Caffeic acid and quercetin exert caspases-independent apoptotic effects on Leishmania major promastigotes, and reactivate the death of infected phagocytes derived from BALB/c mice

Objective: To investigate the leishmanicidal effects of two antioxidants, caffeic acid and quercetin on Leishmania major(L.major) promastigotes in vitro, and their immunomodulatory effects on infected phagocytes derived from susceptible BALB/c mice.Methods: Caffeic acid and quercetin-induced cell death was examined by Pi-Hoechst double staining of L.major promastigotes and MTT assay, in the presence or absence of protease inhibitors in vitro.Caffeic acid or quercetin were administered subcutaneously to BALB/c mice infected with L.major promastigotes through a dorsal air pouch.Nitric oxide and superoxide anion production by phagocytes infiltrating the air pouch and the expression of inducible nitric oxide synthase(i NOS), tumor necrosis factor alpha(TNF-a) and nuclear factor kappa B in the air pouch membrane were therefore evaluated using appropriate methods.Results: Caffeic acid and quercetin displayed a dose-dependent cytotoxic effect against L.major promastigotes, and induced cell death via caspases-independent pathways.In vivo, L.major promastigotes inoculation into air pouch cavity of BALB/c mice leads to a sequential influx of neutrophils(hours), followed by macrophages(days).Results showed that L.major delayed apoptosis of infected neutrophils and macrophages by the cleavage of the nuclear factor kappa B p65^(RelA) subunit, and persisted by inhibiting TNF-a and i NOS expression and reactive oxygen species generation.Caffeic acid or quercetin restored reactive oxygen species production and TNF-a-induced i NOS activity, and abrogate apoptosis delay of infected phagocytes.Conclusions: The leishmanicidal effect of caffeic acid and quercetin on promastigotes and amastigotes, as well as reactivation of infected phagocytes apoptosis, suggested a potential therapeutic role against cutaneous leishmaniasis.

Functional Activity of Circulating Phagocytes as Potential Pretreatment Marker of Tumor Drug Resistance

The aim of this work was a study of the functional activity of neutrophils and peripheral blood monocytes in rats with the transplanted Walker carcinosarcoma as potential predictors of the sensitivity of this tumor to doxorubicin treatment. This study provides an evidence that such indices of the functional activity of circulating phagocytes of the tumor-bearing rats as the quantity and the phagocytosis intensity of monocytes, as well as the intensity of ROS production by monocytes and neutrophils, may reflect the degree of sensitivity of the tumor to doxorubicin. So it was shown that the growth of the resistant tumor caused a significant increase of the number of circulating phagocytic cells and the intensity of phagocytosis by more than 100% (p < 0.001) compared with the corresponding indices of intact rats and rats with the parental variant of the tumor. The ability of blood mono-cytes and neutrophils of rats with a resistant tumor to produce ROS was also significantly different from that in intact rats and animals with the parental carcinosarcoma variant. The predictive value of these indices is especially important in the dynamic monitoring of the development of tumor drug resistance during long-term cancer chemotherapy. Considering the standard 2 - 3 week interval between the courses of cancer therapy and the short lifetime of circulating phagocytes, an assessment of the indices of their functional activity before each subsequent course can be considered as a pretreatment assessment. Meanwhile, further studies are needed to determine the spectrum of malignant neoplasms for which the degree of tumor drug resistance correlates with the functional activity of circulating phagocytes.

