Immunostimulatory Effects of β-glucan Purified from Paenibacillus polymyxa JB115 on Mouse Splenocytes

Anti-inflammatory and anti-apoptotic potential of beta-glucan on chemotherapy-induced nephrotoxicity in rats

Background/Aim: Cyclophosphamide (CP) is an anti-cancer agent that mediates nephrotoxicity. Beta (β)-glucan has restorative effects on kidney toxicities through its antioxidant potential; however, the effects of β-glucan on CP-induced renal injury remain unknown. In an experimental nephrotoxicity model using rats, we sought to examine the potential protective action of β-glucan on kidney histomorphology, apoptosis, and TNF-α expression. Methods: Male albino Wistar rats were divided equally into four groups: control, CP, β-glucan, and CP+β-glucan. The kidney tissues of the rats were examined for TNF-α and caspase-3 immunostaining to evaluate inflammation and apoptosis, respectively. Hematoxylin and eosin (H&E) and periodic acid–Schiff (PAS) staining were used for histopathological analyses. Results: The CP group showed severe histopathological damage in the renal tissues of rats. In the renal tissue of the CP group, immunoreactivities for TNF-α (1.25 [0.079] and caspase-3 (1.506 [0.143] were also higher than the control group (0.117 [0.006] and 0.116 [0.002], respectively; P<0.001). In the CP+β-glucan group, the histopathological changes significantly improved. Conclusion: Beta-glucan has therapeutic potential against CP-induced nephrotoxicity in rat kidney.

Dynamic Frequency of Blood CD4+CD25+ Regulatory T Cells in Rats with Collagen-induced Arthritis

CD4+CD25+ regulatory T cells (CD4+CD25+ Tregs) have been shown to play a regulatory or suppressive role in the immune response and are possibly relevant to the pathogenesis of autoimmune diseases. In the present study, we attempted to investigate the frequency of CD4+CD25+ Tregs in peripheral blood (PB) of collagen-induced arthritis (CIA) rats during the development of arthritis, to determine whether their frequency is involved in the immunoregulation of this disease. The results showed that normal rats had similar frequencies of CD4+CD25+ Tregs in PB during the experiment time, expressed as a percentage of CD4+CD25+Foxp3+ T cells among the CD4+ T lymphocyte population. In contrast, the frequency of CD4+CD25+Foxp3+ T cells in CIA rats was found to change during the development of arthritis. In CIA rats, there is a significant negative correlation between the frequency of CD4+CD25+Foxp3+ T cells and paw swelling (r=-0.786, p< 0.01). The relationship between the frequency of CD4+CD25+Foxp3+ T and immune activation was not found in normal rats. During the time course, the frequency of CD4+CD25+Foxp3+ T was lower in CIA rats than in normal ones. The data suggest that the frequency of PB CD4+CD25+ Tregs may be a promising marker for arthritis activity.

Evaluation of adjuvant effects of fucoidan for improving vaccine efficacy

Fucoidan is a sulfated polysaccharide derived from brown seaweed, including Fucus vesiculosus. This compound is known to have immunostimulatory effects on various types of immune cells including macrophages and dendritic cells. A recent study described the application of fucoidan as a vaccine adjuvant. Vaccination is regarded as the most efficient prophylactic method for preventing harmful or epidemic diseases. To increase vaccine efficacy, effective adjuvants are needed. In the present study, we determined whether fucoidan can function as an adjuvant using vaccine antigens. Flow cytometric analysis revealed that fucoidan increases the expression of the activation markers major histocompatibility complex class II, cluster of differentiation (CD)25, and CD69 in spleen cells. In combination with Bordetella bronchiseptica antigen, fucoidan increased the viability and tumor necrosis factor-α production of spleen cells. Furthermore, fucoidan increased the in vivo production of antigen-specific antibodies in mice inoculated with Mycoplasma hyopneumoniae antigen. Overall, this study has provided valuable information about the use of fucoidan as a vaccine adjuvant.

The effect of Biolex-MB40 on the phagocytic activity and oxidative metabolism of peripheral blood granulocytes and monocytes in lambs

The objective of this study was to determine the effect of Biolex-MB40 on the phagocytic activity and oxidative metabolism of peripheral blood granulocytes and monocytes in lambs. The experimental material comprised 32 lambs aged 30 +/- 3 days, divided into two equal groups: control and experimental. Experimental group animals were fed a diet supplemented with the Biolex-MB40 (Saccharomyces cerevisiae) in the amount of 3 g/kg of the concentrate. At the beginning of the experiment (day 0) and on experimental days 15, 30 and 60, blood was sampled from the jugular vein to determine and compare the phagocytic activity (PHAGOTEST) and oxidative metabolism (BURSTTEST) of peripheral blood granulocytes and monocytes by flow cytometry. Based on the results of an analysis of granulocyte and monocyte phagocytic activity, statistically higher levels of phagocytic activity were observed in the group of lambs administered Biolex-MB40 than in the control animals, expressed in terms of the percentage of phagocytic cells as well as mean fluorescence intensity. Biolex-MB40 also had a positive effect on the oxidative metabolism of both granulocytes and monocytes after stimulation with Escherichia coli bacteria and with PMA (4-phorbol-12-beta-myristate-13-acetate), expressed in terms of the percentage of oxidative metabolism as well as mean fluorescence intensity.