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.
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.
Cheung
Wai-Hung
WH
Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong.
Chan
Vera Sau-Fong
VS
Pang
Heung-Wing
HW
Wong
Man-Kin
MK
Guo
Zhi-Hong
ZH
Tam
Paul Kwong-Hang
PK
Che
Chi-Ming
CM
Lin
Chen-Lung
CL
Yu
Wing-Yiu
WY
D000956:Antigens, Viral / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D003602:Cytotoxicity, Immunologic; D006046:Gold; D004854:Herpesvirus 4, Human / Q000276:immunology*; D006801:Humans; D008213:Lymphocyte Activation / Q000276:immunology; D053768:Metal Nanoparticles / Q000737:chemistry*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D014763:Viral Matrix Proteins / Q000737:chemistry / Q000276:immunology*
D000956:Antigens, Viral; C037662:EBV-associated membrane antigen, Epstein-Barr virus; D014763:Viral Matrix Proteins; D006046:Gold