Human papillomavirus type 16 E7 peptide-directed CD8+ T cells from patients with cervical cancer are cross-reactive with the coronavirus NS2 protein.
Human papillomavirus type 16 (HPV16) E6 and E7 oncoproteins are required for cellular transformation and represent candidate targets for HPV-specific and major histocompatibility complex class I-restricted CD8(+)-T-cell responses in patients with cervical cancer. Recent evidence suggests that cross-reactivity represents the inherent nature of the T-cell repertoire. We identified HLA-A2 binding HPV16 E7 variant peptides from human, bacterial, or viral origin which are able to drive CD8(+)-T-cell responses directed against wild-type HPV16 E7 amino acid 11 to 19/20 (E7(11-19/20)) epitope YMLDLQPET(T) in vitro. CD8(+) T cells reacting to the HLA-A2-presented peptide from HPV16 E7(11-19(20)) recognized also the HLA-A2 binding peptide TMLDIQPED (amino acids 52 to 60) from the human coronavirus OC43 NS2 gene product. Establishment of coronavirus NS2-specific, HLA-A2-restricted CD8(+)-T-cell clones and ex vivo analysis of HPV16 E7 specific T cells obtained by HLA-A2 tetramer-guided sorting from PBL or tumor-infiltrating lymphocytes obtained from patients with cervical cancer showed that cross-reactivity with HPV16 E7(11-19(20)) and coronavirus NS2(52-60) represents a common feature of this antiviral immune response defined by cytokine production. Zero of 10 patients with carcinoma in situ neoplasia and 3 of 18 patients with cervical cancer showed > or =0.1% HPV16 E7-reactive T cells in CD8(+) peripheral blood lymphocytes. In vivo priming with HPV16 was confirmed in patients with cervical cancer or preinvasive HPV16-positive lesions using HLA-A2 tetramer complexes loaded with the E6-derived epitope KLPQLCTEL. In contrast, we could not detect E6-reactive T cells in healthy individuals. These data imply that the measurement of the HPV16 E7(11-19(20)) CD8(+)-T-cell response may reflect cross-reactivity with a common pathogen and that variant peptides may be employed to drive an effective cellular immune response against HPV.
Nilges
Katja
K
Department of Medical Microbiology, University of Mainz, Germany.
Höhn
Hanni
H
Pilch
Henryk
H
Neukirch
Claudia
C
Freitag
Kirsten
K
Talbot
P J
PJ
Maeurer
Markus J
MJ
D000595:Amino Acid Sequence; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D017934:Coronavirus / Q000276:immunology; D003429:Cross Reactions; D018984:Epitopes, T-Lymphocyte / Q000276:immunology; D005260:Female; D015789:HLA-A2 Antigen / Q000378:metabolism; D006801:Humans; D008213:Lymphocyte Activation; D008969:Molecular Sequence Data; D009856:Oncogene Proteins, Viral; D027383:Papillomaviridae / Q000276:immunology*; D050725:Papillomavirus E7 Proteins; D030361:Papillomavirus Infections / Q000276:immunology; D010455:Peptides / Q000737:chemistry / Q000235:genetics / Q000276:immunology; D014412:Tumor Virus Infections / Q000276:immunology; D002583:Uterine Cervical Neoplasms / Q000276:immunology; D017361:Viral Nonstructural Proteins / Q000276:immunology
D018984:Epitopes, T-Lymphocyte; D015789:HLA-A2 Antigen; D009856:Oncogene Proteins, Viral; D050725:Papillomavirus E7 Proteins; D010455:Peptides; D017361:Viral Nonstructural Proteins; C059731:oncogene protein E7, Human papillomavirus type 16