Development of vaccines and passive immunotherapy against SARS coronavirus using mouse and SCID-PBL/hu mouse models.

We have investigated novel vaccines strategies against severe acute respiratory syndrome (SARS) CoV infection using cDNA constructs encoding the structural antigens; spike (S), membrane (M), envelope (E), or nucleocapsid (N) protein, derived from SARS CoV (strain HKU39849, TW1, or FFM-1). As SARS-CoV is thought to infect the alveolar epithelial cell of the lung,in the present study, a type II alveolar epithelial cell clone, T7, was used to analyze the mechanism of CTL against SARS CoV membrane antigens. Mice vaccinated with SARS CoV (N) DNA or (M) DNA using pcDNA 3.

DNA vaccine using hemagglutinating virus of Japan-liposome encapsulating combination encoding mycobacterial heat shock protein 65 and interleukin-12 confers protection against Mycobacterium tuberculosis by T cell activation.

We investigated the immunogenicity and protective efficacy of DNA vaccine combinations expressing mycobacterial heat shock protein 65 (Hsp65) and interleukin-12 (IL-12) using gene gun bombardment and the hemagglutinating virus of Japan (HVJ)-liposome method. A mouse IL-12 expression vector (mIL-12 DNA) encoding single-chain IL-12 proteins comprised of p40 and p35 subunits were constructed. In a mouse model, a single gene gun vaccination with the combination of Hsp65 DNA and mIL-12 DNA provided a remarkably high degree of protection against challenge with virulent Mycobacterium tuberculosis; bacterial numbers were 100-fold lower in the lungs compared to BCG-vaccinated mice.

The development of vaccines against SARS corona virus in mice and SCID-PBL/hu mice.

We have investigated to develop novel vaccines against SARS CoV using cDNA constructs encoding the structural antigen; spike protein (S), membrane protein (M), envelope protein (E), or nucleocapsid (N) protein, derived from SARS CoV. Mice vaccinated with SARS-N or -M DNA using pcDNA 3.1(+) plasmid vector showed T cell immune responses (CTL induction and proliferation) against N or M protein, respectively.

Novel recombinant BCG and DNA-vaccination against tuberculosis in a cynomolgus monkey model.

We have developed two novel tuberculosis (TB) vaccines: a DNA vaccine combination expressing mycobacterial heat shock protein 65 (Hsp65) and interleukin-12 (IL-12) by using the hemagglutinating virus of Japan (HVJ)-liposome (HSP65+IL-12/HVJ) and a recombinant BCG harboring the 72f fusion gene (72f rBCG). These vaccines provide remarkable protective efficacy in mouse and guinea pig models, as compared to the current by available BCG vaccine. In the present study, we extended our studies to a cynomolgus monkey model, which is currently the best animal model of human tuberculosis, to evaluate the HSP65+IL-12/HVJ and 72f rBCG vaccines.