Molecular Interactions of β-(1→3)-Glucans with Their Receptors

The evaluation of β-(1 → 3)-nonaglucoside as an anti-Candida albicans immune response inducer

Synthetically prepared bovine serum albumin (BSA) conjugate of linear β-(1 → 3)-nonaglucoside ligand (G9) has been applied as a biological response immunomodulator in vivo and ex vivo. Active immunization of Balb/c mice revealed effective induction of specific humoral responses in comparison with Candida β-D-glucan and Candida whole cells. Induced post-vaccination serum exhibited a growth-inhibition effect on the multi-azole-resistant clinical strain Candida albicans CCY 29-3-164 in experimental mucocutaneous infection ex vivo. Evaluation of immune cell proliferation and the cytotoxic potential of the G9-ligand has revealed its bioavailability and an immunostimulative effect in vaccination-sensitized Balb/c mice splenocytes and RAW 264.7 macrophages.

Euglena gracilis paramylon activates human lymphocytes by upregulating pro-inflammatory factors

The aim of this study was to verify the activation details and products of human lymphomonocytes, stimulated by different β-glucans, that is Euglena paramylon, MacroGard^®, and lipopolysaccharide. We investigated the gene expression of inflammation-related cytokines and mediators, transactivation of relevant transcription factors, and phagocytosis role in cell-glucan interactions, by means of RT-PCR, immunocytochemistry, and colorimetric assay. Our results show that sonicated and alkalized paramylon upregulates pro-inflammatory factors (NO, TNF-α, IL-6, and COX-2) in lymphomonocytes. A clear demonstration of this upregulation is the increased transactivation of NF-kB visualized by immunofluorescence microscopy. Phagocytosis assay showed that internalization is not a mandatory step for signaling cascade to be triggered, since immune activity is not present in the lymphomonocytes that have internalized paramylon granules and particulate MacroGard^®. Moreover, the response of Euglena β-glucan-activated lymphomonocytes is much greater than that induced by commercially used β-glucans such as MacroGard^®. Our in vitro results indicate that linear fibrous Euglena β-glucan, obtained by sonication and alkaline treatment can act as safe and effective coadjutant of the innate immune system response.

Addition of Selenium Improves Immunomodulative Effects of Glucan

Background:

Selenium (Se) is an established essential nutrient that plays a role in various biological processes including cancer development. Similarly, stimulation of immune reactions by β-glucans is well-documented.

Aims:

In the current study, we focused on the stimulation of phagocytosis and interleukin (IL)-2 production and on potentiation of anticancer immunity by a combination of glucan with two types of Se.

Materials and Methods:

Phagocytosis was evaluated using synthetic microspheres; cancer development was measured either using breast cancer cells or using lung cancer cells.

Results:

Using two different murine models of cancer, we showed that the Se/glucan combination strongly suppressed the growth of cancer, mostly probably via stimulation of immunity.

Conclusions:

A combination of glucan with Se offers superior stimulation of immunity and inhibition of cancer growth.

Anti-hepatoma activity of the stiff branched β-d-glucan and effects of molecular weight

The water soluble β-d-glucan AF1 with short branches isolated from Auricularia auricula-judae exhibited significant anti-hepatoma activities, and it was confirmed that AF1 had stiff chains and could induce cancer cell apoptosis and anti-angiogenesis through activating immune responses.