Contribution of HLA‐B*51:01 and ‐A*26:01 to Behçet's disease and their clinical association in Thai patients

Abstract

Aims To investigate susceptible human leukocyte antigen (HLA) alleles and their associations with clinical features in Thai patients with Behçet's disease (BD). Method Eighteen HLA‐A and 36 HLA‐B alleles were determined in 42 Thai BD patients and 99 healthy controls (HCs) by reverse line blot assay, and reconfirmed by MICRO SSP assay. Results The BD patients had significantly higher allele frequency (AF) of HLA‐B*51 than the HCs (13.10% vs 5.05%, P = .025). The AF of HLA‐A*26, ‐A*26:01 and ‐B*51:01 also was higher and almost reached statistical significance (5.59% vs 1.52%, P = .054, 5.95% vs 1.52%, P = .054 and 10.71% vs 4.04%, P = .051, respectively). However, the BD patients had significantly higher AF of either HLA‐A*26:01 or ‐B*51:01 (16.67% vs 5.56%, P = .005), or ‐A*26:01 or ‐B*51X (19.05% vs 6.56%, P = .003). The AF of HLA‐B*51:01 and ‐B*51X increased significantly in ‐A*26:01 non‐carrier BD patients (12.16% vs 4.17%, P = .024 and 14.86% vs 5.21%, P = .019, respectively); and that of HLA‐A*26:01 was significantly higher in ‐B*51X non‐carrier BD patients (7.58% vs 1.67%, P = .034). HLA‐B*51:01 associated significantly with the presence of posterior uveitis and visual impairment (18.18% vs 2.50%, P = .031 for both conditions). HLA‐B*51:01 was not observed in BD patients with gastrointestinal involvement or arthritis. Furthermore, the AF of HLA‐B*51:01 was significantly higher in HLA‐A*26:01 non‐carrier BD patients without arthritis (17.30% vs 0%, P = .050). Conclusion HLA‐B*51:01 was a susceptible allele for Thai BD patients, and associated with posterior uveitis and visual impairment. HLA‐A*26:01 was another susceptible allele in HLA‐B*51X non‐carrier patients. The protective effect of HLA‐B*51:01 on arthritis needs further investigation.

HLA Alleles in a Behçet Disease Multiethnic Population With and Without Ophthalmic Manifestations

“…The HLA-A*26 allele has been described in other populations 13,39,40 as a risk factor for BD development; however, it did not occur at a significant frequency after Bonferroni correction in our study population. HLA-A*26 carriers have been reported to have a higher risk of iridocyclitis and retinochoroiditis, which is more prominent in men.…”

“…12 In addition, associations between HLA-A*26:01 and the development of BD and related uveitis have been reported. [12][13][14] Ophthalmic manifestations (OMs) are present as an initial symptom in BD in 10% to 20% of patients and are the second most frequent manifestation after oral ulcers, in conjunction with neurological manifestations. 15 Ophthalmic manifestation in BD is associated with a high risk of irreversible, partial and complete, vision loss.…”

“…Recently, associations between BD and certain alleles adjacent to the HLA-B locus in the tumor necrosis factor (TNF)–stimulating region, such as TNF*B1 and TNF*B2, have been described 12 . In addition, associations between HLA-A*26:01 and the development of BD and related uveitis have been reported 12–14 …”

Uncommon P1 Anchor-featured Viral T Cell Epitope Preference within HLA-A*2601 and HLA-A*0101 Individuals

“…HLA-A*0101 and HLA-A*2601 have been associated with a variety of diseases. For example, HLA-A*2601 is considered a susceptible allele in HLA-B*51X noncarrier patients with Behçet’s disease ( 12 ) and may be considered as a protective allele against pemphigus vulgaris in Iranian patients ( 13 ). It is also significantly increased in idiopathic hypoparathyroidism compared with controls ( 14 ).…”