Comprehensive Analysis of HLA-DR- and HLA-DP4-Restricted CD4+ T Cell Response Specific for the Tumor-Shared Antigen Survivin in Healthy Donors and Cancer Patients

Abstract

Because of the wide distribution of the survivin Ag in a variety of tumors, we have investigated the survivin-specific CD4+ T cell response in healthy donors and cancer patients. Screening of the entire sequence of survivin for HLA class II binding led to the identification of seven HLA-DR promiscuous peptides, including four HLA-DP4 peptides. All of the peptides were able to prime in vitro CD4+ T cells of eight different healthy donors. The peptide-specific T cell lines were stimulated by dendritic cells loaded with the recombinant protein or with the lysates of tumor cells. The high frequency of responders (i.e., immunoprevalence) was provided by a wide reactivity of multiple peptides. Six peptides were T cell stimulating in at least half of the donors and were close to CD8+ T cell epitopes. HLA-DR molecules were more frequently involved in T cell stimulation than were HLA-DP4 molecules, and hence immunoprevalence relies mainly on HLA-DR promiscuity in the survivin Ag. In two cancer patients a spontaneous CD4+ T cell response specific for one of these peptides was also observed. Based on these observations, the tumor-shared survivin does not appear to be the target of immune tolerance in healthy donors and cancer patients and is a relevant candidate for cancer vaccine.

The Signal Peptide of the Tumor-shared Antigen Midkine Hosts CD4+ T Cell Epitopes

“…Most of the T cell lines are specific for the peptides 9 -23 and 14 -28, and very few are specific for the mature form of MDK. The number of T cell lines specific for the mature form of MDK we obtained was small compared with the results with other antigens such as survivin (40) or viral peptides (27,29). In our assays, the yield of T cell lines depends on the number of preexisting T cells in the blood of the donors at the initiation of the T cell culture.…”

Analysis of Spontaneous Tumor-Specific CD4 T-cell Immunity in Lung Cancer Using Promiscuous HLA-DR Telomerase-Derived Epitopes: Potential Synergistic Effect with Chemotherapy Response

“…Recombinants interleukin (IL) 7 (5 ng/mL; Peprotech) and IL-2 (20 UI/mL; Novartis) were added at days 1 and 3, respectively. At days 7 and 14, cells were stimulated with g-irradiated autologous PBMCs pulsed with 10 mmol/L of UCPs and 20 UI/mL IL-2 was added at days 8 and 15 as previously reported (27,28). At day 21, CD4 T cells were purified (Miltenyi) and the specificity of T cell lines was investigated by IFN-g ELISPOT.…”

“…Synthetic peptides (>80% purity) were purchased from Activotec. The binding capacity to HLA-DR molecules was assessed by competitive ELISA as previously reported (27).…”

“…Ficoll-isolated PBMCs from cancer patients or healthy volunteers were cultured with 10 mmol/L of pool of UCPs in a 24-well plate (4.10 6 cells per well) in RPMI 5% human serum and IL-7 (5 ng/mL) and IL-2 (20 UI/mL) were added at days 1 and 3, respectively (27). For the recall response against viruses, cells were similarly cultured with the mix of 32 peptides from cytomegalovirus, influenza virus, and Epstein-Barr virus (CTL).…”

Adeno-associated virus-mediated survivin mutant Thr34Ala cooperates with oxaliplatin to inhibit tumor growth and angiogenesis in colon cancer

“…Thus, targeting survivin pathway for cancer therapy has been widely investigated (18,25,(27)(28)(29). The studies have shown that the mutagenesis of Thr 34 ➝Ala completely suppressed survivin phosphorylation by p34 cdc2 -cyclin B1 in vitro and in vivo (17,30).…”