Anthrax-protective effects of yeast beta 1,3 glucans.
BACKGROUND
The recent events increasing the threat of bioterrorism have prompted a widespread search for defenses against this peril.


OBJECTIVE
To evaluate the anthrax-protective effect of beta1,3-glucan immune modulators (PGG-glucan and WGP beta glucan) in an experimental animal model.


METHODS
Beta1,3-glucan immune modulators were administered by subcutaneous injection to Balb/c mice 2 days prior to anthrax challenge. WGP beta glucan was administered by daily oral gavage for 7 days prior to challenge, or in drinking water for 10 days postchallenge with a lethal dose of Bacillus anthracis spores. Survival, survival time, and microbial bioburden relative to an infected, untreated control group were assessed.


RESULTS
A single injected dose of PGG-glucan or WGP beta glucan immune modulators given 2 days before challenge significantly: (a) increased the survival rate of infected mice (2.5-fold), (b) diminished the bacterial load in the lungs of infected mice (4-8-fold), and (c) increased the proportion of bacteria-free animals 10 days after challenge (2-fold). In mice prophylactically administered oral WGP beta glucan for 1 week prior to infection, survival increased from 50% to 100%; therapeutic administration of oral WGP beta glucan for 10 days postinfection increased survival from 30% up to 90% in treatment groups.


CONCLUSIONS
These results demonstrate the potential for beta1,3-glucan immune modulators to provide a significant degree of protection against anthrax, a potential biological warfare (BW) agent in a mouse model of anthrax infection. Further studies are needed to optimize protection, evaluate activity in combination with other treatment options, demonstrate activity in a validated primate model of infection, and determine if protection is effective against other potential BW agents.
Kournikakis
Bill
B
Chemical and Biological Defence Section, Defence R&D Canada, Suffield, Medicine Hat, Alberta, Can
Mandeville
Rosemonde
R
Brousseau
Pauline
P
Ostroff
Gary
G
D000276:Adjuvants, Immunologic / Q000627:therapeutic use; D000818:Animals; D000881:Anthrax / Q000517:prevention & control*; D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents / Q000627:therapeutic use*; D001203:Ascomycota / Q000737:chemistry*; D001408:Bacillus anthracis / Q000187:drug effects / Q000254:growth & development; D001694:Biological Warfare; D023482:Bioterrorism; D004195:Disease Models, Animal; D005260:Female; D005936:Glucans / Q000627:therapeutic use*; D008168:Lung / Q000382:microbiology; D051379:Mice; D008807:Mice, Inbred BALB C; D015996:Survival Rate; D047071:beta-Glucans
D000276:Adjuvants, Immunologic; D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents; D005936:Glucans; D047071:beta-Glucans; C069894:poly-1-6-glucopyranosyl-1-3-glucopyranose glucan; C033363:beta-1,3-glucan