Identification of HLA-A*2402-restricted HCMV immediate early-1 (IE-1) epitopes as targets for CD8+ HCMV-specific cytotoxic T lymphocytes.
BACKGROUND
To identify novel HLA-A*2402-restricted human cytomegalovirus (HCMV) immediate early-1 (IE-1) epitopes for adoptive immunotherapy, we explored 120 overlapping 15-amino acid spanning IE-1.


METHODS
These peptides were screened by measuring the frequency of polyclonal CD8+ T cells producing intracellular interferon-gamma (IFN-gamma) using flow cytometry and the epitopes were validated with a HCMV-infected target Cr release cytotoxicity assay.


RESULTS
Initial screening was performed with 12 mini-pools of 10 consecutive peptides made from 120 overlapping peptides15-amino acids in length that spanned IE-1. When peripheral blood mononuclear cells (PBMCs) from HLA-A*2402 HCMV-seropositive donors were sensitized with each of the 12 mini-pools, mini-pools 1 and 2 induced the highest frequency of CD8+ cytotoxic T lymphocytes (CTLs) producing IFN-gamma. When PBMCs were stimulated with each of the twenty peptides belonging to mini-pools 1 and 2, peptides IE-11-15MESSAKRKMDPDNPD and IE-15-19AKRKMDPDNPDEGPS induced the greatest quantities of IFN-gamma production and cytotoxicity of HLA-matched HCMV-infected fibroblasts. To determine the exact HLA-A*2402-restricted epitopes within the two IE-1 proteins, we synthesized a total of twenty-one overlapping 9- or 10 amino acid peptides spanning IE-11-15 and IE-15-19. Peptide IE-13-12SSAKRKMDPD induced the greatest quantities of IFN-gamma production and target cell killing by CD8+ CTLs.


CONCLUSIONS
HCMV IE-13-12SSAKRKMDPD is a HLA-A*2402-restricted HCMV IE-1 epitope that can serve as a common target for CD8+ HCMV-specific CTLs.
Lim
Jong-Baeck
JB
Department of Transfusion Medicine, Warren G, Magnuson Clinical Center, National Institutes of Health, Bethesda, MD, USA. jlim@yumc.yonsei.ac.kr
Kim
Hyun Ok
HO
Jeong
Seok Hoon
SH
Ha
Joo Eun
JE
Jang
Sunphil
S
Lee
Sang-Guk
SG
Lee
Kyungwon
K
Stroncek
David
D
D000595:Amino Acid Sequence; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology* / Q000821:virology; D002460:Cell Line; D003587:Cytomegalovirus / Q000276:immunology*; D003586:Cytomegalovirus Infections / Q000276:immunology / Q000628:therapy; D000939:Epitopes / Q000235:genetics / Q000276:immunology*; D005347:Fibroblasts / Q000166:cytology / Q000276:immunology; D015234:HLA-A Antigens / Q000276:immunology*; D059871:HLA-A24 Antigen; D006801:Humans; D017874:Immediate-Early Proteins / Q000235:genetics / Q000276:immunology*; D007371:Interferon-gamma / Q000276:immunology; D008969:Molecular Sequence Data; D010455:Peptides / Q000235:genetics / Q000276:immunology; D016176:T-Lymphocyte Subsets / Q000276:immunology* / Q000821:virology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology* / Q000821:virology; D014764:Viral Proteins / Q000235:genetics / Q000276:immunology
D000939:Epitopes; D015234:HLA-A Antigens; C438506:HLA-A*24:02 antigen; D059871:HLA-A24 Antigen; D017874:Immediate-Early Proteins; D010455:Peptides; D014764:Viral Proteins; D007371:Interferon-gamma
J Immunol. 2000 Oct 1;165(7):4105-11
11034422
Eur J Immunol. 2000 Jun;30(6):1676-82
10898504
Biol Blood Marrow Transplant. 2008 Oct;14(10):1156-1162
18804046
J Virol. 2003 May;77(9):5226-40
12692225
Blood. 2002 Jun 1;99(11):3916-22
12010789
Nat Med. 2006 Oct;12(10):1160-6
16998485
Blood. 2001 Aug 1;98(3):505-12
11468143
Br J Haematol. 2003 May;121(3):428-38
12716365
N Engl J Med. 1982 Jul 1;307(1):7-13
6281647
Hum Immunol. 2004 May;65(5):550-7
15172456
Science. 1992 Jul 10;257(5067):238-41
1352912
J Immunother. 2002 Jul-Aug;25(4):342-51
12142557
Exp Hematol. 2006 Mar;34(3):296-307
16543064
J Immunol. 2007 Apr 1;178(7):4455-65
17372003
J Infect Dis. 2000 Sep;182(3):937-40
10950793
Cytometry A. 2004 Mar;58(1):79-86
14994226
J Exp Med. 2005 Apr 4;201(7):1031-6
15795239
J Immunol. 1994 Apr 15;152(8):3913-24
8144960
Hum Gene Ther. 2000 Jul 1;11(10):1453-63
10910142
Blood. 2001 Feb 15;97(4):994-1000
11159528
J Exp Med. 2005 Aug 1;202(3):379-86
16061727
J Transl Med. 2007 Mar 28;5:17
17391521
Blood. 2004 May 1;103(9):3565-72
14670917
J Immunol. 2004 Feb 15;172(4):2256-64
14764694
J Immunol. 1994 Jan 1;152(1):163-75
8254189
Immunogenetics. 1999 Nov;50(3-4):213-9
10602881
Proc Soc Exp Biol Med. 1956 Jun;92(2):418-24
13350367
Blood. 1994 Apr 1;83(7):1971-9
8142663
J Virol. 1996 Nov;70(11):7569-79
8892876
J Virol. 1999 Oct;73(10):8179-84
10482568
N Engl J Med. 1995 Oct 19;333(16):1038-44
7675046
Hum Immunol. 1996 Dec;51(2):95-8
8960911
Bone Marrow Transplant. 2000 Apr;25(7):757-63
10745262