Cervico-vaginal humoral response (IgA secretora) in women wich received the quadrivalent vaccine against HPV

Abstract

HPV vaccination has been found to be very effective against infection, however little is known concerning its therapeutic properties. Secretory IgA (sIgA) neutralizes viruses from inside the infected cells by means of transcytosis, which could explain possible therapeutic qualities. Objective: To quantify and compare the specific and total secretory IgA levels before and after vaccination. Subjects and Methods: This clinical study on immunogenicity will evaluate vaginal secretory IgA in 60 healthy women between the ages of 18 and 26, all without induced HPV lesions or history, as well as negative Pap smears. Samples will be collected from the uterine cervix for detection and genotyping of HPV 6, 11, 16 and 18 as well as quantification of total and specific sIgA. Collection will take place on day zero, as well as six months and twelve months after vaccination. Sample size was based on previous studies, wherein sIgA levels before and after vaccination were estimated. Considering a test with 80% power and 5% significance level, the required sample size was calculated at n = 46. The statistics suggest sample size be increased by 10% to 20% due to losses accrued during follow-up. Our hypothesis is that vaccinated women will present higher levels of sIgA specific to HPV 6,11,16 and 18. (AU)