Porcine Brain Enzyme Hydrolysate Enhances Immune Function and Antioxidant Defense via Modulation of Gut Microbiota in a Cyclophosphamide-Induced Immunodeficiency Model.

This study examined how consuming porcine brain enzyme hydrolysate (PBEH) affects the immune function and composition of the gut microbiota in an immunodeficient animal model. Male Wistar rats aged 6 weeks were fed casein (control), 100 mg/kg body weight (BW), red ginseng extract (positive-control), and 6, 13, and 26 mg PBEH per kg BW (PBEH-L, PBEH-M, and PBEH-H, respectively) daily for 4 weeks. At 30 min after consuming assigned compounds, they were orally administered cyclophosphamide (CTX; 5 mg/kg BW), an immunosuppressive agent, to suppress the immune system by inhibiting the proliferation of lymphocytes. The normal-control rats were fed casein and water instead of CTX. Natural killer cell activity and splenocyte proliferation induced by 1 µg/mL lipopolysaccharide were lower in the control group than the normal-control group, and they significantly increased with PBEH consumption, particularly at high doses. The PBEH consumption increased dose-dependently in the Th1/Th2 ratio compared to the control. The lipid peroxide contents were lower in the PBEH group than in the control group. Moreover, PBEH m and PBEH-H consumption mitigated white pulp cell damage, reduced red pulp congestion, and increased spleen mast cells in the histological analysis. Intestinal microbiota composition demonstrated differences between the groups at the genus levels, with Akkermansia being more abundant in the control group than the normal-control group and the PBEH-H group showing a decrease. However, Bifidobacterium decreased in the control group but increased in the PBEH-H group. The ß-diversity revealed distinct microbial communities of PBEH and positive-control groups compared to the control group (p < 0.05). The metagenome predictions revealed that PBEH-H influenced amino acid metabolism, antioxidant defense, insulin sensitivity, and longevity pathways. In conclusion, PBEH-H intake boosted immune responses and reduced lipid peroxides by modulating gut microbiota composition. These findings suggest that PBEH-H has the potential as a dietary supplement for improving immune function and gut health in individuals with immunodeficiency.

Modulating effects of heat-killed and live Limosilactobacillus reuteri PSC102 on the immune response and gut microbiota of cyclophosphamide-treated rats.

In the present study, we investigated the potential immunomodulatory effects of heat-killed (hLR) and live Limosilactobacillus reuteri PSC102 (LR; formerly Lactobacillus reuteri PSC102) in RAW264.7 macrophage cells and Sprague-Dawley rats. RAW264.7 murine macrophage cells were stimulated with hLR and LR for 24 h. Cyclophosphamide (CTX)-induced immunosuppressed Sprague-Dawley rats were orally administered with three doses of hLR (L-Low, M-Medium, and H-High) and LR for 3 weeks. The phagocytic capacity, production of nitric oxide (NO), and expression of cytokines in RAW264.7 cells were measured, and the different parameters of immunity in rats were determined. hLR and LR treatments promoted phagocytic activity and induced the production of NO and the expression of iNOS, TNF-α, IL-1ß, IL-6, and Cox-2 in macrophage cells. In the in vivo experiment, hLR and LR treatments significantly increased the immune organ indices, alleviated the spleen injury, and ameliorated the number of white blood cells, granulocytes, lymphocytes, and mid-range absolute counts in immunosuppressive rats. hLR and LR increased neutrophil migration and phagocytosis, splenocyte proliferation, and T lymphocyte subsets (CD4+, CD8+, CD45RA+, and CD28+). The levels of immune factors (IL-2, IL-4, IL-6, IL-10, IL-12A, TNF-α, and IFN-γ) in the hLR and LR groups were upregulated compared with those in the CTX-treatment group. hLR and LR treatments could also modulate the gut microbiota composition, thereby increasing the relative abundance of Bacteroidetes and Firmicutes but decreasing the level of Proteobacteria. hLR and LR protected against CTX-induced adverse reactions by modulating the immune response and gut microbiota composition. Therefore, they could be used as potential immunomodulatory agents.

