HER-2/neu-specific T cell responses in patients with HER-2/neu negative or positive breast cancers. Peripheral blood T cells were isolated from patients with HER-2/neu positive (patients #7, 13, 14) or HER-2/neu negative (all other patients) breast cancers (stage I-III) (A) and two samples from DCIS patient (B). T cells were then co-cultured with or without DCs in a 2:1 ratios in the presence or absence of recombinant human HER-2/neu (intracellular domain + extracellular domain: ECD+ICD, 100 μg/ml) for 24 hrs. Supernatants were collected and subjected to IFN-γ ELISA. C) Representative IHC staining (200× magnification) of tumor lesions of patients with HER-2/neu negative (-) and HER-2/neu positive (+) tumors who had HER-2/neu-specific T cell responses or no T cell responses.