The development of novel mouse monoclonal antibodies against the CC531 ratcolon adenocarcinoma

In this paper we describe 4 new monoclonal antibodies to be applied in rat models for cancer. The monoclonal antibodies were obtained by immunizing Ba lb/c mice with CC531 rat colon adenocarcinoma cells. Hybridomas were produc ed and 4 were selected for their reactivity with CC531 in vitro (MG1, 2, 3 and 4). All 4 antibodies recognized other rat tumour cell lines and showed limited cross-reactivity with normal rat tissues. Intraperitoneally injecte d MG1, 2 and 4 homed to in vivo growing, artificially induced CC531 liver m etastases. In these in vivo experiments, limited cross-reactivity with norm al rat tissues, predominantly of the gastro-intestinal tract, was found. MG 4 was found to enhance lysis of CC531 tumour cells mediated by IL-2 activat ed, cultured natural killer cells. These antibodies are potentially useful for antibody-based laboratory techniques and for investigation of antibody- based immunotherapy of cancer in a rat model.