title: Structural and functional distinctiveness of HLA-A2 allelic variants.
abstract: Human leukocyte antigen (HLA) class I molecules are involved in the presentation of antigenic peptides to CD8(+) cytotoxic T lymphocytes (CTLs), which is important for the development of cellular immunity during viral infections and in cancers. HLA-A2 is one of the most frequent HLA class I specificities and thus is extensively studied structurally and functionally. Since its discovery, more than 300 allelic variants of this HLA specificity have been recorded. Among the HLA-A2 allelic variants, HLA-A*02:01 is the most prevalent, hence commonly used as a model to study HLA-A2-restricted CTL responses. However, HLA-A2 alleles are unevenly distributed globally such that HLA-A2 allelic variants besides A*02:01 are expressed at considerably high frequencies in Asian and African populations. Furthermore, increasing evidence of variations in the peptide-binding repertoire and CTL responses among HLA-A2 allelic variants suggests the need to understand these differences among various frequently expressed HLA-A2 molecules. In this review, the structural and functional distinctiveness of HLA-A2 allelic variants will be discussed.
authors.affiliation: Singapore Immunology Network, Agency for Science, Technology and Research (A*STAR), 8A Biomedical Grove, #03-06 Immunos, Singapore.
authors.forename: Kenneth Yuanxiang
authors.initials: KY
authors.lastname: Chen
authors.forename: Jingxian
authors.initials: J
authors.lastname: Liu
authors.forename: Ee Chee
authors.initials: EC
authors.lastname: Ren
mesh_terms: D017951:Antigen Presentation; D044466:Asian People; D044383:Black People; D003460:Crystallization; D005787:Gene Frequency; D014644:Genetic Variation; D015789:HLA-A2 Antigen / Q000737:chemistry* / Q000235:genetics* / Q000276:immunology; D006801:Humans; D008213:Lymphocyte Activation; D008968:Molecular Conformation; D011485:Protein Binding / Q000276:immunology; D013329:Structure-Activity Relationship; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*
chemical_list: D015789:HLA-A2 Antigen