same tumor and recombinant proteins or foreign lymphocytes 
containing the HLA-B7 could be used to pre-immunize patients in 
future protocols designed to optimize the efficacy of this 
transfection procedure. 
A. 
B. 
Cell Target: CT26 CT26 H-2K 
25 - 
CT26 CT26 H-2K 
LYSIS 
(%) 
50 
i r 
i 
ANTIBODY: 
INHIBITION (%): 
- UT4 IHZ - UM IA 
- 0 99 - 35 93 
- UT4 IA - UT4 tA 
- 0 62 - 0 62 
Figure 3. Lysis of CT26 cells induced by injection of H-2K S is 
mediated by Lyt2 + cytolytic cells. 
Splenic lymphocytes were derived from non-immune (A) or H- 
2K S immunized (B.) BALB/c mice bearing CT26 tumors injected and 
cultured in vitro with irradiated 5 x 10 4 CT26-K S cells (2000R) . 
Tumors were injected with H-2K S plasmid DNA liposomes at days 10, 
14, and 17 (A) or 18, 25, and 30 (B) post-inoculation. 
Monoclonal antibodies to the indicated cell surface antigens were 
included in the cytolytic T cell assay at ef fector-to-target 
ratios of 25:1 (A) or 50:1 (B) , respectively. 
X. The ability of the RSV H-2K S vector to provide systemic 
immunity. 
The ability of the RSV-H-2K s expression vector to induce 
cytolytic T cell activity against CT26 following introduction in 
Recombinant DNA Research, Volume 15 
[439] 
