The neutrophil alloantigen HNA-3a (5b) is located on choline transporter-like protein 2 and appears to be encoded by an R>Q154 amino acid substitution.
The molecular basis of the HNA-3a/b (5b/a) leukocyte antigen system has not yet been defined despite evidence that HNA-3a-specific antibodies are particularly prone to cause severe, often fatal, transfusion-related lung injury. We used genome-wide single nucleotide polymorphism scanning and sequencing of DNA from persons of different HNA-3a/b phenotypes to identify a single single nucleotide polymorphism in exon 7 of the CLT2 gene (SLC44A2) that predicts an amino acid substitution in the first extracellular loop of choline transporter-like protein 2, a member of the choline transporter-like protein family of membrane glycoproteins, and correlates perfectly with HNA-3a/b phenotypes (R154 encodes HNA-3a; Q154 encodes HNA-3b). Mass spectrometric analysis of proteins immunoprecipitated from leukocytes by anti-HNA-3a provided direct evidence that anti-HNA-3a recognizes choline transporter-like protein 2. These findings will enable large-scale genotyping for HNA-3a/b to identify blood donors at risk to have HNA-3a-specific antibodies and should facilitate development of practical methods to detect such antibodies and prevent transfusion-related lung injury.
Curtis
Brian R
BR
Platelet & Neutrophil Immunology Laboratory, BloodCenter of Wisconsin, PO Box 2178, Milwaukee, WI 53201-2178, USA. brian.curtis@bcw.edu
Cox
Nancy J
NJ
Sullivan
Mia J
MJ
Konkashbaev
Anuar
A
Bowens
Krista
K
Hansen
Kirk
K
Aster
Richard H
RH
D000595:Amino Acid Sequence; D019943:Amino Acid Substitution / Q000235:genetics / Q000502:physiology; D001120:Arginine / Q000235:genetics; D001483:Base Sequence; D004252:DNA Mutational Analysis; D055106:Genome-Wide Association Study; D018698:Glutamic Acid / Q000235:genetics; D006801:Humans; D007519:Isoantigens / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D013058:Mass Spectrometry; D008562:Membrane Glycoproteins / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D026901:Membrane Transport Proteins / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D008969:Molecular Sequence Data; D050505:Mutant Proteins / Q000276:immunology / Q000378:metabolism; D009504:Neutrophils / Q000276:immunology* / Q000378:metabolism*; D020641:Polymorphism, Single Nucleotide / Q000502:physiology
C518134:HNA-3a antigen, human; D007519:Isoantigens; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D050505:Mutant Proteins; C484524:SLC44A2 protein, human; D018698:Glutamic Acid; D001120:Arginine