Immuno-Enhancing Effects of Galium aparine L. in Cyclophosphamide-Induced Immunosuppressed Animal Models.

This study investigates the immunomodulatory potential of Galium aparine L. (GAE) in immunodeficient animals. In this study, animals were categorized into five groups: the normal group, CYP group (cyclophosphamide intraperitoneal injection), GA5 group (cyclophosphamide + 5 µg GAE), GA50 group (cyclophosphamide + 50 µg GAE), and GA500 group (cyclophosphamide + 500 µg GAE). The CYP group exhibited significantly reduced spleen weights compared to the normal group, while the groups obtaining GAE displayed a dose-dependent increase in spleen weight. Furthermore, the GAE demonstrated dose-dependent enhancement of splenocyte proliferating activity, with significant increases observed in both LPS and ConA-induced assays. NK cell activity significantly increased in the GA50 and GA500 groups compared to the CYP group. Cytokine analysis revealed a significant increase in IL-6, TNF-α, and IFN-γ levels in ConA-induced splenocytes treated with GAE. Gene expression analysis identified 2434 DEG genes in the extract groups. Notable genes, such as Entpd1, Pgf, Thdb, Syt7, Sqor, and Rsc1al, displayed substantial differences in individual gene expression levels, suggesting their potential as target genes for immune enhancement. In conclusion, Galium aparine L. extract exhibits immunomodulatory properties. The observed gene expression changes further support the potential of Galium aparine L. extract as a natural agent for immune augmentation.

Immunostimulatory Activity of Cordyceps militaris Fermented with Pediococcus pentosaceus SC11 Isolated from a Salted Small Octopus in Cyclophosphamide-Induced Immunocompromised Mice and Its Inhibitory Activity against SARS-CoV 3CL Protease.

In this study, we investigated the immune-enhancing and anti-viral effects of germinated Rhynchosia nulubilis (GRC) fermented with Pediococcus pentosaceus SC11 (GRC-SC11) isolated from a salted small octopus. The cordycepin, ß-glucan, and total flavonoid contents increased in GRC after SC11 fermentation. GRC-SC11 inhibits 3CL protease activity in severe acute respiratory syndrome-associated coronavirus (SARS-CoV). GRC-SC11 significantly increased thymus and spleen indices in immunocompromised mice. The rate of splenocyte proliferation was higher in GRC-SC11-treated immunocompromised mice than that in GRC-treated immunocompromised mice in the presence or absence of concanavalin A. In addition, GRC-SC11 increased the phagocytic activity and nitric oxide production in immunocompromised mice. The mRNA expression of interferon-gamma (IFN-γ), interferon-alpha (IFN-α), and interferon-stimulated gene 15 (ISG15) was up-regulated in GRC-SC11 treated RAW 264.7 macrophages, compared to GRC. Our study indicates that GRC-SC11 might be a potential therapeutic agent for immunocompromised patients who are vulnerable to SARS-CoV infection.

Melatonin attenuates diabetes-induced oxidative stress in spleen and suppression of splenocyte proliferation in laboratory mice.

Hyperglycaemic condition induced oxidative stress in diabetic individuals caused oxidative damages of internal organs, including immune organ spleen. We studied the effects of low doses of melatonin (25, 50, and 100 µg/100g. B.wt./day) on histoarchitecture, oxidative stress, and splenocyte proliferation in streptozotocin-induced diabetic mice. Melatonin significantly resisted the increase in blood glucose levels and showed a dose-dependent effect on circulatory melatonin, body weight, and relative spleen weight in diabetic mice. Exogenous melatonin suppressed the diabetes-induced lipid peroxidation and increased the activity of the antioxidant enzymes and antioxidant GSH in the spleen tissue of diabetic mice in a dose-dependent manner. Melatonin improved the reactivity of Nrf-2 and HO-1 in the spleen of diabetic mice. Melatonin treatment normalised the splenic cellularity and increased the splenocyte proliferation in a dose-dependent manner. The present study may suggest the dose-dependent effect of melatonin in attenuation of oxidative stress and suppression of splenocyte proliferation in diabetic mice.

