Identification of human leukemia antigen A*0201-restricted epitopes derived from epidermal growth factor pathway substrate number 8

Abstract

T-cell-mediated immunotherapy of hematological malignancies requires selection of targeted tumor-associated antigens and T-cell epitopes contained in these tumor proteins. Epidermal growth factor receptor pathway substrate 8 (EPS8), whose function is pivotal for tumor proliferation, progression and metastasis, has been found to be overexpressed in most human tumor types, while its expression in normal tissue is low. The aim of the present study was to identify human leukemia antigen (HLA)-A*0201-restricted epitopes of EPS8 by using a reverse immunology approach. To achieve this, computer algorithms were used to predict HLA-A*0201 molecular binding, proteasome cleavage patterns as well as translocation of transporters associated with antigen processing. Candidate peptides were experimentally validated by T2 binding affinity assay and brefeldin-A decay assay. The functional avidity of peptide-specific cytotoxic T lymphocytes (CTLs) induced from peripheral blood mononuclear cells of healthy volunteers were evaluated by using an enzyme-linked immunosorbent spot assay and a cytotoxicity assay. Four peptides, designated as P455, P92, P276 and P360, had high affinity and stability of binding towards the HLA-A*0201 molecule, and specific CTLs induced by them significantly responded to the corresponding peptides and secreted IFN-γ. At the same time, the CTLs were able to specifically lyse EPS8-expressing cell lines in an HLA-A*0201-restricted manner. The present study demon-strated that P455, P92, P276 and P360 were CTL epitopes of EPS8, and were able to be used for epitope-defined adoptive T-cell transfer and multi-epitope-based vaccine design.

A dual-function epidermal growth factor receptor pathway substrate 8 (Eps8)-derived peptide exhibits a potent cytotoxic T lymphocyte-activating effect and a specific inhibitory activity

“…Few effective CTL epitopes derived from Eps8 have been identified to date, and those that have are restricted to HLA-A*0201 and HLA-A*1101 17 , 18 , 27 . Although HLA-A*2402 is one of the most common epitopes in different human races, HLA-A*2402-restricted Eps8 epitopes have not yet been reported.…”

“…In the present study, we focused on Eps8 as a promising tumor antigen that drives induction of CTL responses against cancer cells. The use of peptide-based vaccines is a powerful and promising method to induce antigen-specific CTLs in cancer patients, and several clinical trials have been carried out 16 – 18 . Human leukocyte antigen (HLA)-A2 is the dominant type in Caucasians; therefore, HLA-A2-restricted peptide-based cancer immunotherapy has mainly been performed 19 , 20 .…”

In Silico Analysis of Epitope-Based Vaccine Candidates against Hepatitis B Virus Polymerase Protein

“…The epitopes of EPS8 predicted by computer algorithms have been validated by T2 binding affinity assay and brefeldin-A decay assay. The CTLs induced by these epitopes were able to secrete IFN-γ and lyse EPS8-expressing cell lines [ 72 ]. Additionally, the epitopes of heparanase (Hpa) selected by bioinformatics technology could upregulate expression of the HLA-A2 molecule on T2 cells.…”

Human leukemia antigen-A*0201-restricted epitopes of human endogenous retrovirus W family envelope (HERV-W env) induce strong cytotoxic T lymphocyte responses

“…Furthermore, the polypeptides recognized by CTLs are bound to MHC on antigen presenting cell surfaces. So, we combined SYFPEITHI and BIMAS analysis to predict peptides that could significantly save time by narrowing the validation scope (Tang et al, 2015) (Table 1).…”