Oral Administration of β-1,3/1,6-Glucan to Dogs Temporally Changes Total and Antigen-Specific IgA and IgM
The effect of oral administration of β-1,3/1,6-glucans from Saccharomyces cerevisiae on humoral immunity in domestic dogs is not known. In this study, 15 beagle dogs were orally given MacroGard tablets, which contain 150 mg of this β-glucan, daily for 4 weeks. At the end of this period, the total serum immunoglobulin A (IgA) level decreased significantly in the group treated with the glucan compared to that in the control group as well as compared to the concentrations before supplementation. In contrast, the total serum IgM level rose significantly, whereas no effect on the IgG level occurred. Similar changes were seen in Bordetella-specific IgA and IgM titers following vaccination during the supplementation period. The IgA concentration also became significantly lower in the saliva and tears of the glucan group than in the placebo group. The effects disappeared 1 week after the cessation of the supplementation. In conclusion, the results showed a temporary change in the isotype profile during glucan supplementation.
Effects of orally administered β – 1,3/1,6 – glucan on vaccination responses and immunological parameters in dogs
The aim of this study was to evaluate immunomodulatory effects of orally administered β-1,3/1,6-glucan on leukocyte functions and vaccination responses in dogs. Thirty puppies were divided into two groups (G and C) of 15 individuals each and vaccinated against rabies and canine parvovirus-2. Dogs from the group G were orally administered 4 mg/kg soluble glucans once daily for 98 days. The phagocytic and metabolic activity of leukocytes and proliferation activity of lymphocytes were evaluated on days 0, 14, 28, 42 and 56. The antibody response to canine parvovirus type 2 and rabies virus were measured weekly. Comparing both groups, we noticed a significant increase in phagocytic activity of leukocytes (p < .001). Protective levels of antibodies against rabies virus, as well as against CPV-2 were reached earlier in the glucan treated group G. Our results suggest positive effects of glucan on some nonspecific immunity parameters, as well as on evaluated vaccination response.
Single Agent Polysaccharopeptide Delays Metastases and Improves Survival in Naturally Occurring Hemangiosarcoma
The 2008 World Health Organization World Cancer Report describes global cancer incidence soaring with many patients living in countries that lack resources for cancer control. Alternative treatment strategies that can reduce the global disease burden at manageable costs must be developed. Polysaccharopeptide (PSP) is the bioactive agent from the mushroom Coriolus versicolor. Studies indicate PSP has in vitro antitumor activities and inhibits the growth of induced tumors in animal models. Clear evidence of clinically relevant benefits of PSP in cancer patients, however, is lacking. The investment of resources required to complete large-scale, randomized controlled trials of PSP in cancer patients is more easily justified if antitumor and survival benefits are documented in a complex animal model of a naturally occurring cancer that parallels human disease. Because of its high metastatic rate and vascular origin, canine hemangiosarcoma is used for investigations in antimetastatic and antiangiogenic therapies. In this double-blind randomized multidose pilot study, high-dose PSP significantly delayed the progression of metastases and afforded the longest survival times reported in canine hemangiosarcoma. These data suggest that, for those cancer patients for whom advanced treatments are not accessible, PSP as a single agent might offer significant improvements in morbidity and mortality.
Immunomodulatory effect of glucan on specific and nonspecific immunity after vaccination in puppies.
The objective of the study was to determine the immunostimulatory effect of β-(1,3/1,6)-D-glucan in puppies. The effect exerted on the efficacy of vaccination, especially against canine parvovirus and rabies infection, was studied. The application of vaccine and glucan leads to significant increases in the nonspecific immunological parameters (phagocytic ability of leukocytes, blastogenic response of lymphocytes, metabolic and chemotactic activity of polymorphonuclear cells). The level of antibodies against canine parvovirus (Ab CPV) and rabies infection reached the most statistically significant values on the 28th day after the application of vaccine and a syrup containing β-(1,3/1,6)-D-glucan (Group GV) as compared to the control group (Group V, puppies receiving only vaccine). Dogs without glucan supplementation did not produce such significant levels of antibodies. We can conclude that glucan has relevant immunostimulatory effects in dogs with altered immunity.
Immunomodulatory activities associated with beta-glucan derived from Saccharomyces cerevisiae.