Toxic mechanisms of cigarette smoke and heat-not-burn tobacco vapor inhalation on rheumatoid arthritis.

Tobacco combustion exposure worsens rheumatoid arthritis (RA). Non-combustible tobacco devices, as heat-not-burn tobacco (HNBT), are emerging as harm reduction to smokers by releasing nicotine and lower combustible tobacco products. Nevertheless, HNBT toxicity remains unclear. Hence, here we investigated the impacts of the tobacco combustible product (cigarette smoke; CS) or HNBT vapor exposures on antigen-induced arthritis (AIA) in C57BL/6 mice. Animals were exposed to airflow, HNBT vapor, or CS during 1 h/twice a day, under the Health Canada Intense (HCI) smoking regime, between days 14 to 20 after the first immunization. At day 21, 16 h after the last exposures, mice were i.a. challenged and the AIA effects were evaluated 24 h later. CS- or HNBT-exposed mice presented equivalent blood nicotine levels. CS exposure worsened articular symptoms, pulmonary inflammation, and expression of lung metallothioneins. Nevertheless, CS or HNBT exposures reduced lymphoid organs' cellularity, splenocyte proliferation and IL-2 secretion. Additional in vitro CS or HNBT exposures confirmed the harmful effects on splenocytes, which were partially mediated by the activation of nicotine/α7nAchR pathway. Associated, data demonstrate the toxic mechanisms of CS or HNBT inhalation at HCI regime on RA, and highlight that further investigations are fundamental to assure the toxicity of emerging tobacco products on the immune system during specific challenges.

Immunosuppressive activity of daphnetin on the humoral immune responses in ovalbumin-sensitized BALB/c mice.

INTRODUCTION: Most of the immunosuppressive drugs are used for the treatment of autoimmune disease, allergic diseases, and transplant rejection, but toxicity is the major obstacle for the potent drugs in the wide use of these immunosuppressive drugs. Daphnetin, a Chinese herbal product, has been reported that daphnetin possesses antimicrobial, anticoagulation, antimalarial, anticancer, and antioxidant activity. In a previous study, we found that daphnetin exhibited a potential immunosuppressive effect on LPS-induced B lymphocyte cells in vitro, therefore, in this research, we investigated the immunosuppressive effects of daphnetin in BALB/c mice use OVA as a prototype antigen. METHODS: Sixty BALB/c mice were divided into six groups. The emulsion (100 µL containing 100 µg OVA) was injected subcutaneously with OVA + CFA into the shaved backs of the BALB/c mice on day 1, and a boosting injection was administered in OVA + IFA 2 weeks later. Beginning on the day of immunization, the immunized mice were administered intraperitoneally with daphnetin at a dose of 5, 10, and 20 mg/kg in saline solution for 28 consecutive days. We measured the effect of daphnetin on OVA-specific antibody, cytokine production, and Splenocyte proliferation in vivo. RESULTS: The results revealed that daphnetin significantly suppressed serum immunoglobulin G levels (IgG), and the OVA-specific IgG subclasses IgG1 and IgG2b, daphnetin was also significantly decreased the Th1 and Th2 cytokine productions, inhibited the splenocytes proliferation rate in vivo. CONCLUSIONS: It proved that daphnetin could suppress humoral response activity on OVA-sensitized mice, suggesting a potential role on daphnetin as a new immunosuppressive drug.

4-Methylpseudoproline analogues of cyclolinopeptide A: Synthesis, structural analysis and evaluation of their suppressive effects in selected immunological assays.

