Vaccine-induced immune responses in rodents and nonhuman primates by use of a humanized human immunodeficiency virus type 1 pol gene.
A synthetic gene consisting of the reverse transcriptase (RT) and integrase (IN) domains of human immunodeficiency virus type 1 (HIV-1) pol was constructed using codons most frequently used in humans. The humanized pol gave dramatically improved levels of Rev-independent, in vitro protein production in mammalian cells and elicited much stronger cellular immunity in rodents than did virus-derived gene. Specifically, BALB/c mice were immunized with plasmids and/or recombinant vaccinia virus constructs expressing the synthetic gene. High frequencies of Pol-specific T lymphocytes were detected in these animals by the gamma interferon enzyme-linked immunospot assay against pools of short overlapping peptides. Characterization of the stimulatory peptides from these pools indicates that the optimized gene constructs are able to effectively activate both CD4+ and CD8+ T cells. Immunization of rhesus macaques with DNA vaccines expressing the humanized pol coupled to a human tissue plasminogen activator leader sequence led to pronounced in vitro cytotoxic T-lymphocyte killing activities and enhanced levels of circulating Pol-specific T cells, comparable to those observed in HIV-1-infected human subjects. Thus, optimizing the immunogenic properties of HIV-1 Pol at the level of the gene sequence validates it as an antigen and provides an important step toward the construction of a potent pol-based HIV-1 vaccine component.
Casimiro
Danilo R
DR
Department of Virus and Cell Biology, Merck Research Laboratories, Merck and Company, West Point, Pennsylvania 19486, USA.
Tang
Aimin
A
Perry
Helen C
HC
Long
Romnie S
RS
Chen
Minchun
M
Heidecker
Gwendolyn J
GJ
Davies
Mary-Ellen
ME
Freed
Daniel C
DC
Persaud
Natasha V
NV
Dubey
Sheri
S
Smith
Jeffrey G
JG
Havlir
Diane
D
Richman
Douglas
D
Chastain
Michael A
MA
Simon
Adam J
AJ
Fu
Tong-Ming
TM
Emini
Emilio A
EA
Shiver
John W
JW
D016915:AIDS Vaccines / Q000008:administration & dosage* / Q000276:immunology; D000595:Amino Acid Sequence; D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D002452:Cell Count; D015751:Genes, pol / Q000276:immunology*; D015497:HIV-1 / Q000235:genetics / Q000276:immunology*; D006801:Humans; D007114:Immunization; D008253:Macaca mulatta; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D010957:Plasmids; D013154:Spleen / Q000166:cytology / Q000276:immunology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D013997:Time Factors; D019444:Vaccines, DNA / Q000008:administration & dosage* / Q000276:immunology; D014614:Vaccines, Synthetic / Q000008:administration & dosage / Q000276:immunology
D016915:AIDS Vaccines; D019444:Vaccines, DNA; D014614:Vaccines, Synthetic