epiglucan and Orthomyxoviridae-Infections

Influenza virus is a serious health concern. β-glucans derived from plants, bacteria, and fungi have been shown to potentiate immune system responses including those elicited by vaccination. However, in these studies β-glucan was administered as an adjuvant in the vaccine preparation. We hypothesized that addition of a commercially available whole glucan particle supplement to the diet would improve immune response to primary and secondary influenza vaccination in mice. β-glucan was added to pelleted diet and fed to mice at concentrations designed to deliver 0 (control), 1.8 or 90 mg·kg(-1)·day(-1) to each mouse. Influenza vaccine was given intramuscularly in the left hindlimb and primary and secondary responses were assessed. Supplementation with β-glucan was not effective in boosting immune responses to the vaccine, either in the primary or secondary vaccination experiments. Surprisingly, addition of particulate β-glucan to the vaccine itself also failed to elicit a greater antibody response. These observations suggest that this particular form of β-glucan is ineffective in boosting immune response to intramuscular influenza vaccination. Further study is warranted to determine if the use of different mouse models, different vaccine delivery systems, or β-glucans purified from different strains of bacteria, fungi, or plants could improve outcomes using this or similar protocols.

Topics: Animals; Antibodies, Viral; Antibody Formation; beta-Glucans; Cells, Cultured; Cytokines; Dietary Supplements; Immunity, Cellular; Immunization, Secondary; Influenza A virus; Influenza Vaccines; Mice; Mice, Inbred BALB C; Orthomyxoviridae Infections; Vaccination

β-(1→3)-D-glucans with β-(1→6)-glycosidic linked branches produced by mushrooms, yeast and fungi are known to be an immune activation agent, and are used in anti-cancer drugs or health-promoting foods. In this report, we demonstrate that oral administration of Aureobasidium pullulans-cultured fluid (AP-CF) enriched with the β-(1→3),(1→6)-D-glucan exhibits efficacy to protect mice infected with a lethal titer of the A/Puerto Rico/8/34 (PR8; H1N1) strain of influenza virus. The survival rate of the mice significantly increased by AP-CF administration after sublethal infection of PR8 virus. The virus titer in the mouse lung homogenates was significantly decreased by AP-CF administration. No significant difference in the mRNA expression of inflammatory cytokines, and in the population of lymphocytes was observed in the lungs of mice administered with AP-CF. Interestingly, expression level for the mRNA of virus sensors, RIG-I (retinoic acid-inducible gene-I) and MDA5 (melanoma differentiation-associated protein 5) strongly increased at 5 hours after the stimulation of A. pullulans-produced purified β-(1→3),(1→6)-D-glucan (AP-BG) in murine macrophage-derived RAW264.7 cells. Furthermore, the replication of PR8 virus was significantly repressed by pre-treatment of AP-BG. These findings suggest the increased expression of virus sensors is effective for the prevention of influenza by the inhibition of viral replication with the administration of AP-CF.

Topics: Administration, Oral; Animals; Ascomycota; beta-Glucans; Cell Line; Culture Media, Conditioned; Cytokines; DEAD-box RNA Helicases; Gene Expression Regulation; Immunization; Influenza A Virus, H1N1 Subtype; Intercellular Signaling Peptides and Proteins; Interferon-Induced Helicase, IFIH1; Lung; Macrophages; Male; Membrane Proteins; Mice; Nerve Tissue Proteins; Orthomyxoviridae Infections; Receptors, Cell Surface; Survival Rate; Time Factors

The paper presents experimental findings of the combined antiinfluenza drug (inactivated influenza vaccine + an interferon inducer - an immunogenetic anstimulator - polysaccharide 1,3beta-glucan). The oral immunization with the drug induces antibody accumulation in the secretions of the upper airway and blood sera in defense titers, interferon synthesis at days 1-3 postadministration, forms murine resistance to infection with homologous and heterologous viruses, enhances the functional activity of alveolar macrophages.

Topics: Administration, Oral; Animals; beta-Glucans; Drug Combinations; Drug Evaluation, Preclinical; Glucans; Immunity, Innate; Immunization; Influenza A virus; Influenza Vaccines; Interferon Inducers; Male; Mice; Orthomyxoviridae Infections; Vaccines, Inactivated