Recurrent Respiratory Papillomatosis, HPV, and Impact on Host Response
Andrea Vambutas and Bettie M. Steinberg
from: Papillomavirus Research: From Natural History To Vaccines and Beyond (Edited by: M. Saveria Campo). Caister Academic Press, U.K. (2006)
Recurrent Respiratory Papillomatosis (RRP) is a devastating disease characterized by multiple recurrent, benign growths that cause significant morbidity by airway obstruction. Adjunct therapy to traditional surgical removal has been sought due to the aggressive nature of the disease. The lesions are caused by human papillomavirus (HPV) type 6 and 11. Although many of the same papillomavirus proteins are expressed in high risk HPV types, the function of these proteins are different in the low risk HPVs 6 and 11. In laryngeal papillomas cells, there is a defect in terminal differentiation and significant alterations in signal transduction. Latent viral infection is commonplace, and the triggers for activation of latency are unknown. Host immune responses demonstrate local immunocompromise, where many components for an appropriate immune response are reduced in papillomas. Ubiquitously expressed viral proteins are obvious targets for vaccine development. Unfortunately, the two most common targets, E6 and E7, either fail to induce any response or initiate inappropriate Th2-like responses. This has led investigators to increase immunogenicity of these proteins. To date, a completely successful therapeutic vaccine has not been identified. An ideal therapeutic vaccine in RRP would require the control of active and latent disease, with a minimal inflammatory response read more ...