title: Antibodies to HLA-E in nonalloimmunized males: pattern of HLA-Ia reactivity of anti-HLA-E-positive sera.
abstract: Natural anti-HLA Abs found in sera of healthy nonalloimmunized males recognize HLA-Ia alleles parallel to those recognized by anti-HLA-E mAbs (MEM-E/02/06/07). Therefore, some of the HLA-Ia Abs seen in healthy males could be due to anti-HLA-E Abs cross-reacting with HLA-Ia. If anti-HLA-E Abs occur in healthy nonalloimmunized males, it can be assessed whether they evoke HLA-Ia reactivity as do mouse HLA-E mAbs. IgG and IgM Abs to HLA-E and HLA-Ia alleles are identified in sera of healthy males using microbeads coated with recombinant denatured HLA-E or a panel of rHLA-Ia alleles. The pattern of allelic recognition is comparable to that of anti-HLA-E mAbs. Sixty-six percent of the sera with HLA-E IgG have a high level of HLA-Ia IgG, whereas 70% of those with no anti-HLA-E Abs have no HLA-Ia Abs. HLA-E IgM/IgG ratios of sera are divided into four groups: IgM(Low)/IgG(Low), IgM(High)/IgG(Low), IgM(High)/IgG(High), and IgM(Low)/IgG(High). These groups correspond to anti-HLA-Ia IgM/IgG ratio groups. When HLA-E IgM and IgG are absent or present in males, the IgM or IgG of HLA-Ia are similarly absent or present. The mean fluorescent intensity of HLA-Ia Abs correlates with that of anti-HLA-E Abs. Most importantly, HLA-E and HLA-Ia reactivities of the sera are inhibited by the shared, but cryptic, peptide sequences (117)AYDGKDY(123) and (137)DTAAQIS(143). Therefore, Abs to the H chain of HLA-E may be responsible for some of the HLA-Ia allele reactivity of the natural HLA-Ia Ab in human sera. Absence of any anti-HLA-Ia Abs in 112 nonvegans and the presence of the same in vegans suggest that dietary meat proteins might not have induced the natural allo-HLA Abs.
authors.affiliation: Terasaki Foundation Laboratory, Los Angeles, CA 90064, USA. glycoimmune@terasakilab.org
authors.forename: Mepur H
authors.initials: MH
authors.lastname: Ravindranath
authors.forename: Hugo
authors.initials: H
authors.lastname: Kaneku
authors.forename: Nadim
authors.initials: N
authors.lastname: El-Awar
authors.forename: Luis E
authors.initials: LE
authors.lastname: Morales-Buenrostro
authors.forename: Paul I
authors.initials: PI
authors.lastname: Terasaki
mesh_terms: D000328:Adult; D000483:Alleles; D000818:Animals; D000911:Antibodies, Monoclonal / Q000378:metabolism; D000915:Antibody Affinity; D001324:Autoantigens / Q000276:immunology; D001666:Binding Sites, Antibody; D003429:Cross Reactions; D005260:Female; D006680:HLA Antigens / Q000097:blood / Q000235:genetics / Q000276:immunology*; D015395:Histocompatibility Antigens Class I / Q000097:blood / Q000235:genetics / Q000276:immunology*; D006801:Humans; D007114:Immunization; D007074:Immunoglobulin G / Q000096:biosynthesis / Q000097:blood / Q000145:classification; D007075:Immunoglobulin M / Q000096:biosynthesis / Q000097:blood / Q000145:classification; D007518:Isoantibodies / Q000096:biosynthesis* / Q000097:blood*; D008297:Male; D051379:Mice; D008875:Middle Aged; D055815:Young Adult; D000097625:HLA-E Antigens
chemical_list: D000911:Antibodies, Monoclonal; D001324:Autoantigens; D006680:HLA Antigens; D015395:Histocompatibility Antigens Class I; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D007518:Isoantibodies; D000097625:HLA-E Antigens