Preliminary evaluation of immunoadjuvant activity of an orally administered glucan extracted from Candida albicans

The immunoadjuvant activity of an orally administered glucan (Glucanil, Gluimmun) was investigated in mice. Glucan was extracted from Candida albicans ATCC 20955 and purified by an alkali-acid and detergent treatment. In this study the chronic intravenous infection with Candida albicans (treated or not with amphotericin B) or Staphylococcus aureus was the experimental model. Moreover the production of interleukin-2 was evaluated in treated animals. Oral treatment with glucan at 1 mg/mouse/day repeated doses, starting from 10 days before the experimental infection, significantly increased polymorphonuclear leukocytes and peripheral monocytes number. A significant increase in number and in vitro candidacidal activity was also observed for alveolar macrophages. The resistance towards systemic infection with Candida albicans or Staphylococcus aureus increased, significantly reducing the growth of microorganisms in the kidneys of infected animals. Glucan significantly increased the candidacidal spleen cells activity and synergized with amphotericin B chemotherapeutic action. Higher doses (eg. 2 or 5 mg/mouse) were not effective. A 10 days oral treatment with 1 mg/mouse/d significantly increased the interleukin-2 production. Toxicological studies showed that glucan is highly tolerated.