Association analysis between human papillomavirus genotypes and viral load and clinical features of verruca vulgaris / 中华皮肤科杂志

ABSTRACT

Objective To study the association between human papillomavirus (HPV) genotypes and viral load and clinical features of verruca vulgaris.Methods Tissue samples were collected from 48 outpatients with verruca vulgaris,and DNA was extracted from these tissue samples.To determine the genotype of HPV,PCR was performed to amplify the L1 fragment of HPV with universal primers followed by bidirectional sequencing and BLAST.The genotyping results were validated by PCR with type-specific primers.Real-time fluorescence-based quantitative PCR was conducted to measure the viral load of HPV,and hematoxylin and eosin (HE) staining to observe histological changes in these tissue specimens.Results The L1 fragment of HPV was amplified from 35 out of the 48 tissue specimens.Of the 35 L1-positive specimens,32 harbored HPV 7,1 harbored HPV 57,and 2 harbored both HPV 2 and HPV 7.Multiple lesions were observed on extremities in the patient infected with HPV 57,but on the head,face and trunk in the patients coinfected with HPV 2 and HPV 7.There were no significant differences in HPV viral load or vacuolated cell number between patients with single lesions and those with multiple lesions,or between patients with a clinical course of ＜ 6 months and those with a clinical course of 6-12 months.However,HPV viral load tended to decrease one year after the onset,and there was pronounced hyperkeratosis and less vacuolated cells in lesions of long duration (more than 2 years) compared with those of short duration (less than 2 years).Conclusions HPV 7 appears to be the most common HPV genotype associated with verruca vulgaris,and HPV 7 infection usually occurs on the head and face.For verruca vulgaris of less than 1 year,neither HPV viral load nor vacuolated cell number is associated with the count or clinical course of warts.