Only a small proportion of women infected with human papillomavirus type 18 (HPV18) may progress to persistent infection and cervical neoplasia. This community-based cohort study aimed to assess associations with human leukocyte antigen (HLA) class II genotypes for natural infection of HPV18 and subsequent risk of cervical neoplasia.
Among 10,190 cytologically normal participants, 125 with HPV18 infection were identified by HPV blot kit. HPV18 viral load at study entry was examined by real-time polymerase chain reaction; persistent infection was defined as HPV18 infection at 2 consecutive examinations.
There was a significant association between HLA-DRB1*0403 allele and high HPV18 viral load (>1000 copies in 50 ng of total DNA) at study entry (odds ratio [OR], 7.2; 95% confidence interval [CI], 2.0-25.2). After adjustment for age and viral load at study entry, haplotype HLA-DRB1*0405-DQA1*0301-DQB1*0302 was significantly associated with persistent HPV18 infection (OR, 13.3; 95% CI, 1.7-105.9). HLA-DRB1*0403 allele was also associated with a significantly increased risk of high-grade squamous intraepithelial lesion or cancer, showing a multivariate-adjusted hazard ratio (95% CI) of 18.1 (2.6-128.5).
HLA-DRB1*0403 allele and HLA-DRB1*0405-DQA1*0301-DQB1*0302 haplotype may play important roles in determination of high viral load and persistent infection of HPV18 and subsequent cervical neoplasia risk.