Conjugation of latent membrane protein (LMP)-2 epitope to gold nanoparticles as highly immunogenic multiple antigenic peptides for induction of Epstein-Barr virus-specific cytotoxic T-lymphocyte responses in vitro

Bioconjug Chem. 2009 Jan;20(1):24-31. doi: 10.1021/bc800167q.

Abstract

Nasopharyngeal carcinoma is a neoplasm with a high incidence in Southeast Asia, and it is strongly associated with Epstein-Barr virus (EBV) activation involving the expression of a weakly immunogenic protein, namely, latent membrane protein (LMP)-2. Previous immunological studies already identified the human leukocyte antigen (HLA)-A11 restricted peptide epitope (SSCSSCPLSK) in the LMP-2 antigen. In this work, we prepared gold nanoparticle (AuNP)-peptide conjugate 1 by treating the nanoparticles with the N-cysteinated LMP-2 epitope. The AuNP-peptide conjugates have been characterized by TEM (15-24 nm in diameter) and UV-vis spectroscopy (surface plasmon resonance absorption band at lambda(max) = 520 nm). In the presence of a CALNN capping peptide, the AuNP-peptide conjugates are stable in solution without aggregation at room temperature for at least 48 h. By ELIspot studies, AuNP-peptide conjugate 1 was found to elicit a significantly stronger INF-gamma response [number of spot forming cells (SPC) = 727 +/- 198] from peripheral blood mononuclear cells of healthy HLA-A11 donors when compared to that induced by the unconjugated LMP-2 peptides (SFC = 73 +/- 28). Further studies showed that dendritic cells treated with conjugate 1 can effect CD8+ T-cell activation leading to epitope-specific cytotoxic T lymphocyte killing responses in vitro.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antigens, Viral / immunology*
  • CD8-Positive T-Lymphocytes / immunology
  • Cytotoxicity, Immunologic
  • Gold
  • Herpesvirus 4, Human / immunology*
  • Humans
  • Lymphocyte Activation / immunology
  • Metal Nanoparticles / chemistry*
  • T-Lymphocytes, Cytotoxic / immunology*
  • Viral Matrix Proteins / chemistry
  • Viral Matrix Proteins / immunology*

Substances

  • Antigens, Viral
  • EBV-associated membrane antigen, Epstein-Barr virus
  • Viral Matrix Proteins
  • Gold