Superoxide Anion Release by Human Blood Phagocytes Can Increase the Microbicidal Activity Induced by a New Microemulsioned System Containing Cotton Oil

The study aimed to develop and characterize a microemulsified system based on cotton oil and verify its effect on superoxide release anion and microbicidal activity by human peripheral blood cells. Microemulsions were formulated using distilled water, degummed cotton oil, Span 80 (SP), Tween 80 (TW), and 1-butanol (BT). The pseudo-ternary diagram delimited ME regions, and the points were pre-selected. The physical-chemical and rheological characterization of the microemulsions was carried out. The ME activity on the interactions between leukocytes and bacteria was analyzed by superoxide release, phagocytosis, and microbicidal activity. The developed formulation was classified as Oil/Water, with an average pH of 5.76, and the viscosity showed resistance to temperature changes. The rheological model of the Power Law classified the microemulsion as a non-Newtonian fluid with pseudoplastic characteristics. The cell viability of cotton oil microemulsion was greater than 90%. There was an increase in the superoxide release by MN phagocytes when treated with cotton oil microemulsion. The cotton oil microemulsion increased phagocytosis and microbicidal activity. The present study suggests that cotton oil is an alternative biomaterial for therapeutic applications, especially in treating infections.

Antimicrobial roles of phagocytosis in teleost fish:Phagocytic B cells vs professional phagocytes

The defense system of teleost fish organized on innate and adaptive immunity protects them against a wide variety of pathogenic microorganisms in the aquatic environment.Phagocytosis is one of the most effective defense strategies against microbial challenge mainly performed by classical‘professional’phagocytes(including monocytes,macrophages and granulocytes).They contain,kill and process the internalized pathogens for antigen presentation by providing antigenic ligands to initiate activation and clonal expansion of T and B cells,which bridge the innate and adaptive immunity.The discovery of phagocytic B cells in teleost fish has broken the paradigm that primary vertebrate B cells are lack of phagocytosis of particulates,as well as led to the investigation of phagocytic activity of mammalian B-1 B cells.The active phagocytic,microbicidal capabilities and antigen presentation in teleost phagocytic B cell have demonstrated to be similar as professional phagocytes,providing a potential impact on development of new vaccination strategies to prevent and control infectious diseases.In this review,we aim to address current progress on the antimicrobial role of phagocytic B cells in teleost fish by comparing it with other professional phagocytes and mammalian B-1 B cells,and provide the application prospect of phagocytic B cells in developing vaccines as well as the prevention of fish diseases.

Cytotoxic response of phagocytes in patients newly infected with pulmonary Mycobacterium tuberculosis determined using plasma tumor necrosis factor-alpha,malondialdehyde,and superoxide dismutase:an observational study

Objective: PulmonaryMycobacterium tuberculosis infection can trigger cellular and humoral innate immune responses, which may cause death of the pathogen and or host cells/tissue. We aimed to determine the cytotoxic response of phagocytes in patients with pulmonaryMycobacterium tuberculosis infection based on plasma tumor necrosis factor-alpha (TNF-α), malondialdehyde (MDA), and superoxide dismutase (SOD) levels.Methods: In this observational study, patients newly infected with pulmonaryMycobacterium tuberculosis (n=31;age 37-62 years) and age-matched uninfected volunteers (n=50) were recruited as test and control volunteers, respectively in Owo, Nigeria. The study protocol was reviewed and approved by the Research and Ethics Committee of the Department of Medical Laboratory Science, Achievers University, Owo, Nigeria (AUO/MLS/VII/2009/212). Anti-hepatitis C virus, human immunodeficiency virus antigen/antibody, hepatitis B virus surface antigen, and plasma TNF-α were determined by enzyme-linked immunosorbent assay, SOD, and MDA were determined by colorimetry,Plasmodium by Giemsa thick blood film staining, and acid-fast bacilli in sputum were detected by Ziehl-Neelsen staining.Results: All participants had normal blood glucose levels and tested negative for human immunodeficiency virus antigen/antibody, anti-hepatitis C virus, hepatitis B virus surface antigen, andPlasmodium spp., and had no medical history of cancer. Infected patients had significantly higher plasma MDA and TNF-α levels and significantly lower SOD levels compared with control subjects (allP<0.05).Conclusion: Mycobacterium tuberculosis infection elicited a cytotoxic response by phagocytes, evidenced by significant increases in MDA and TNF-α and a significant decrease in SOD levels.