The synthesis of new analogues of cyclolinopeptide A (CLA) and their linear precursors modified with (R)- and (S)-4-methylpseudoproline in the Pro3-Pro4 fragment are presented. The peptides were tested in comparison with cyclosporine A (CsA) in concanavalin A (Con A) and pokeweed mitogen (PWM)-induced mouse splenocyte proliferation and in secondary humoral immune response in vitro to sheep erythrocytes (SRBC). Their effects on expression of selected signaling molecules in the Jurkat T cell line were also determined. In addition, the structural features of the peptides, applying nuclear magnetic resonance and circular dichroism, were analyzed. The results showed that only peptides 7 and 8 modified with (R)-4-methylpseudoproline residue (c(Leu1-Val2-(R)-(αMe)Ser(ΨPro)3-Pro4-Phe5-Phe6-Leu7-Ile8-Ile9) and c(Leu1-Val2-Pro3-(R)-(αMe)Ser(ΨPro)4-Phe5-Phe6-Leu7-Ile8-Ile9), respectively) strongly suppressed mitogen-induced splenocyte proliferation and the humoral immune response, with peptide 8 being more potent. Likewise, peptide 8 more strongly elevated expression of Fas, a proapoptotic signaling molecule in Jurkat cells. We postulate that the increased biological activity of peptide 8, compared to the parent molecule and other studied peptides, resulted from its more flexible structure, found on the basis of both CD and NMR studies. CD and NMR spectra showed that replacement of Pro3 by (R)-(αMe)Ser(¬Pro) caused much greater conformational changes than the same replacement of the Pro4 residue. Such a modification could lead to increased conformational freedom of peptide 8, resulting in a greater ability to adopt a more compact structure, better suited to its putative receptor. In conclusion, peptide 8 is a potent immune suppressor which may find application in controlling immune disorders.

Effect of lead exposure and nutritional iron-deficiency on immune response: A vaccine challenge study in rats.

The prevalence of iron (Fe) deficiency and subclinical lead (Pb) toxicity is high in developing countries like India, and information on their potential additive effects on immune responses is scant. The current study assessed immune parameters in dual Pb-exposed\Fe-deficient weanling SD rats. Rats were fed a control (CD) or Fe-deficient (ID) diet for 4 weeks and then evaluated for hemoglobin (Hb) and serum Fe status. Then, half the rats in each group began to receive daily oral Pb exposure (25 mg/4 ml/kg BW; gavage) or vehicle for a further 4 weeks (while maintained on original respective diets). After the 4-weeks of dosing, rats were assessed for Hb and serum Fe, and for blood lead level (BLL) and δ-aminolevulinic acid dehydratase (ALAD) activity. At this point, half the rats in each group (now n = 8) were then vaccinated with tetanus toxoid (TT), and then two boosters at 2-week intervals. All the time, rats stayed on their original respective diets along with exposure to Pb on alternate days. At 2 weeks after the final booster, rats were euthanized and blood collected to assess total/specific IgG and IgM levels; mucosal (intestinal) IgA levels were also determined. Spleens were taken to assess CD4+ and CD8+ cell levels and for ex vivo measures of splenocyte proliferation/TH1 and TH2 cytokine formation. The results indicated significant lowering of Hb and serum Fe levels in ID rats and increased blood Pb and decreased ALAD activity in all Pb-exposed rats. Fe-deficiency alone induced significant increases in ALAD activity, but only in an absence of Pb. While there was no impact of any regimen on total or TT-specific IgG, significant decreases in mucosal IgA and TT-specific IgM were seen in ID-fed Pb-exposed rats. CD4+ cell levels were not impacted by treatment; CD8+ levels were increased in all ID/Pb-exposed rats. Ex-vivo splenocyte proliferation was significantly higher among vaccinated rats, as well as ID-fed Pb-exposed unvaccinated rats. Cytokine formation in all cases was highly variable. The results suggest that Fe deficiency compromised cell-mediated, mucosal, and/or humoral immune response-related endpoints and that Pb exposure during the deficiency further impacted these outcomes.

