title: Relationship of HLA-DQA1 alleles and humoral antibody following measles vaccination.
abstract: BACKGROUND
  The human leukocyte antigen (HLA)-DQA1 locus is only moderately polymorphic compared to other HLA class II loci; however, we hypothesized that these polymorphisms could be important in determining the humoral antibody response to measles vaccine virus.
  
  
  METHODS
  The seroprevalence of measles antibody was determined in 881 school children who had been immunized with MMR-II at age approximately 15 months. All subjects resided in a geographic area with no circulating measles virus. The IgG antibody levels were determined by a measles-specific whole virus enzyme immunoassay (EIA) (BioWhittaker, Walkersville, MD). Subjects who were nonresponders (IgG seronegative or equivocal) (n = 46) and hyperresponders (upper 10th percentile of IgG levels of all subjects) (n = 64) were HLA-DQA1 typed using polymerase chain reaction with sequence-specific primers (PCR-SSP). The HLA-DQA1 allele frequencies, as well as homozygosity rates, were compared between the nonresponders and hyperresponders.
  
  
  RESULTS
  The overall allele frequency distribution of alleles between the nonresponders and hyperresponders was significantly different (P = 0.05), with nonresponders having an excess of HLA-DQA1*05 alleles (P = 0.017) and hyperresponders having an excess of HLA-DQA1*01 alleles (P = 0. 016). The homozygosity rate among nonresponders was significantly higher than among hyperresponders (23.9% vs. 9.4%, P = 0.037).
  
  
  CONCLUSIONS
  HLA-DQA1 alleles have important associations with the antibody response to measles vaccine. Specifically, the carriage of the HLA-DQA1*05 alleles is associated with nonresponse and that of HLA-DQA1*01 alleles with hyperresponse. In addition, HLA-DQA1 homozygosity is significantly associated with poor antibody response to measles vaccine.
authors.affiliation: Mayo Vaccine Research Group, Clinical Pharmacology Unit, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA.
authors.forename: M S
authors.initials: MS
authors.lastname: Hayney
authors.forename: G A
authors.initials: GA
authors.lastname: Poland
authors.forename: R M
authors.initials: RM
authors.lastname: Jacobson
authors.forename: D
authors.initials: D
authors.lastname: Rabe
authors.forename: D J
authors.initials: DJ
authors.lastname: Schaid
authors.forename: S J
authors.initials: SJ
authors.lastname: Jacobsen
authors.forename: J J
authors.initials: JJ
authors.lastname: Lipsky
mesh_terms: D000293:Adolescent; D000483:Alleles; D000914:Antibodies, Viral / Q000096:biosynthesis* / Q000276:immunology; D000917:Antibody Formation / Q000235:genetics; D002648:Child; D002675:Child, Preschool; D005260:Female; D005787:Gene Frequency; D006683:HLA-DQ Antigens / Q000235:genetics* / Q000276:immunology; D006650:Histocompatibility Testing; D006720:Homozygote; D006801:Humans; D007124:Immunoenzyme Techniques; D007074:Immunoglobulin G / Q000276:immunology; D007223:Infant; D008297:Male; D008458:Measles Vaccine / Q000276:immunology*; D016133:Polymerase Chain Reaction; D014611:Vaccination
chemical_list: D000914:Antibodies, Viral; D006683:HLA-DQ Antigens; D007074:Immunoglobulin G; D008458:Measles Vaccine