Probiotic metabolites from Bacillus coagulans GanedenBC30^(TM) support maturation of antigen-presenting cells in vitro

AIM:To study the effects of probiotic metabolites on maturation stage of antigen-presenting immune cells.METHODS:Ganeden Bacillus coagulans 30(GBC30) bacterial cultures in log phase were used to isolate the secreted metabolite(MET) fraction.A second fraction was made to generate a crude cell-wall-enriched fraction,by centrifugation and lysis,followed by washing.A preparation of MET was subjected to size exclusion centrifugation,generating three fractions:< 3 kDa,3-30 kDa,and 30-200 kDa and activities were tested in comparison to crude MET and cell wall in primary cultures of human peripheral blood mononuclear cell(PBMC) as a source of antigen-presenting mononuclear phagocytes.The maturation status of mononuclear phagocytes was evaluated by staining with monoclonal antibodies towards CD14,CD16,CD80 and CD86 and analyzed by flow cytometry.RESULTS:Treatment of PBMC with MET supported maturation of mononuclear phagocytes toward both macrophage and dendritic cell phenotypes.The biological activity unique to the metabolites included a reduction of CD14+ CD16+ pro-inflammatory cells,and this property was associated with the high molecular weight metabolite fraction.Changes were also seen for the dendritic cell maturation markers CD80 and CD86.On CD14dim cells,an increase in both CD80 and CD86 expression was seen,in contrast to a selective increase in CD86 expression on CD14bright cells.The co-expression of CD80 and CD86 indicates effective antigen presentation to T cells and support of T helper cell differentiation.The selective expression of CD86 in the absence of CD80 points to a role in generating T regulatory cells.CONCLUSION:The data show that a primary mechanism of action of GBC30 metabolites involves support of more mature phenotypes of antigen-presenting cells,important for immunological decision-making.

Immune evasion strategies used by Helicobacter pylori

Helicobacter pylori(H. pylori) is perhaps the most ubiquitous and successful human pathogen, since it colonizes the stomach of more than half of humankind. Infection with this bacterium is commonly acquired during childhood. Once infected, people carry the bacteria for decades or even for life, if not treated. Persistent infection with this pathogen causes gastritis, peptic ulcer disease and is also strongly associated with the development of gastric cancer. Despite induction of innate and adaptive immune responses in the infected individual, the host is unable to clear the bacteria. One widely accepted hallmark of H. pylori is that it successfully and stealthily evades host defense mechanisms. Though the gastric mucosa is well protected against infection, H. pylori is able to reside under the mucus, attach to gastric epithelial cells and cause persistent infection by evading immune responses mediated by host. In this review, we discuss how H. pylori avoids innate and acquired immune response elements, uses gastric epithelial cells as mediators to manipulate host T cell responses and uses virulence factors to avoid adaptive immune responses by T cells to establish a persistent infection. We also discuss in this review how the genetic diversity of this pathogen helps for its survival.

Glucose initially inhibits and later stimulates blood ROS generation

Background: Glucose is the main substrate for the generation of NADPH, the cofactor of the oxidative burst enzyme NADPH-oxidase of blood neutrophils. Changes in blood glucose are thus expected to modify the generation of reactive oxygen species (ROS). The new blood ROS generation assay (BRGA) quantifies ROS changes induced by blood glucose concentrations as they are found in diabetes mellitus. Material and Methods: Citrated or EDTA blood of 6 healthy donors were analyzed in the BRGA: 10 μl sample in black polystyrene F-microwells (Brand 781608) were incubated in triplicate with 125 μl Hanks’ balanced salt solution, 40 μl 0 - 200 mM glucose in 0.9% NaCl (final added conc.: 0 - 41 mM;final basal glucose conc.: about4 mM), 10 μl5 mMluminol, and 10 μl zymosan A (final conc.: 1.9 μg/ml) in 0.9% NaCl. The plates were measured within 0 - 250 min (37℃) in a photons-multiplyer microtiter plate luminometer (LUmo) with an integration time of 1 s. Results: Up to about 30 min reaction time the mean ROS generation was 50% inhibited by about1 mMadded glucose (= approx. IC50). At ≥80 min reaction time (possibly necessary for full phosphorylation of glucose to glucose-6-phosphate (G6P), the substrate metabolized by G6P-dehydrogenase to generate NADPH, the cofactor of the NADPH-oxidase) the mean ROS generation approximately doubled at about1 mMadded glucose (= approx. SC200) in citrated blood. Discussion: Elevated glucose concentrations not only increase systemic thrombin generation, they can also diminish cellular fibrinolysis and increase systemic inflammation, resulting in a chronic pro-thrombotic state. The fascinating importance of NADPH-oxidases not only in phagocytes but also in the beta cells of pancreas points towards a new pathogenesis explication of diabetes mellitus type 1: whatever stimulus (e.g. a pancreas-tropic virus) could activate the beta cell’s autodestructive NADPH-oxidase.