Splenocyte-mediated immune enhancing activity of Sargassum horneri extracts / 한국영양학회지

PURPOSE: This study examined the immunological activity and optimized the mixture conditions of Sargassum horneri (S. horneri) extracts in vitro and in vivo models.METHODS: S. horneri was extracted using three different methods: hot water extraction (HWE), 50% ethanol extraction (EE), and supercritical fluid extraction (SFE). Splenocyte proliferation and cytokine production (Interleukin-2 and Interferon-γ) were measured using a WST-1 assay and enzyme-linked immunosorbent assay, respectively. The levels of nitric oxide and T cell activation production were measured using a Griess assay and flow cytometry, respectively. The natural killer (NK) cell activity was determined using an EZ-LDH kit.RESULTS: Among the three different types of extracts, HWE showed the highest levels of splenocyte proliferation and cytokine production in vitro. In the animal model, three different types of extracts were administrated for 14 days (once/day) at 50 and 100 mg/kg body weight. HWE and SFE showed a high level of splenocyte proliferation and cytokine production in the with and without mitogen-treated groups, whereas EE administration did not induce the splenocyte activation. When RAW264.7 macrophage cells were treated with different mixtures (HWE with 5, 10, 15, 20% of SFE) to determine the optimal mixture ratio of HWE and SFE, the levels of nitric oxide and cytokine production increased strongly in the HWE with 5% and 10% of SFE containing group. In the animal model, HWE with 5% and 10% of SFE mixture administration increased the levels of splenocyte proliferation, cytokine production, and activated CD4⁺ cell population significantly, with the highest level observed in the HWE with 5% of SFE group. Moreover, the NK cell activity was increased significantly in the HWE with 5% of SFE mixture-treated group compared to the control group.CONCLUSION: The optimal mixture condition of S. horneri with immune-enhancing activity is the HWE with 5% of SFE mixture. These results confirmed that the extracts of S. horneri and its mixtures are potential candidate materials for immune enhancement.

Immunomodulatory activity of non starch polysaccharides isolated from green gram (Vigna radiata).

Green gram, rich in dietary fiber is known to enhance the function of immune system. However information pertaining to the immunomodulatory potential of its non starch polysaccharides (NSPs) is scanty. Hence, five different NSPs were extracted successively using water (WSP), hot water (55 o C, HWSP), EDTA (0.5%, Pectins) and alkali (10%, Hemicellulose A and B) which varied in their arabinose to galactose ratio, sugar, protein, uronic acid contents, molecular weight distribution and immunomodulatory activity. Hemicellulose B was relatively rich in carbohydrate content (~95%) and also possessed potent immunomodulatory activity among the various NSPs. Hemicellulose B was further fractionated on DEAE-cellulose column into six different fractions by eluting step-wise with water, ammonium carbonate (0.1, 0.2, 0.3 M AC) and sodium hydroxide (0.1 and 0.2 M NaOH). 0.1 M AC eluted fraction was found to be the major one amounting to ~ 50% yield and showed relatively significant (p < 0.001) activity towards splenocyte proliferation and macrophage activation as compared with rest of the DEAE eluted fractions.

Immunomodulatory activity of Lactobacillus plantarum KLDS1.0318 in cyclophosphamide-treated mice.

