HNA-3a-specific antibodies recognize choline transporter-like protein-2 peptides containing arginine, but not glutamine at Position 154

• Published in: Transfusion (Philadelphia, Pa.) Vol. 51; no. 10; pp. 2168 - 2174
• Main Authors: Curtis, Brian R., Sullivan, Mia J., Holyst, M. Trudy, Szabo, Aniko, Bougie, Daniel W., Aster, Richard H.
• Format: Journal Article
• Language: English
• Published: Malden, USA Blackwell Publishing Inc 01-10-2011; Wiley
• Subjects: Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Arginine - chemistry; Biological and medical sciences; Blood Transfusion; Blood. Blood and plasma substitutes. Blood products. Blood cells. Blood typing. Plasmapheresis. Apheresis; Emergency and intensive care: metabolism and nutrition disorders. Enteral and parenteral nutrition; Enzyme-Linked Immunosorbent Assay; Epitope Mapping; Epitopes; Glutamine - chemistry; Humans; Intensive care medicine; Isoantibodies - chemistry; Isoantibodies - immunology; Isoantigens - immunology; Medical sciences; Membrane Glycoproteins - chemical synthesis; Membrane Glycoproteins - chemistry; Membrane Glycoproteins - immunology; Membrane Transport Proteins - chemical synthesis; Membrane Transport Proteins - chemistry; Membrane Transport Proteins - immunology; Transfusions. Complications. Transfusion reactions. Cell and gene therapy; Choleretic; Transfusion; Arginine; Aminoacid; Choline; Glutamine
• ISSN: 0041-1132; 1537-2995
• DOI: 10.1111/j.1537-2995.2011.03145.x

BACKGROUND: Antibodies specific for the neutrophil antigen HNA‐3a cause severe, sometimes fatal transfusion‐related acute lung disease (TRALI) when transfused, but it has not been possible to screen blood donors for anti‐HNA‐3a because using neutrophils as targets was impractical and molecular properties of the antigen were unknown. Recently it was shown that HNA‐3a is carried on choline transporter–like protein‐2 (CTL2) and that the HNA‐3a/b phenotype is closely correlated with an R154Q amino acid polymorphism in CTL2. However, it has not been shown by direct experiment that R154 is essential for the HNA‐3a epitope.
STUDY DESIGN AND METHODS: Preliminary attempts to express recombinant full‐length CTL2 (R154) recognized by anti‐HNA‐3a were unsuccessful. We therefore tested HNA‐3a–specific antibodies from donors implicated in TRALI reactions for reactivity against chemically synthesized linear and cyclic CTL2 peptides containing R154 or Q154.
RESULTS: Nine of 20 HNA‐3a antibodies recognized the R154, but not the Q154 version of a cyclic 36‐residue CTL2 peptide (D131‐K166). However, 11 others failed to distinguish between the two versions of this peptide.
CONCLUSION: The findings provide direct evidence that R154 in the context of CTL2 D131‐K166 is necessary to create the HNA‐3a epitope but, in the context of cyclic CTL2 peptide D131‐K166, is sufficient to detect only about one‐half of the HNA‐3a–specific antibodies implicated in TRALI. It is likely that fragments of CTL2 longer than can be made on a large scale with an automated synthesizer will be needed to produce a target capable of detecting all examples of anti‐HNA‐3a in donated blood.