ERBB2 and neoplasm: To test whether antitumoural responses resulting from vaccination with liposomal constructs were dependent on the expression of ErbB2 by the tumour cells, two groups of mice were vaccinated twice on days 0 and 14 by s.c. injection of Tc-ErbB2/Th-HA liposomes, corresponding to 15 μg of coupled Tc-ErbB2 peptide per injection.