Recent Progress in the Field of β-(1,3)-Glucans and New Applications

Abstract

Beta-(1,3)-glucans are widely distributed within microorganisms or seaweeds in which they act as membrane components or for energy storage, respectively. Since these glucans are not biosynthesized by mammals, they are likely to activate the immune system of their host. Since the discovery of their positive involvement as immunomodulator agents, numerous studies were published all around the glycosciences. These works deal with purification procedures, analytical chemistry, synthetic processes, chemical modification of the natural polysaccharides, determination of their physicochemical properties, and assessment of their biological and medicinal effects through in vitro and in vivo studies. This article aims at presenting some recent results linked to beta-(1,3)-glucans through two closely connected points of view, i.e. biology and chemistry. Biological aspects will be focused more particularly on discovery of some receptors present on immunocompetent cells and scope and limitations of chemical synthesis and/or modifications will be described. Moreover, this paper will also introduce some new chemo-enzymatic synthetic methods using wild-type or mutant glycosidases and will be extended to novel opportunities of applications of beta-(1,3)-glucans in nanotechnology resulting from a better understanding of their self-assembling propensity in aqueous media.

β-Glucans, History, and the Present: Immunomodulatory Aspects and Mechanisms of Action

“…A general solution is the binding of short oligomers of glucose containing β(1→3) and β(1→6) linkages to a polymer carrier of defined size and structure. A reasonable assumption is that such "synthetic" β-glucans will interact with receptors of immunocompetent cells and elicit analogous reactions as natural β-glucan (Descroix et al, 2006). From the immunopharmacological point of view, such probes would eventually replace the natural β-glucan.…”

Intestinal and Systemic Immune Development and Response to Vaccination Are Unaffected by Dietary (1,3/1,6)-β- d -Glucan Supplementation in Neonatal Piglets

“…They boost the natural defense mechanisms of the adult host by stimulating both innate (16) and adaptive (1) immune responses. ␤G are recognized by the pattern recognition receptors of the innate immune system (13). At least four receptors have been identified for the recognition of ␤G: complement receptor 3, lactosylceramide, scavenger receptors, and dectin-1, the latter of which is considered the most important ␤G receptor (16,40).…”

Differential Adjuvant Effects of Soluble Beta Glucans from Barley and Saccharomyches Cerevisia in Primary and Secondary Humoral Immune Responses

“…17 Now, we know that CR3 on neutrophils and natural killer cells plays very important roles in ß-glucan-mediated immune responses. [18][19] Additionally, other cell surface molecules such as dectin-1, lactosylceramide (CDw17), some scavenger receptors, and Toll-like receptor 2/6 (TLR2/6) are among those for ß-glucans. [20][21][22][23][24] Binding of ß-glucans to those receptors individually or in combinations initiates a serious of methabolic events including NF-κB or NF-κB-like nuclear transcription factor resulting in phagocytosis, degranulation of particules, and production of chemokines and cytokines depending on the activated cell type.…”

“…[1][2][3] Extensive studies concerning their immunomodulatory role particularly on the innate immune system have been accomplished so far. [4][5] However, characteristics of specific antibody responses augmented by ß-glucans with different features have been poorly understood.…”