BACKGROUND: Probiotics in fermented foods have attracted considerable attention lately as treatment options for immune diseases, the incidence of which has been increasing throughout the world. OBJECTIVE: The objective of the present study was to investigate the immunomodulatory activity of Lactobacillus plantarum (L. plantarum) KLDS1.0318 in cyclophosphamide-treated mice. DESIGN: To investigate the immune-enhancing effects of L. plantarum KLDS1.0318, we used a immunosuppressive model. Ninety female six-week-old BALB/c mice were randomly divided into six groups: normal control (NC) group, model control (MC) group, immunosuppression plus L. plantarum KLDS1.0318 groups with three different doses (KLDS1.0318-L, KLDS1.0318-M, and KLDS1.0318-H), and plus levamisole hydrochloride as positive control (PC) group. RESULTS AND DISCUSSIONS: Results showed that the thymus and spleen indexes of the four treatment groups were significantly higher than those of the MC group (2.01±0.16) ( p < 0.05). The capacity of lymphocyte proliferation, the activity of natural killer (NK) cell and macrophages phagocytosis were significantly increased ( p < 0.05) in four treatment groups as compared with the MC group (0.327±0.022, 62.29±0.8, 0.087±0.008, respectively). The levels of relative immune factors (IL-2, IL-6, and IFN-γ) showed similar patterns ( p < 0.05). CONCLUSIONS: This study suggested that orally administered L.plantarum KLDS1.0318 may effectively accelerate the recovery of immunosuppressive mice caused by cyclophosphamide (CTX). The immunomodulatory activity of the srtain recommended that L. plantarum KLDS1.0318 could be used as a powerful medicinal treatment against immunosuppression.

Effect of Cyclophosphamide Treatment on Central and Effector Memory T Cells in Mice.

Immunological memory is a key feature of adaptive immunity. It provides the organism with long-lived and robust protection against infection. The important question is whether cyclophosphamide (CP), as immunosuppressive agent used in cancer therapy and in some autoimmune diseases, may act on the memory T-cell population. We investigated the effect of CP on the percentage of central memory T cells (TCM) and effector memory T cells (TEM) in the mouse model of CP-induced immunosuppression (8-10-week-old male C57BL/6 mice CP treated for 7 days at the daily dose of 50 µg/g body weight [bw], manifested the best immunosuppression status, as compared to lower doses of CP: 10 or 20 µg/g bw). The CP induced a significant decrease in the percentage of CD8+ (TCM), compared to nonimmunosuppressed mice. This effect was not observed in the case of CD4+ TCM population. The percentage of gated TEM with CD4 and CD8 phenotype was significantly decreased in CP-treated mice, as compared to the control ones. Taken together, the above data indicate that CP-induced immunosuppression in mice leads to a reduction in the abundance of central memory cells possessing preferentially CD8+ phenotype as well as to a reduction in the percentage of effector memory cells (splenocytes both CD4+ and CD8+), compared to the cells from nonimmunosuppressed mice. These findings in mice described in this article may contribute to the understanding of the complexity of the immunological responses in humans and extend research on the impact of the CP model of immunosuppression in mice and memory T-cell populations.

Anti-inflammatory effect of dietary pork extract on proliferation and cytokine secretion using mouse primary splenocytes.

The anti-inflammatory effects of boiled pork meat (BPM) and hot water extracts of pork meat (WPM) on splenocyte proliferation and T cell cytokine regulation in BALB/c mice were evaluated. The proliferation of splenocytes in high concentration WPM groups was significantly higher than the control stimulated by LPS and Con A. In the white blood cells, WPM groups had significantly higher counts of lymphocytes and lower counts of neutrophils than the control (p<0.05). The Th1 (IFN-γ, TNF-α, IL-2) and Th2 (IL-4, IL-5, IL-10) cytokine levels in high-concentration WPM groups were higher than those in the control. In addition, TNF-α/IL-10 and IL-2/IL-4 secretions of splenocytes in the high concentration WPM group with LPS or Con A treatment was significantly lower than the control (p<0.05). Therefore, this study suggested that high concentration of WPM had anti-inflammatory effects on the primary splenocyte, which indicating that water extracts of pork meat can enhance the immune system of mice.

Lactobacillus rhamnosus GG supplementation during critical windows of gestation influences immune phenotype in Swiss albino mice offspring.

