Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2003-7-10
pubmed:abstractText
The causal association between papillomavirus (HPV) infection and cervical cancer has been demonstrated; the development of a prophylactic vaccine to protect against HPV infection may therefore reduce the incidence of this cancer worldwide. Noninfectious HPV-like particles (VLPs), composed of the L1 major capsid protein, are current candidate vaccines for prevention of HPV infection and cervical neoplasia. Although neutralizing antibodies have a pivotal role in the prevention of initial infection, cellular immune responses to HPV antigens may have an important role in viral clearance. A phase II trial was conducted to further evaluate the immunogenicity of a recombinant HPV-16 L1 VLP vaccine administered intramuscularly, without adjuvant, at 0, 1, and 6 months. Cell-mediated immune responses (lymphoproliferation and cytokine production) to HPV-16 L1 VLPs were evaluated in peripheral blood mononuclear cells (PBMCs) from 43 individuals receiving the L1 VLP vaccine and from 10 individuals receiving placebo. Vaccination resulted, at months 2 and 7 (i.e., 1 month after the second immunization and 1 month after third immunization, respectively), in increases in T cell-proliferative response to HPV-16 L1 VLPs (P<.001). In addition, significant increases in cytokine (interferon-gamma, interleukin [IL]-5 and IL-10) responses to L1 VLPs were observed after vaccination (P<.001). The strongest cytokine responses at month 7 were observed in individuals with high antibody titers at month 2, suggesting that neutralizing antibodies generated by initial vaccination may augment T cell responses to subsequent booster vaccinations. No significant increases in lymphoproliferative or cytokine responses to L1 VLPs were observed in individuals receiving placebo. In summary, the HPV-16 L1 vaccine induces not only robust B cell responses but also L1-specific T cell responses detectable by proliferation of both CD4+ and CD8+ T cells and in vitro production of both Th1- and Th2-type cytokines. Future efficacy studies are needed to evaluate whether and/or how VLP vaccines confer protection against genital HPV infection and associated disease.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0022-1899
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
188
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
327-38
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
Cellular immune responses to human papillomavirus (HPV)-16 L1 in healthy volunteers immunized with recombinant HPV-16 L1 virus-like particles.
pubmed:affiliation
SAIC-Frederick, Inc./National Cancer Institute, Building 469, Room 120, Frederick, MD 21702, USA. lpinto@ncifcrf.gov
pubmed:publicationType
Journal Article, Clinical Trial, Research Support, U.S. Gov't, P.H.S., Randomized Controlled Trial