ERBB2 and neoplasm: As recipients of the tumour cells, we used either non-syngeneic WT BALB/c mice in which, due to the fact that the rat-neu molecule is a non-self-antigen, the tumour might be highly immunogenic, or syngeneic transgenic BALB/c-NeuT mice for which the rat-neu is a self-antigen and therefore the tumour might be poorly immunogenic25.