HLA-A2-Restricted Epitopes Identified from MTA1 Could Elicit Antigen-Specific Cytotoxic T Lymphocyte Response

Figure 2

IFN-γ release and lyse target cell ability of peptide-induced CTLs. PBMCs from six HLA-A02⁺ healthy donors were collected and induced by the indicated peptides (10 μg/ml) three times in RPMI 1640 medium supplemented with 3 μg/ml β2-M (once at each stimulation), interleukin-2 (50 U/ml, on day 3 and 1 day after each stimulation), and 10% FCS for 21 days. CTLs induced by COX-2_321–329 were used as positive controls. On day 21, the CTLs were collected, and the IFN-γ secretion and cytotoxic activity of the CTLs were measured. (a) CTL secretion of IFN-γ was detected by the ELISPOT assay (). T2 cells loaded with/without peptide (50 μg/ml) for 4 h were used as the stimulating cells. LDH cytotoxicity assays were performed () using the following target cell lines: (b) SW620 (HLA-A2⁺, MTA1⁺), (c) MDA-MB-231 (HLA-A2⁺, MTA1⁺), (d) SW620 incubated with an anti-human HLA-A2 antibody (HLA-A2⁻, MTA1⁺), (e) HT-29 (HLA-A2⁻, MTA1⁺), (f) MCF-7 (HLA-A2⁺, MTA1⁺), (g) HUVEC (HLA-A2⁺, MTA1^low), and (h) Het-1A (HLA-A2⁺, MTA1^low). CTLs induced by PBS were used as the negative control. Data represent means ± standard deviation (SD), , , and vs. the PBS group.

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