Probiotic supplementation during critical windows of gestation might have a significant influence on the infant's immune phenotype. Swiss albino mice (F0 generation) aged 31 days were supplemented orally with probiotic Lactobacillus rhamnosus GG (LGG); and the supplementation was continued throughout mating, gestation and lactation. The pups (F1 generation) born to them were separated post weaning and received either the same probiotic supplementation as their mothers or were denied supplementation postnatally. Neutrophil phagocytic ability, splenocyte proliferation, immunoglobulins and cytokines were determined in both F0 and F1 pups. In addition, antibody response against hepatitis-B surface antigen (HBsAg) was determined in F1 pups. Probiotic supplementation had no effect on the neutrophil phagocytic ability and splenocyte proliferation index. The serum immunoglobulin G (IgG) and secretory IgA (s-IgA) among the probiotic supplemented group of F0 generation were significantly (P<0.05) higher compared to the controls. Similarly, the mean concentration of interleukin (IL)-10, IL-17 and interferon gamma (IFN-γ) among F0 probiotic group were significantly higher (P<0.05) compared to the control. Prenatal and postnatal probiotic supplementation in F1 pups led to similar results as F0 dams. Prenatal probiotic supplementation in F1 pups led to significantly (P<0.05) higher serum IgG (55.15 ± 1.35 ng/ml) and intestinal s-IgA (77.9 ± 2.86 ng/mg protein) concentration when compared to the control. Similarly, IFN-γ concentration increased (P<0.05) with prenatal probiotic supplementation compared to the control. However, IL-10 and IL-17 concentrations of prenatal probiotic supplemented F1 pups were comparable to the control. As for the antibody response to HBsAg, prenatal probiotic supplementation led to enhanced HBsAg antibody response (471.4 ± 3.97 U/ml) compared to the control. LGG affected the immune regulation and immune responses favourably in mothers and offspring. In addition, some of the beneficial effects of prenatal LGG supplementation extended into postnatal life of the offspring, thus suggesting possible immunoprogramming effect of LGG.

Polysaccharides from Cymbopogon citratus with antitumor and immunomodulatory activity.

UNLABELLED: Abstract Context: Most of the present studies on the antitumor efficiency of Cymbopogon citratus (DC.) Stapf (Gramineae) are limited to its low-mass compounds, and little information about the antitumor activity of polysaccharides from this plant is available. OBJECTIVES: This study focused on the potential antitumor and immunomodulatory activities of polysaccharides (CCPS) from C. citratus. MATERIALS AND METHODS: CCPS was isolated using the water extraction-ethanol precipitation method. The sarcoma 180 (S180) cells-inoculated mice were intraperitoneally administrated with CCPS (30-200 mg/kg/d) for seven consecutive days. The effects of CCPS on tumor growth, thymus and spleen weights, splenocyte proliferation, and cytokine secretion in the tumor-bearing mice were measured. The cytotoxicity of CCPS (50-800 µg/mL) towards S180 cells was also studied. RESULTS: CCPS significantly inhibited the growth of the transplanted S180 tumors, with the inhibition rates ranging from 14.8 to 37.8%. Simultaneously, CCPS dose-dependently improved the immunity of the tumor-bearing mice. With the highest dose of 200 mg/kg/d, the thymus and spleen indices were increased by 21.9 and 91.9%, respectively; ConA- and LSP-induced splenocyte proliferations were increased by 32.7 and 35.3%, respectively. The secretions of interleukin 2 (IL-2), interleukin 6 (IL-6), interleukin 2 (IL-12), and tumor necrosis factor-α (TNF-α) were increased by 103.2, 40.2, 23.6, and 26.3%, respectively. Nevertheless, almost no toxicity of CCPS towards S180 cells was observed, with the maximal inhibition rate less than 15% at the CCPS concentration of 800 µg/mL. CONCLUSION: CCPS exhibited antitumor activity in vivo, and this activity might be achieved by immunoenhancement rather than direct cytotoxicity.

Endocrine and immune system interactions during pregnancy.

