the three beadsets were comparatively evaluated. One beadset (Beadset A, see Materials and methods for Brand and Manufacturer’s names) (W6/32+/HC-10+/TFL-006+) carried at least three variants, while beadset B (W6/32+/HC-10+/TFL-006−) carried two (peptide-associated and peptide-free β2 m–HC) and the beadset C (W6/32+/HC-10−/TFL-006−) carried exclusively the HLA-I trimer suggesting its usefulness for specific monitoring native HLA-I trimer antibodies. Because of the salient differences in the variants coated on the different beadsets, it would be warranted to investigate, if these differences are clinically relevant for monitoring serum anti-HLA antibodies in sensitized patients waiting for donor organs and in allograft recipients (274).
- Published
- 2017
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