Construction and immunogenicity study of a 297-bp humanized HIV V3 DNA of an approximated last common ancestor in mice.
DNA immunization represents one of the promising HIV-1 vaccine approaches. To overcome the obstacle of genetic variation, we used the last common ancestor (LCA) or "center-of-the-tree" approach to study a DNA fragment of the HIV-1 envelope surrounding the V3 region. A humanized codon of the 297-bp consensus ancestral sequence of the HIV-1 envelope (codons 291-391) was derived from the 80 most recent HIV-1 isolates from the 8 circulating HIV-1 subtypes worldwide. This 297-bp humanized "multi-clade" V3 DNA was amplified by a PCR-based technique. The PCR product was well expressed in vitro whereas the corresponding non-humanized V3 DNA (subtype A/E) could not be expressed. However, both V3 DNA constructs as well as the full-length HIV-1 envelope construct (A/E) were found to be immunogenic in mice by the footpad-swelling assay. Moreover, intracellular and extracellular interferon-gamma could be detected upon in vitro stimulation of spleen cells although the response was relatively weak. Further improvement of our humanized V3 DNA is needed.
Sirivichayakul
Sunee
S
Department of Medicine, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.
Tirawatnapong
Thaweesak
T
Ruxrungtham
Kiat
K
Oelrichs
Robert
R
Lorenzen
Sven-Lver
SL
Xin
Ke-Qin
KQ
Okuda
Kenji
K
Phanuphak
Praphan
P
D016915:AIDS Vaccines / Q000276:immunology; D000818:Animals; D004279:DNA, Viral / Q000235:genetics / Q000276:immunology*; D000939:Epitopes / Q000276:immunology; D005260:Female; D015497:HIV-1 / Q000235:genetics / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D023421:Models, Animal; D016133:Polymerase Chain Reaction; D019444:Vaccines, DNA / Q000276:immunology; D014759:Viral Envelope Proteins / Q000276:immunology
D016915:AIDS Vaccines; D004279:DNA, Viral; D000939:Epitopes; D019444:Vaccines, DNA; D014759:Viral Envelope Proteins