Protective effect of beta-glucan against mycobacterium bovis, BCG infection in BALB/c mice.
Beta-1,3-glucan is a potent stimulator of macrophage functions and has a protective effect against a range of infections in rodent models. We examined whether the agent could also protect against the intracellular Mycobacterium bovis, bacillus Calmette-Guérin (BCG) infection in mice. BCG-susceptible BALB/c mice were injected intravenously (i.v.) with beta-glucan or vehicle 3 days before, or with beta-glucan 7 days after i.v. challenge with live BCG bacilli. The animals were killed 4 or 8 weeks later, their organs were homogenized and applied to object slides and stained with auramin for counting of bacilli, or seeded onto agar in Petri dishes. Mice treated with beta-glucan both pre- and postchallenge had significantly lower numbers of BCG bacilli and BCG colony-forming units in spleen homogenates compared with controls 4 weeks after challenge. A similar, but not statistically significant, tendency was observed in spleen homogenates from mice killed 8 weeks after challenge. In homogenates of liver and lungs there were similar findings, but less pronounced. There was a dose-dependent effect of beta-glucan injected before BCG challenge on the number of BCG bacilli found in spleen and liver homogenates. In addition, antibody cross-reactivity was demonstrated between M. tuberculosis cell wall and beta-glucan. The results suggest that beta-glucan has a protective effect against M. bovis, BCG infection in susceptible mice.
Hetland
G
G
Institute of Immunology and Rheumatology, The National Hospital, Oslo, Norway.
Løvik
M
M
Wiker
H G
HG
D000818:Animals; D000942:Antigens, Bacterial / Q000276:immunology; D000995:Antitubercular Agents / Q000276:immunology / Q000494:pharmacology*; D002473:Cell Wall; D015169:Colony Count, Microbial; D003429:Cross Reactions; D004195:Disease Models, Animal; D005260:Female; D005936:Glucans / Q000276:immunology / Q000494:pharmacology*; D007275:Injections, Intravenous; D008099:Liver / Q000382:microbiology / Q000473:pathology; D008168:Lung / Q000382:microbiology / Q000473:pathology; D051379:Mice; D008807:Mice, Inbred BALB C; D009163:Mycobacterium bovis / Q000187:drug effects* / Q000276:immunology; D013154:Spleen / Q000382:microbiology / Q000473:pathology; D014376:Tuberculosis / Q000276:immunology / Q000473:pathology / Q000517:prevention & control*; D047071:beta-Glucans
D000942:Antigens, Bacterial; D000995:Antitubercular Agents; D005936:Glucans; D047071:beta-Glucans; C033363:beta-1,3-glucan