Modified vaccinia virus Ankara for delivery of human tyrosinase as melanoma-associated antigen: induction of tyrosinase- and melanoma-specific human leukocyte antigen A*0201-restricted cytotoxic T cells in vitro and in vivo.
Vaccination with tumor-associated antigens is a promising approach for cancer immunotherapy. Because the majority of these antigens are normal self antigens, they may require suitable delivery systems to promote their immunogenicity. A recombinant vector based on the modified vaccinia virus Ankara (MVA) was used for expression of human tyrosinase, a melanoma-specific differentiation antigen, and evaluated for its efficacy as an antitumor vaccine. Stable recombinant viruses (MVA-hTyr) were constructed that have deleted the selection marker lacZ and efficiently expressed human tyrosinase in primary human cells and cell lines. Tyrosinase-specific human CTLs were activated in vitro by MVA-hTyr-infected, HLA-A*0201-positive human dendritic cells. Importantly, an efficient tyrosinase- and melanoma-specific CTL response was induced in vitro using MVA-hTyr-infected autologous dendritic cells as activators for peripheral blood mononuclear cells derived from HLA-A*0201-positive melanoma patients despite prior vaccination against smallpox. Immunization of HLA-A*0201/Kb transgenic mice with MVA-hTyr induced A*0201-restricted CTLs specific for the human tyrosinase-derived peptide epitope 369-377. These in vivo primed CTLs were of sufficiently high avidity to recognize and lyse human melanoma cells, which present the endogenously processed tyrosinase peptide in the context of A*0201. Tyrosinase-specific CTL responses were significantly augmented by repeated vaccination with MVA-hTyr. These findings demonstrate that HLA-restricted CTLs specific for human tumor-associated antigens can be efficiently generated by immunization with recombinant MVA vaccines. The results are an essential basis for MVA-based vaccination trials in cancer patients.
Drexler
I
I
GSF-Institute for Molecular Virology, Munich, Germany. drexler@gsf.de
Antunes
E
E
Schmitz
M
M
Wölfel
T
T
Huber
C
C
Erfle
V
V
Rieber
P
P
Theobald
M
M
Sutter
G
G
D000818:Animals; D002460:Cell Line; D003713:Dendritic Cells / Q000276:immunology / Q000502:physiology; D004790:Enzyme Induction; D005819:Genetic Markers; D005822:Genetic Vectors; D015234:HLA-A Antigens / Q000276:immunology*; D006801:Humans; D008213:Lymphocyte Activation; D008545:Melanoma / Q000276:immunology*; D051379:Mice; D008822:Mice, Transgenic; D014442:Monophenol Monooxygenase / Q000096:biosynthesis* / Q000235:genetics*; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D017384:Sequence Deletion; D012900:Smallpox Vaccine; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D014162:Transfection; D014616:Vaccinia virus
D005819:Genetic Markers; D015234:HLA-A Antigens; D011993:Recombinant Fusion Proteins; D012900:Smallpox Vaccine; D014442:Monophenol Monooxygenase