Cancer-testis antigen ACRBP: Cytotoxic response to its HLA-A2 restricted peptide and immune features in ovarian cancer

Hum Vaccin Immunother. 2025 Dec;21(1):2557096. doi: 10.1080/21645515.2025.2557096. Epub 2025 Oct 16.

Abstract

While our prior study identified the HLA-A *0201-restricted ACRBP epitope peptide and demonstrated its capacity to generate cytotoxic T lymphocytes (CTLs) in vitro, the clinical relevance of the peptide-induced T cell reactivity in ovarian cancer (OC) patients and the in vivo anti-tumor efficacy of these CTLs remain unexplored. In this study, dendritic cells were sensitized with ACRBP peptide (ALLVLCYSI) and co-cultured with autologous CD8+T cells to induce the production of specific cytotoxic T lymphocytes (Pep-CTLs). The anti-tumor effects of Pep-CTLs were evaluated in SCID mice bearing human ovarian cancer (OC) OVCAR-3 cells. Concurrently, we co-cultured ALLVLCYSI peptide with peripheral blood mononuclear cells (PBMCs) from OC patients (HLA-A2+, ACRBP+) and assessed the number of specific T cells using ELISPOT assays. The immunological impact of the ACRBP peptide against human OC was validated through both in vitro and in vivo experiments. These findings establish a preclinical foundationfor developing ACRBP peptide-based vaccines in OC immunotherapy. To further elucidate ACRBP's role in OC treatment, the study analyzed single-cell RNA sequencing data from 8 OC patients and bulk RNA sequencing data from the Cancer Genome Atlas Project (TCGA) comprising 308 ovarian cancer cases. This analysis aimed to explore the heterogeneity among ACRBP-expressing tumor cell populations and to investigate the correlation between ACRBP expression and immune molecule expression (including MHC and chemokines) alongside chemotherapy response. These insights furnish a theoretical framework supporting the future application of ACRBP in tumor immunotherapy and strategies to prevent immune escape.

Keywords: ACRBP; CTL; Cancer-testis antigen; ovarian cancer.

MeSH terms

  • Animals
  • Antigens, Neoplasm* / immunology
  • CD8-Positive T-Lymphocytes / immunology
  • Cell Line, Tumor
  • Coculture Techniques
  • Dendritic Cells / immunology
  • Disease Models, Animal
  • Female
  • HLA-A2 Antigen* / immunology
  • Humans
  • Mice
  • Mice, SCID
  • Ovarian Neoplasms* / immunology
  • Ovarian Neoplasms* / therapy
  • T-Lymphocytes, Cytotoxic* / immunology

Substances

  • HLA-A2 Antigen
  • Antigens, Neoplasm