Pregnancy is known to induce a transient depression of maternal cell-mediated immunity, to prevent rejection of the fetus, while at the same time it keeps adequate maternal host defense mechanisms to fight infection. Presently, the aim of this paper was to investigate a possible endocrine and immunologic alteration observed during a successful pregnancy. This study consistently showed that plasma corticosterone levels were significantly higher (P<0.0001) in pregnant Wistar rats than in virgin female. An increased number of peritoneal macrophages was also detected in pregnant females when compared to non-pregnant ones. Macrophages play an important role in the production of bioactive proteins and lipids such as nitric oxide. Then, in support of the latter, the present study showed increased levels of endogenous NO in pregnant rats when compared to non-pregnant ones, thereby mediating the vasodilatation process of normal gestation. Furthermore, our FACS analysis clearly indicated the correlation between reduced CD161 expression on NK cells (P<0.0001) in pregnant rats when compared to virgin females. It was found that pregnancy appears to be associated with depressed cell immunity, as evidenced by a significant inhibition of lymphocyte proliferation. Understanding the immunological paradox of maternal tolerance, as well as the hormonal modulation of the immune environment during pregnancy is essential for future studies to investigate the potential for these processes to be modulated by diet or effective therapeutics during pregnancy.

Mycoplasma hyorhinis induces proinflammatory responses in mice lymphocytes.

Mycoplasmas are frequent contaminants of cultured cells, leading to alterations in cellular gene expression, protein synthesis, signal transduction, and metabolic pathways. Mycoplasma hyorhinis, the major contaminant of tissue cultures, has been implicated in a variety of diseases in swine. Most human and animal mycoplasmas remain attached to the surface of epithelial cells. Nonetheless, we have recently shown that M. hyorhinis is able to invade nonphagocytic melanoma cells. In the present study, we show by confocal laser scanning microscopy, that by exposing mice splenocytes to intact M. hyorhinis, intracellular mycoplasmas were detected. Mycoplasmal components were not detected within splenocytes after exposure to heat inactivated M. hyorhinis or to a purified M. hyorhinis lipoprotein (LPP) fraction. However, incubation of the splenocytes with intact M. hyorhinis cells, heat inactivated cells or M. hyorhinis LPP fraction induced accelerated cell proliferation and the secretion of interferon gamma and interleukin 17. Thus, M. hyorhinis and its LPPs can be added to the list of infectious agents causing direct stimulation of proinflammatory responses by mammalian lymphocytes.

Immune stimulatory activity of BRP-4, an acidic polysaccharide from an edible plant, Basella rubra L.

OBJECTIVE: To evaluated the immunomodulatory effect of BRP-4, an acidic polysaccharide from Basella rubra (B. rubra) L on the macrophage activity. METHODS: Phagocytic activity was determined by the ingestion of Latex Beads-Rabbit IgG-FITC using the fluorescent microscopy and flow cytometry analysis and nitric oxide production was measured using Griess reaction assay. RESULTS: An enhanced production of NO was observed at 10 and 100 µg/mL of BRP-4. The phagocytic activity of macrophage was enhanced in BRP-4 treated RAW264.7 cells. BRP-4 combined with concanavalin A (Con A) provided obvious promotion and strengthening of the proliferation of the splenocytes. CONCLUSIONS: BRP-4, polysaccharide isolated from B. rubra, is suggested to activate macrophage function and stimulate splenocyte proliferation. The strong immunomodulatory activity of BRP-4 confirmed its good potential as an immunotherapeutic adjuvant.

Immunopotentiating properties of extracellular polysaccharide from Trametes hirsuta strain VKESR.

The effectiveness of extracellular polysaccharides isolated from Trametes hirsuta strain VKESR was evaluated for their immunostimulating properties by in vitro lymphocyte proliferation, phagocytic assay, NK cell activity and cytokine quantification. The splenocyte proliferation assay showed that the extracellular glucans found to have good stimulation index and enhances the NK cell mediated tumor killing. It promotes phagocytosis in treated macrophages in a dose dependent manner. Furthermore, the polysaccharides exhibit significant stimulatory effect on cytokines IL-2 and IFN-γ whereas the polysaccharide has moderate stimulatory effect pro-inflammatory cytokine TNF-α. These immunostimulating properties help in combating various diseases and could be a promising beginning for further research to study the role of extracellular polysaccharide on the host immune systems.