Murine IgE antibodies recognising a mammary tumour virus antigen and a colorectal cancer antigen were each able to restrict the growth of subcutaneous tumours at lower doses than required for the equivalent IgG [24,25]; and, similarly, a human anti-HER2 IgE both restricted intraperitoneal tumour growth and prolonged the survival of mice transgenic for human FcεRIα. Here, ERBB2 is linked to neoplasm.