In this model, the anti-CSPG4 IgE antibody significantly restricted the growth of A375 tumors and patient-derived xenograft tumors compared to the nonspecific IgE control antibody and significantly greater macrophage infiltration into tumor tissues was observed in animals treated with anti-CSPG4 IgE.34 An alternative would be to use an immunocompetent model and surrogate antibodies engineered to be of the same host species. This evidence concerns the gene IGHE and neoplasm.