2021 Volume 33 Issue 02 Pages 69-75
Laryngeal papilloma (LP) is a tumor caused by infection of the larynx with human papillomavirus type 6 or 11 (HPV-6 or HPV-11) and is a multiple, recurrent, and refractory disease. HPV-6 and HPV-11 have nine genes, but the detailed functions of these genes in the formation of recurrent and refractory LP have not been elucidated. We examined the viral DNA load and mRNA expression as well as the in situ localization in HPV-6-infected LP. Our novel phage display method produced a monoclonal antibody against the viral E4 protein as E4 mRNA was found to be the most highly expressed of the nine viral mRNAs. The average viral load was 4.80 × 105 ± 1.86 × 105 copies/ng DNA. E4, E5a, and E5b mRNAs accounted for 96% of the expression of the 9 mRNAs. The changes in the viral DNA load and expression of the nine mRNAs showed a similar curve during recurrence. The E4, E5a, and E5b mRNAs were co-expressed in the middle to the upper part of the epithelium. These results suggest that individual viral genes are coordinately expressed for viral replication, virus release, and immunosurveillance avoidance. Antibody against HPV-6 E4 shows high sensitivity and specificity in western blotting and immunohistochemistry and can be used for further functional studies and clinical applications.
