In situ application of IL-2 avoids toxicity associated with systemic administration and provides an efficient immune stimulatory activity. Taking advantage from the targeting ability of a tumor-specific monoclonal antibody, a fusion protein was constructed that allowed the specific targeting of IL-2 at tumor site. The complete cDNA encoding human IL-2 was linked to the scFv (if the MOV 19, a monoclonal Ab that recognizes the gp38 folate binding protein (FBP), which is overexpressed in human ovarian carcinomas. The 3' end of MOV19 cDNA was modified to include a splicing donor site and the entire sequence was cloned into the pH PCR vlll-Ck expression vector that encodes the constant portion of murine Ig k (Ck) light chain under the control of the murine Ig k promoter and Ig heavy chains enhancer. Upon splicing of the transcribed mRNA the Ck sequence was joined 3' to the fusion protein cDNA. J558L murine myeloma cells were transfected with the construct and different clones were screened for the production of IL-2/MOV19 fusion protein through ELISA for human IL-2 and for murine Ck. The IL-2/MOV19 tusion protein was able to bind the gp38/FBP tumor antigen on human ovarian carcinoma cells IGROV-1, and to stimulate the proliferation of the II, 2 dependent CTL1.2 cell line. A murine tumor model was constructed by transducing the human gp38/FBP into two poorly immunogenic BALB/c tumors by mean of retroviral vector. Both gp38/FBP positive tumors were targeted in vitro by the 1L-2/MOV39 fusion protein thus accounting for its use in Ko m immune therapy experiments. Supported by AIRC.
|Publication status||Published - 1997|
ASJC Scopus subject areas
- Agricultural and Biological Sciences (miscellaneous)
- Biochemistry, Genetics and Molecular Biology(all)
- Cell Biology