Dominant recognition by human CD8+ cytotoxic T lymphocytes of dengue virus nonstructural proteins NS3 and NS1.2a.
A severe complication of dengue virus infection, dengue hemorrhagic fever (DHF), is hypothesized to be immunologically mediated and virus-specific cytotoxic T lymphocytes (CTLs) may trigger DHF. It is also likely that dengue virus-specific CTLs are important for recovery from dengue virus infections. There is little available information on the human CD8+ T cell responses to dengue viruses. Memory CD8+CTL responses were analyzed to determine the diversity of the T cell response to dengue virus and to identify immunodominant proteins using PBMC from eight healthy adult volunteers who had received monovalent, live-attenuated candidate vaccines of the four dengue serotypes. All the donors had specific T cell proliferation to dengue and to other flaviviruses that we tested. CTLs were generated from the stimulated PBMC of all donors, and in the seven donors tested, dengue virus-specific CD8+CTL activity was demonstrated. The nonstructural (NS3 and NS1.2a) and envelope (E) proteins were recognized by CD8+CTLs from six, five, and three donors, respectively. All donors recognized either NS3 or NS1.2a. In one donor who received a dengue 4 vaccine, CTL killing was seen in bulk culture against the premembrane protein (prM). This is the first demonstration of a CTL response against the prM protein. The CTL responses using the PBMC of two donors were serotype specific, whereas all other donors had serotype-cross-reactive responses. For one donor, CTLs specific for E, NS1.2a, and NS3 proteins were all HLA-B44 restricted. For three other donors tested, the potential restricting alleles for recognition of NS3 were B38, A24, and/or B62 and B35. These results indicate that the CD8+CTL responses of humans after immunization with one serotype of dengue virus are diverse and directed against a variety of proteins. The NS3 and NS1.2a proteins should be considered when designing subunit vaccines for dengue.
Mathew
A
A
Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Medical Center, Worcester 01655, USA.
Kurane
I
I
Rothman
A L
AL
Zeng
L L
LL
Brinton
M A
MA
Ennis
F A
FA
D000328:Adult; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D002478:Cells, Cultured; D003716:Dengue Virus / Q000276:immunology*; D005416:Flavivirus / Q000276:immunology; D006680:HLA Antigens; D015395:Histocompatibility Antigens Class I; D006801:Humans; D016056:Immunodominant Epitopes; D007156:Immunologic Memory; D008213:Lymphocyte Activation; D020365:RNA Helicases; D012697:Serine Endopeptidases; D012703:Serotyping; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D017361:Viral Nonstructural Proteins / Q000276:immunology*; D014765:Viral Vaccines / Q000276:immunology*; D043583:Nucleoside-Triphosphatase; D053487:DEAD-box RNA Helicases; D000085242:Viral Proteases
D006680:HLA Antigens; D015395:Histocompatibility Antigens Class I; D016056:Immunodominant Epitopes; D020365:RNA Helicases; D012697:Serine Endopeptidases; D017361:Viral Nonstructural Proteins; D014765:Viral Vaccines; C060028:NS3 protein, flavivirus; D043583:Nucleoside-Triphosphatase; D053487:DEAD-box RNA Helicases; D000085242:Viral Proteases