[Dimo-thylidioctyl ammonium bromide-BCG polysaccharide nucleic acid adjuvant enhanced the immunogenicity of a Mycobacterium tuberculosis subunit vaccine].
OBJECTIVE
To investigate the activity of a novel adjuvant consisting of dimethyldioctyldecyl ammonium bromide (DDA) and BCG polysaccharide nucleic acid (BCG-PSN).


METHODS
BCG-PSN was extracted by hot-phenol method, and combined with DDA and Mycobacterium tuberculosis fusion antigen AMM (Ag85B-MPT64(190-198)-Mtb8.4) to formulate the Mycobacterium tuberculosis subunit vaccine. Mice were immunized subcutaneously with a 2-week interval between the immunizations (0.2 ml/dose), and humoral and cell-mediated immunity were detected by ELISA and ELISPOT respectively.


RESULTS
With the stimulation of Ag85B in vitro, the number of antigen specific IFN-gamma producing spleen lymphocytes were 222 +/- 79, 259 +/- 85, 230 +/- 64 per million respectively in the mice immunized with AMM + DDA + BCG-PSN, AMM + DDA, and BCG. Spleen lymphocytes in these 3 groups produced higher levels of IFN-gamma compared to the groups with the adjuvant of IFA or BCG-PSN alone or without adjuvant upon stimulation with Ag85B (t = 2.923-7.118, P < 0.05). Furthermore, the adjuvant consisting of DDA and BCG-PSN increased the ratio of Ig(2a)/IgG1 than DDA alone (0.125 vs. 0.025). Combined with AMM, the adjuvant DDA and the one consisting of DDA and BCG-PSN induced higher level of immunity than incomplete Freund's adjuvant (IFA), NaCl, and BCG-PSN alone.


CONCLUSIONS
Mycobacterium tuberculosis subunit vaccine AMM + DDA + BCG-PSN induced a strong Th1-type immune response, and DDA + BCG-PSN, especially DDA promoted the immune response of the M. tuberculosis subunit vaccine in mice.
Song
Nan-nan
NN
Lanzhou Center for Tuberculosis Research, Institute of Pathogenic Biology, School of Basic Medical Sciences, Lanzhou University, Lanzhou 730000, China.
Wang
Bing-xiang
BX
Shi
Da-zhong
DZ
Fu
Lin-feng
LF
Luo
Yu
Y
Yu
Hong-juan
HJ
Han
Shao-bo
SB
Jiao
Lei
L
Qie
Ya-qing
YQ
Wang
Hong-hai
HH
Zhang
Ying
Y
Zhu
Bing-dong
BD
D000276:Adjuvants, Immunologic; D000818:Animals; D001500:BCG Vaccine / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D009169:Mycobacterium tuberculosis / Q000276:immunology*; D032581:Tuberculosis Vaccines / Q000276:immunology*; D022223:Vaccines, Subunit / Q000276:immunology
D000276:Adjuvants, Immunologic; D001500:BCG Vaccine; D032581:Tuberculosis Vaccines; D022223:Vaccines, Subunit