A canarypox vector-expressing cytomegalovirus (CMV) phosphoprotein 65 induces long-lasting cytotoxic T cell responses in human CMV-seronegative subjects

J Infect Dis. 2001 Apr 15;183(8):1171-9. doi: 10.1086/319680. Epub 2001 Mar 13.


The major matrix phosphoprotein 65 (pp65) of cytomegalovirus (CMV) is an important target of HLA-restricted cytotoxic T cells (CTL) after natural infection. A canarypox-CMV pp65 recombinant was studied for its ability to induce CMV pp65-specific CTL, helper T lymphocytes, and antibodies in a phase I clinical trial. Twenty-one CMV-seronegative adult volunteers were randomized to receive immunizations at months 0, 1, 3, and 6 with either canarypox-CMV pp65 or placebo. In canarypox-CMV pp65-immunized subjects, pp65-specific CTL were elicited after only 2 vaccinations and were present at months 12 and 26 in all subjects tested. Cell-depletion studies indicated that the CTL were phenotype CD8(+). Peripheral blood mononuclear cells proliferated in response to stimulation with purified pp65, and antibodies specific for pp65 also were detected. Canarypox-CMV pp65 is the first recombinant vaccine to elicit CMV-specific CTL responses, which suggests the potential usefulness of this approach in preventing disease caused by CMV.

Publication types

  • Clinical Trial
  • Clinical Trial, Phase I
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Antibodies, Viral / blood*
  • Antibody Formation
  • Antibody Specificity
  • Avipoxvirus / genetics
  • Avipoxvirus / immunology
  • CD8-Positive T-Lymphocytes / immunology
  • Cell Line
  • Cytomegalovirus / immunology*
  • Cytomegalovirus Infections / immunology*
  • Cytotoxicity, Immunologic
  • Genetic Vectors
  • Humans
  • Immunity, Cellular
  • Phosphoproteins / genetics
  • Phosphoproteins / immunology*
  • T-Lymphocytes, Cytotoxic / immunology*
  • T-Lymphocytes, Helper-Inducer / immunology*
  • Vaccines, Synthetic / adverse effects*
  • Viral Matrix Proteins / genetics
  • Viral Matrix Proteins / immunology*
  • Viral Vaccines / adverse effects*


  • Antibodies, Viral
  • Phosphoproteins
  • Vaccines, Synthetic
  • Viral Matrix Proteins
  • Viral Vaccines
  • cytomegalovirus matrix protein 65kDa