Association Of HLA ? Alleles With Pityriasis Rosea Of Han Population In Anhui Area

Background Pityriasis rosea(PR),first named in 1860 by Gibert,is a frequent acute inflammatory skin disease occurring worldwide.The patients present with oval erythematous maculopapules,macules and patches distributed over trunk and proximal extremities in Christmas tree-like pattern.This disorder mainly affects population with10-35 years old of age and usually lasts for 2-3 months.To date,the etiology and pathogenesis of this disease remains elusive.The viral infection hypothesis and cell-mediated immunity hypothesis are quite noted.The infection of human herpes viruses(HHV)6 or 7 is considered to be closely associated with PR in viral infection hypothesis.However,PR is suggested to be a cell-mediated immune disease in the immunity hypothesis.In 1985,Aiba and Tagami presented histologic findings of PR with exocytosis mononuclear cells in the epidermis,perivascular infiltration of numerous T helper cells and increased Langerhans cells in the superficial dermis.Moreover,the expression of HLA-DR antigen was observed on these lymphocytes and keratinocytes.Yoshiike et al found the expression of HLA-DR antigen was up-regulated on peripheral blood T lymphocytes,but gradually decreased and restored completely in the patients with PR.Sugiura et al showed the number of CD1 a and lymphocytes,the ratio of CD4+/CD8+T cells were positively related to the stage and severity of disease in the lesional skin of PR.Neoh et al observed the increase of Langerhans cells and the ratio of CD4+/CD8+ T cells in the skin lesions of this disease.However,the active B cells and NK cells were not present.Gangemi et al ? Drago et al respectively carried out the detection of cytokines and found the serum level of fractalkine,interleukin-(IL-)22,IL-17,IFN-?, VEGF,and IP-10 was increased in PR patients.However,we previously found the declined level of interferon-? in the sera of PR patients.There is few report about the relation of PR to HLA allels and haplotypes.In 2006,Miranda et al performed the genotyping of HLA alleles in 30 cases of Afro-Brazilian PR patients and 45 healthy controls and found that the frequency of HLA-DQB1*04allele in patients was significantly higher than that in normal controls(33.3% vs 11.1%,RR=4.00,95% CI=1.20�13.28,P = 0.018).It suggested HLA-DQB1*04 allele was associated with the risk of PR.Up to now,there is no study on this condition in Chinese patients with PR.Objective We investigate the relationship between HLA II Alleles and Pityriasis rosea in Chinese patients to demonstrate the immune pathogenesis of PR.Method We collected the data and blood samples from 55 cases of PR patients and 90 healthy controls in this case-controls study.HLA-DRB1 genotying was performed by sequence-based typing(SBT)method and-DQA1 and-DQB1 genotying was performed by polymerase chain reaction sequence-specific primers(PCR-SSP)method respectively.Chi-square test was used to analyze whether there are differences in the frequencies of these alleles between PR patients and normal controls or not.Results The frequency of HLA-DQB1*03:03 was significantly higher in the PR group compared with the controls(47.27% vs 21.11%,P = 0.001;RR = 2.239;95%CI:1.376-3.645).Conclusions In conclusion,the association of HLA-DQB1*03:03 with PR suggests participation of immunity in the pathogenesis of PR.In addition,HLA-DQB1*03:03 allele may be a susceptible factor in PR patients.