ERBB2 and neoplasm: In addition, cytotoxic T lymphocyte (CTL) responses against HER-2/neu+ tumours have been induced in vitro using major histocompatibility complex (MHC) class I-binding synthetic peptides derived from the HER-2/neu sequence (Fisk et al, 1995; Linehan et al, 1995; Brossart et al, 1998; Rongcun et al, 1999; Baxevanis et al, 2002).