RAG1 and neoplasm: To investigate the effects of CD40-mediated E-cadherin + DCs isolated from the spleens of anti-CD40 Rag1 KO mice on the Th1 and Th2 responses in the tumour microenvironment, naive CD4+ T cells were incubated for 96 h with E-cadherin + DCs or E-cadherin- DCs, both of which had been pre-incubated with 5 μg/ml CEA421-435 peptide for 24 h.