I 
transfection of H-2t> melanoma cells with the H-2D<^ gene did not lead to rejection (59), 
however increased differenticil expression of H-2D products relative to H-2K may have 
affected the metcistatic potential and immunogenicity of tumor cells (60). The effects of 
allogeneic H-2K gene expression in tumor cells was examined in another study (61). 
Several subclones which were selected in vitro and expressed cin allogeneic gene were 
rejected in mice syngeneic for the parental tumor line, however, other subclones did not 
differ from the parental, untransduced line in generating tumors. This finding suggests 
that clone-to-clone variation in in vivo growth and tumorigenic capacity may result in 
other modifications of cells caused by transfection or the subcloning procedure, which 
affects their tumorgenidty. These types of clonal differences would likely be 
minirnized by transducing a population of cells directly in vivo. 
Because the H-2K class I MHC antigen is strongly expressed on most tissues and can 
mediate an allogeneic rejection response, we chose it in our animal model studies 
designed to enhance the immunogenicity of tumors in vivo. These studies extended 
previous efforts to modify tumor cells by developing a system for the direct 
introduction of genes into tumors by in vivo infection using retroviral vectors or by 
DNA lipid complex mediated transfection- This technology can also be used to deliver 
specific recombinant cytokines into the tumor microcirculation and to understand the 
immunologic basis for tumor rejection in vivo. 
2.0 OBJECTIVES 
2.1 To determine safety and toxicity of direct intralesional injection of mcreasing 
amounts of a DNA/lipid mixture: VCL 1005 (HLA-B7/DMRIE/E)OPE) into 
patients with metastatic malignant melanoma. Escalating treatment regimens will 
be used and tumor growth evaluated. 
2.2 To measure the cytotoxic T cell activity directed towards antigens on tumor cells 
other than HLA-B7. 
2.3 To measure humoral and cellular immune responses to HLA-B7. 
2.4 To confirm expression in vivo of the HLA-B7 gene in the tumor cells. 
2.5 To characterize the clinical response to escalating doses of the study drug by 
assessing the size of the injected tumor and of all other tumor masses that may be 
present. 
3.0 STUDY DESIGN 
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