epiglucan and Infections

To examine the recent scientific literature on the immune modulating effects of β-glucans and subsequent benefits on infection and cancer.. β-Glucans have been investigated for their ability to protect against infection and cancer and more recently for their therapeutic potential when combined with cancer therapy. Their immune modulating effects are attributed to the ability to bind to pattern recognition receptors including complement receptor 3, scavenger receptors, lactosylceramide, and dectin-1 that results in activation of different aspects of the immune response depending on the cell types and species involved although there is some controversy about the relative importance of each of these receptors. Most of the available evidence comes from preclinical data and human studies are just now beginning to appear in the literature, therefore firm conclusions on its clinical importance cannot yet be made. Perhaps the most promising evidence to date in human trials has come from recent studies on a benefit of β-glucan on quality of life and survival when given in combination with cancer treatment. We identify the need for future studies that compare purified forms of β-glucans from different sources to further the understanding of the mechanisms of action and aid in the development of clinical studies.. β-Glucans appear to be effective at enhancing immune function and reducing susceptibility to infection and cancer. A better understanding of the mechanisms of β-glucan recognition and subsequent immune activation is necessary for the design of effective treatment approaches in future clinical trials.

Topics: Animals; beta-Glucans; Humans; Immune System; Immunologic Factors; Infections; Neoplasms

Beta-glucan is a polysaccharide in the form of fiber and the main element of fiber in grains such as barley, oats, yeast and mushrooms. Many studies have examined the efficacy of beta-glucan in terms of the lipid lowering effects, blood sugar reduction, weight reduction, immune modulator, and anticarcinogenic effect. However, there is no comprehensive review article on the biomedical issues regarding beta-glucan. The authors searched for systematic reviews and clinical experiments for each relevant topic and reviewed the biomedical effects of beta-glucan, for the purpose of developing research strategies for the future.

Topics: Animals; Anticholesteremic Agents; beta-Glucans; Blood Glucose; Body Weight; Cholesterol; Dietary Fiber; Dietary Supplements; Dose-Response Relationship, Drug; Humans; Infections; Neoplasms

The safety and efficacy of PGG-glucan in surgical patients at high risk for postoperative infection who underwent major thoracic or abdominal surgery were determined.. Recent studies have reported a 25% to 27% infectious complication rate in patients undergoing major surgery with an average cost per infected patient of $12,000. The efficacy of PGG-glucan pretreatment in prevention of sepsis has been demonstrated in rodent models for gram-negative and gram-positive bacterial and yeast infections. In vitro studies have demonstrated enhanced microbial killing by monocytes and neutrophils in healthy volunteers after PGG-glucan administration. Thus, PGG-glucan may play a role in decreasing the infectious complication rate in patients undergoing major surgery.. A double-blind, placebo-controlled randomized study was performed in 34 high-risk patients undergoing major abdominal or thoracic surgery.. There were no adverse drug experiences associated with PGG-glucan infusion. Patients who received PGG-glucan had significantly fewer infectious complications (3.4 infections per infected patient vs. 1.4 infections per infected patient, p = 0.05), decreased intravenous antibiotic requirement (10.3 days vs. 0.4 days, p = 0.04) and shorter intensive care unit length of stay (3.3 days vs. 0.1 days, p = 0.03).. PGG-glucan is safe and appears to be effective in the further reduction of the morbidity and cost of major surgery.

Topics: Abdomen; Adjuvants, Immunologic; Aged; beta-Glucans; Double-Blind Method; Follow-Up Studies; Glucans; Humans; Infections; Middle Aged; Postoperative Complications; Premedication; Risk Factors; Thoracic Surgery

beta-Glucans are conserved glucose polymers found in the cell walls of plants, fungi, yeasts and bacteria. They have the capacity to activate innate immunity, thereby enhancing defence barriers. Besides differences in type of linkage and branching, beta-glucans can vary in solubility, molecular mass, tertiary structure, polymer charge and solution conformation. All these characteristics may influence their immunomodulating effects. In this study, the effect of seven beta-glucans that differed in origin (fungi, yeast, seaweed, bacteria or algae) and structure (linear or branched; soluble, gel or particulate) were tested on peripheral blood mononuclear cells (PBMC) and neutrophils of the pig. We looked at lymphocyte proliferation, reactive oxygen species (ROS), production by neutrophils and monocytes and cytokine production. The soluble beta-glucans Laminarin and Sleroglucan did not activate ROS-production of monocytes and neutrophils while the particulate beta-glucans (beta-glucan from algae (Euglena gracilis)) and glucan preparations from baker's yeast (Macrogard, Saccharomyces cerevisiae and Zymosan) had a stimulating effect. The highest stimulation of lymphocyte proliferation occurred by Curdlan (bacteria), Zymosan and the beta-glucan of E. gracilis, especially at high concentrations (200 microg/ml and 800 microg/ml). TNF-alpha was particularly stimulated by Macrogard and S. cerevisiae, while all beta-glucans (except Laminarin) induced IL-1beta. Furthermore, it was interesting that all beta-glucans and in particular Curdlan, gave rise to IL-10 secretion, whereas any beta-glucan induced the release of IL-8, IL-4, IL-12, IL-6 or IFN-gamma.

Topics: Adjuvants, Immunologic; Animals; beta-Glucans; Cell Proliferation; Cytokines; Immunity, Innate; In Vitro Techniques; Infection Control; Infections; Leukocytes; Lymphocytes; Molecular Structure; Monocytes; Neutrophils; Reactive Oxygen Species; Swine; Swine Diseases

We recently elucidated the structure of a highly branched 1,3-beta-D-glucan with 6-monoglucopyranosyl side chains, extracted from Aureobasidium pullulans (AP-FBG). Although the biological effects of beta-D-glucans are known to depend on their structures, the effects of a highly branched 1,3-beta-D-glucan on the production of cytokines by leukocytes in mice have not yet been elucidated. In this study, we found that AP-FBG strongly induced the production of various cytokines, especially Th1 cytokines (e.g., IFN-gamma and IL-12p70) and Th17 cytokines (e.g., IL-17A), but did not induce the production of IL-4, IL-10, and TNF-alpha in DBA/2 mouse-derived splenocytes in vitro.

Topics: Animals; beta-Glucans; Cells, Cultured; Cytokines; Fungi; Immunization; Infections; Male; Mice; Mice, Inbred C57BL; Mice, Inbred DBA; Neoplasms; Spleen; Th1 Cells

Topics: Adjuvants, Immunologic; beta-Glucans; Carbohydrates; Communicable Diseases; Glucans; Humans; Infections; Polymers