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WHAT IS BETA 1,3/1,6-D-GLUCAN
Beta glucans are extracted from the common baker’s yeast Saccharomyces
cervislae and composed of chains of 20-30 glucose units with side
chains of beta 1,3 and beta 1,6 linked D-glucose molecules. The
overall effect is that of a tree with a trunk, and conditions to yield
pure glucans with their unique structures preserved for mzximum
interaction and activation of immune cells. These products contain no
yeast cells, are completely safe and have no toxic side effects.
HOW BETA GLUCANS ACTIVATE THE IMMUNE SYSTEM
In the 1960’s Nicholas DiLuzio and his collaborators published a
number of papers That described the broad spectrum anti bacterial and
tumor inhibitory activity of beta glucans. These observations were
attributed to augmented host immune defense by mechanisms involving
macrophage or phagocyte activation. Phagocytes (monocytes,
macrophages, granulocytes), natural killer cells, dendritic cells, and
langrehans cells of skin bear specific receptor sites termed dectin-1
(betaGR) that bind beta 1,3 and or beta 1,6 glucans. Phagocytes also
express a whole range of receptors that recognize and bind to foreign
invaders, such as microbes, viruses, yeasts, parasites and possibly
even neoplastic cells. Binding to certain organisms is also
facilitated by recognizing serum opsonins or antibodies that have been
deposited on their surface. Once the cell receptor binds beta glucans,
immune activity is initiated. Activated macrophages undergo
morphologic and physiologic changes that result in enhanced phagocytic
(scavenger) activity, release certain cytokines or hormone messengers
that engage both innate and acquired immune system (see transfer
factor). Such cytokines as tumor necrosis factor alpha, interleukin-1
beta and granulocyte – macrophage colony stimulating factor and
others profoundly affect local and systemic immunity.
IMMUNO-PHYSIOLOGIC EFFECTS OF BETA GLUCAN ADMINISTRATION
Host Immune Response:
The administration of purified yeast glucan to a host rapidly results
in an augmented state of hose resistance to a diverse range of
microbial pathogens and possibly neoplastic cells. Prior to
establishment of such resistance, surface receptors, Dectin-1 on
macrophages, monocytes neutrophils, dedritic cells and subpopulation
of T cells recognize and bind beta glucan. Lung (alveolar)
macrophages, like inflammatory macrophages exhibit the highest surface
expression of Dectin-1 (beta GR) glucan receptor and provide an
important mechanism for internalization and clearance of particulate
pathogenic targets. This indicates a role for the receptor in immune
surveillance and control of disease. Yeast type beta glucans are also
potent biologic response modifiers. They markedly augment host
resistance to a variety of biologic insults by eliciting a cascade of
stimulatory events initiated by mononuclear phagocytes. Upon
interaction and binding of beta glucan, macrophages produce bactericidal compounds like Iysozyne, reactive
oxygen radicals and nitric oxide. In addition, these cells start
producing a number of inflammatory cystokines that will interact with
the surrounding macrophages and lymphocytes to initiate local and
acquired specific immunity. Some of these cytokines are interleukin-1,
interleukin-6, and tumor necrosis factor alpha.
Interleukin-1:
Upon binding and phagocytosis of glucan by macrophages, these cells
release interleukin-1 (IL-1) an immune systems messenger. IL-1 alpha
and IL-1 beta are two similar polypeptides involved in inflammatory
reactions.
Interleukins-6:
Interleukins-6 is a multifunctional protein that plays important roles
in host defense, acute phase reactions, immune response and
hematopoiesis or production of blood cells.
Tumor Necrosis Factor Alpha:
Under experimental conditions, mice administered beta glucan produce
tumor necrosis factor (TNF-alpha) in their peritoneal macrophages.
Similarly human monocytes stimulated with beta glucan in culture
produce TNF-alpha. Studies implicate binding of Dectin-1 the
macrophage receptor in production of TNF-alpha, a critical step required for the successful control of many
pathogens.
Effect of beta glucan On Antibiotic Therapy:
Beta glucan redness need and potentiates antibiotic therapy. When beta
glucan was added to antibiotic regimen in animals challenged with
different bacterial and fungal pathogens (Stahpylococcus aureus,
kiebsiella pneumoniae, Escherchia coli, Candida albicans and others) or
viral pathogens such as herpes and murine viral hepatitis, a reduced
amount of antibiotics or antivirals were needed to cope with the
infection.
Effect of beta glucan on Immune Deficiency:
In certain cases of virally induced immune deficiency, beta glucan
ameliorated the infectious process in these patients possible by
mounting a direct assult against the indigenous viral infection or by
mechanisms referred to above preventing over growth of opportunistic pathogens.
Effect of beta glucan on radiations:
Under experimental conditions, rodents exposed to lethal and
sub-lethal irradiation and administered beta glucan had significantly
larger number of survivors. These observations were attributed to the
fact that beta glucan is a potent free radical scavenger that protects
blood macrophages from free radical attack after radiation exposure
thus ensuring immune function. Additionally administration of beta glucan
enhanced hemopoietic reconstitution and stimulated production of blood
stem cells thus preventing septicemia and resistance to enteric
opportunistic pathogens.
Effect of beta glucan on Chemotherapy:
Chemotherapy may induce immune suppression and result in subsequent
infection with opportunistic infections. Such life threatening
conditions may be averted by administration of beta glucan.
Leukocytopenia is a decrease in the number of white blood cells due to
chemotherapy. Consequently lower dosages of drugs are used which
comprise the curative effect of chemotherapy. However, with beta
glucan, white blood cell deplection may be avoided in experimental
animals. In another experimental model, combination of beta gulcan and
interferon-gamma demonstrated synergistic therapeutic effect.
Similarly superior synergistic potential of beta glucan in combination
with radiation and chemotherapy were reported.
Effect of beta glucan on Wound Healing:
The effectiveness of yeast glucan on acceleration of wound healing was
evaluated in several experimental animal models. In every instance,
animals treated with beta glucan showed more advanced healing. The
histological analysis showed that the acceleration of wound healing
was mediated by early arrival of macrophages to the wound area in the
glucan treated animals.
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