For many years it has been hoped that vaccination against cancer may 
specifically sensitize the host immune system and induce an antitumor response. 
At MSKCC, a variety of tumor vaccine studies aimed at inducing or augmenting 
a humoral or cellular antitumor response have been completed. Most of these 
studies have been done in patients with melanoma. Since there is more 
experience on the use of vaccines for melanoma, our trial will be based in part 
on the observations that have been made for melanoma. 
In the initial trials with autologous and allogenic melanoma cell vaccines, 
Livingston et al (28) tested for augmentation of cell mediated cytotoxicity against 
cultured melanoma cells. No augmentation was seen and the specificity analysis 
of preexisting cell mediated cytotoxicity was found to be difficult. Consequently, 
emphasis was placed on serologic analysis. In the analysis of reactions of 
patient’s sera with autologous cultured melanoma cells, three classes of cell 
surface antigens have been defined (28). Class I are unique antigens detected 
only on autologous cells. Class II are restricted differentiation antigens shared by 
many melanoma cell lines. Class III are nonspecific antigens seen on normal 
cells and other non-melanoma tumor cells. 
Cytotoxic T cells that kill allogenic tumor cells have been found to be class I 
restricted. These cytotoxic T lymphocytes could kill HLA matched but not non- 
HLA matched allogenic melanoma cells (40,41). Further evidence for shared 
tumor antigens is growing. Houghton (unpublished data) has noted that CD 4 + 
cells can kill both autologous and allogeneic tumor cells and these recognize 
shared antigens restricted by HLA-DR 15. Crowley (46,47) demonstrated that 
autologous tumor- specific cytotoxic T-lymphocytes (CTL’s), when generated by 
repeated stimulation with autologous melanoma cells and expanded in the 
presence of interleukin-2, were major histocompatibility restricted (46,47). 
Additional experiments suggested that these CTL’s recognized a tumor-associated 
antigen in the presence of HLA-A2. Allogeneic HLA-A2 matched melanoma 
cells were substituted for autologous tumor cells in the generation of CTL’s. 
These lymphocytes lysed the autologous tumor cells to the same degree that 
CTL’s generated by stimulation with autologous tumor cells. Thus, tumor 
specific CTL’s could be generated using HLA-2 matched allogeneic melanoma 
cells. Since growing autologous tumor cells in culture is a time intensive 
procedure, allogenic HLA-A2 cells could be used to generate autologous 
cytotoxic T cells. 
2.3 Biologic effects in vitro of Interleukin-2 
Interleukin-2 is a lymphokine that is produced by T helper cells and stimulates T 
cells and natural killer (NK) cells. In vitro IL-2 has been shown to cause 
proliferation of antigen specific T cells. Helper, cytotoxic, and suppressor T cells 
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