In this study we investigated the effect of beta-glucan derived from Saccharomyces cerevisiae on fungicidal activity, cytokine production and natural killer activity. Spleen and peritoneal cells from female C57BL/6 mice, previously injected (24 or 48 h) with 20 or 100 microg of glucan by i.p. route, were assayed. In vivo beta-glucan administration primed spleen cells for a higher production of IL-12 and TNF-alpha when S. aureus was used as a stimulus. In addition, beta-glucan increased NK spleen cells activity against YAC target cells. Some immunomodulatory activities not yet described for beta-glucan were observed in this work.
Influence of β-1,3/1,6-D-glucan on non-specific cellular defence mechanisms in lambs
(Wójcik et al.); Medycyna weterynaryjna 63(1):84-86
The aim of the study was to estimate the influence of β-1,3/1,6-D- glucan applied in feed on non-specific cellular immunity in lambs. The study examined twenty six 21-28 day old lambs in two groups: I - control and II - experimental (7 rams and 6 ewes in each group). The animals were kept under identical zoohygienic and nutritional conditions. Lambs from group I were fed a basal control diet and lambs from group II were fed a diet containing β-1,3/1,6-D-glucan, at doses of 80 mg/kg/day. Blood was taken from the control and experimental groups before the lambs were fed a diet containing β-1,3/1,6-D-glucan, and 15, 30 and 60 days after administration of the diet. The respiratory burst activity (RBA) and potential killing activity (PKA) of blood phagocytes and proliferative response of blood lymphocytes (MTT) stimulated by mitogens concanavalin A (ConA) and lipopolisaccharide (LPS) were examined. The results indicated that when β-1,3/1,6-D-glucan was applied to food it statistically significantly increased the blood phagocyte and lymphocyte activity in the lambs until the end of experiment, compared to the control group.
Medicinal importance of fungal beta-(1-->3), (1-->6)-glucans.
Non-cellulosic beta-glucans are now recognized as potent immunological activators, and some are used clinically in China and Japan. These beta-glucans consist of a backbone of glucose residues linked by beta-(1-->3)-glycosidic bonds, often with attached side-chain glucose residues joined by beta-(1-->6) linkages. The frequency of branching varies. The literature suggests beta-glucans are effective in treating diseases like cancer, a range of microbial infections, hypercholesterolaemia, and diabetes. Their mechanisms of action involve them being recognized as non-self molecules, so the immune system is stimulated by their presence. Several receptors have been identified, which include: dectin-1, located on macrophages, which mediates beta-glucan activation of phagocytosis and production of cytokines, a response co-ordinated by the toll-like receptor-2. Activated complement receptors on natural killer cells, neutrophils, and lymphocytes, may also be associated with tumour cytotoxicity. Two other receptors, scavenger and lactosylceramide, bind beta-glucans and mediate a series of signal pathways leading to immunological activation. Structurally different beta-glucans appear to have different affinities toward these receptors and thus generate markedly different host responses. However, the published data are not always easy to interpret as many of the earlier studies used crude beta-glucan preparations with, for the most part, unknown chemical structures. Careful choice of beta-glucan products is essential if their benefits are to be optimized, and a better understanding of how beta-glucans bind to receptors should enable more efficient use of their biological activities.
Ginseng consumption and risk of cancer: A meta-analysis
The findings of currently available studies are not consistent with regard to the association between the risk of cancer and ginseng consumption. Therefore, we aimed to evaluate this association by conducting a meta-analysis of different studies. To systematically evaluate the effect of ginseng consumption on cancer incidence, six databases were searched, including PubMed, Ovid Technologies, Embase, The Cochrane Library, etc.). The findings of this meta-analysis indicated that ginseng consumption is associated with a significantly decreased risk of cancer and that the effect is not organ specific.
The awakened immune system sweeps out tumours
(Tátrai Péter) MTA
The combined immunostimulant treatment elaborated by researchers of Stanford University (California) lets loose the entire tumour-killing potential of the immune system.Awakened from the paralysis forced upon them by the tumour, the immune cells sweep out the tumour and its metastases from the body as if they were eliminating a viral infection. According to its inventor, Ronald Levy this procedure, hitherto tried out only in mice, may theoretically prove suitable for the treatment of all kinds of tumours, and its clinical trials may start already at the end of 2018. In its enjoyable and easily intelligible article, the biologist Péter Tátrai provides a detailed analysis of these results, which were announced at the beginning of the year and created a great stir in the medical profession as well as in the media.