Introduction of antineoplastic drug NSC631570 in an inpatient and outpatient setting:Comparative evaluation of biological effects

The aim of this study is to evaluate the effect of moderate physical exercise and treatment time on the organism’s response to NSC631570. The sensitivity of circulating phagocytes to the drug at different times of day was estimated in in vitro experiments. NSC631570 was administered intravenously to healthy volunteers (eleven men, 23 ± 2 years) in a single therapeutic dose in an inpatient and an outpatient setting. Blood samples were obtained before the drug administration, 30 min after the drug injection and every fourth hour throughout the 24 hour period. Biochemical parameters were determined using the hematological analyzer. Flow cytometry was used to evaluate phagocyte metabolism. Treatment of circulating phagocytes with NSC631570 in vitro resulted in an increase in ROS production along with a decrease in their phagocytic activity, most expressed in the morning time. Drug injection to sedentary persons resulted in pro-inflammatory metabolic polarization of circulating phagocytes. Introduction of NSC631570 to active persons was accompanied by a significant increase in phagocyte endocytosis along with a decrease in the daily mean of ROS generation. Significant oscillation (but in the normal ranges) of urea, creatinine, alanine aminotransferase and aspartate aminotransferase after NSC631570 introduction in the outpatient setting was shown during the day. Physical activity interferes with immunomodulatory action of NSC631570 and abrogates pro-inflammatory shift of circulating phagocytes. Biochemical parameters of blood from patients treated with NSC631570 in the outpatient setting must be interpreted cautiously considering the effect of physical activity on some metabolic biomarkers.

Cooperative apoptosis of coelomocytes of the holothurian <i>Eupentacta fraudatrix</i>and its modulation by dexamethasone

The capacities of phagocytes of subpopulation P1 (F) and morula cells (MC) of holothurian Eupentacta fraudatrix to modulate apoptosis of each other as well as cytokine-dependent mechanisms and hormonal regulation of these cells’s interaction were studied. The 18-h treatment of F with supernatants, obtained after centrifugation of MC preincubated for 3 h with phosphate buffered saline (PSB) at the temperature of 22℃?(SMC3) resulted in a significant growth of apoptosis level. A 30-min incubation of F with supernatants of MC, preincubated for 24 h (SMC24), on the contrary, reduced the apoptosis level and increased the level of interleukine-1α (IL-1α)-like substances, and 24-h incubation did not influence apoptosis and reduced level of IL-1α-like substances. Thus, proapoptotic effects of MC’s supernatants in F inversely depended on time of their preincubation with PSB and directly on time of incubation with F. Additionally, this effect was opposite to variations in the level of IL-1α-like substances. The level of apoptosis declined after 30 min of incubation but elevated after 24 h at the inverse treatment of MC with supernatant, obtained after preincubation of F during 24 h (SF24). The level of IL-1α-like substances dropped after 30 min and insignificantly decreased after 24 h. Hence, SF24 proapoptotic effect directly depended on time of incubation with MC and did not correspond to variations in the level of IL-1α-like substances. 100 μM dexamethasone stimulated apoptosis in F and MC in an inverse time-dependent manner during 24-h preincubation, and supernatants of cell suspensions obtained after such preincubations, stimulated apoptosis and reduced the IL-1α-like substances level in target cells at both types of interaction. IL-1α-like substances are?supposed to be mediators for MC’s effects in F, but not for F’s action on MC. In holothurians, steroid hormones apparently may participate in the regulation of the immune response and cell cooperation.

