Document Type: Research Articles
Postgraduate Program in Health Sciences, Federal University of Rio Grande do Norte, Natal, Brazil.
Department of Gynecology, and Obstetrics, Federal University of Rio Grande do Norte, Natal, Brazil.
Department of Clinical Analysis and Toxicology, Federal University of Rio Grande do Norte, Natal, Brazil.
Department of Gynecology and Obstetrics, University Potiguar, UnP Natal, Brazil.
Department of Gynecology, and Obstetrics, State University of Campinas, Campinas, Brazil.
Department of Obstetrics and Gynecology Weill Cornell Medical College, New York, NY, USA.
Objective: This study was designed to describe the course of IgG/IgA responses in cervical secretions and in serum
one year after the first dose of intramuscular administration of the HPV16/18 AS04-adjuvant vaccine. Methods: Blood
and cervical mucus samples were collected for immunologic assays, 7 months after the first doses and 1 year following
the last boost vaccination (month 7) by enzyme linked immunosorbent assay (ELISA). The detection of IgG and IgA
anti-HPV/VLP was developed for this purpose. Result: A total of 100% of serum samples were IgG antibody positive
at a titer of 1:100 at both time periods and decreased according to the serum dilution. For serum IgA antibody, 95%
were positive one month after vaccination and 79% were positive 1 year later. Similar results were observed with
the cervical samples positive for both IgG and IgA antibodies at one month and decreasing after 1 year to 33% and
29%. The median absorbance in serum and the cervix for IgG and IgA anti-HPV-VLP antibodies was significantly
higher at one month after vaccination when compared to 1 year post-vaccination (P<0.0001). Conclusion: Immune
responses were significant one year after immunization, however it decreased in cervical and serum samples when
compared to levels observed one month after the last dose. This suggests that a vaccine booster may be necessary to
increase antibody titers.