Granulocyte Colony—Stimulating Factor Multiplies Normal Blood ROS Generation at Less than 1 µg/l

Background: The neutrophils (PMN) are our main blood cells to combat fungi, bacteria, and fibrin. For normal function, an activated PMN generates a certain concentration of reactive oxygen species (ROS). If the generated blood ROS concentration is too low, then fungi, bacteria or fibrin might threaten the life of the patient, and it could be of great medical interest to stimulate PMN by physiologic drugs. Granulocyte-Colony Stimulating Factor (G-CSF) is a cell hormone that increases the cell number of PMN and that stimulates the individual PMN. The blood ROS generation assay (BRGA) is an innovative physiologic test to monitor the ROS generation of PMN in blood. Here the ROS generating action of G-CSF on normal PMN is quantified. Material and Methods: 40 &mu;l 0 - 10.3 ng/ml (final conc.) G-CSF (in 5% human albumin) in black Brand? 781608 high quality polystyrene F-microwells was incubated in triplicate with 125 &mu;l Hanks’ balanced salt solution (HBSS;modified without phenol red) and 10 μl normal citrated blood. Immediately (BRGA) or after 60 min (BRGA-60-) 10 &mu;l 5 mM luminol sodium salt in 0.9% NaCl and 10 &mu;l 0 or 36 &mu;g/ml zymosan A in 0.9% NaCl was added. The photons were counted within 0 - 318 min (37&deg;C) in a photons-multiplying microtiter plate luminometer. At about 0.5 t-maxn (0.5 fold the time to normal maximum) the approx. SC200 of G-CSF was determined. Results and Discussion: The approx. SC200 of G-CSF on normal blood ROS generation was 0.2 μg/l (=20 IU/ml). In clinical situations where an increased blood ROS generation is pharmacologically required, few micrograms of G-CSF could be a sufficient dosage for an adult patient. The BRGA helps to find out the correct stimulating G-CSF dosage for each individual. An enhanced PMN function could favor a better clinical outcome in situations of wanted increase of the innate immunology or in cellular fibrinolysis. G-CSF plasma concentrations of 0.1 - 1 &mu;g/l might favor singlet oxygen generation without immunosuppression or cell fragment-induced thrombin generation.

Studies on Antiviral and Immuno-Regulation Activity of Low Molecular Weight Fucoidan from Laminaria japonica

The antiviral activity in vitro and in vivo and the effect of the immune system of two fucoidan fractions with low molecular weight and different sulfate content from Laminaria japonica(LMW fucoidans) were investigated in order to examine the possible mechanism. In vitro, I-type influenza virus, adenovirus and Parainfluenza virus I were used to infect Hep-2, Hela and MDCK cells, respectively. And 50% tissue culture infective dose was calculated to detect the antiviral activity of two LMW fucoidans. The results indicated that compared with the control group, 2 kinds of LMW fucoidans had remarkable antiviral activity in vitro in middle and high doses, while at low doses, the antiviral activity of 2 kinds of LMW fucoidans was not statistically different from that in the blank control group. And there was no statistically difference between two LMW fucoidans in antiviral activity. In vivo, LMW fucoidans could prolong the survival time of virus-infected mice, and could improve the lung index of virus-infected mice significantly, which have statistical differences with the control group significantly(p < 0.01). However, the survival time of the two LMW fucoidans was not statistically significant(p > 0.05). In this study, it was shown that both of two LMW fucoidans(LF1, LF2) could increase the thymus index, spleen index, phagocytic index, phagocytosis coefficient and half hemolysin value in middle and high doses, which suggested that LMW fucoidans could play an antiviral role by improving the quality of immune organs, improving immune cell phagocytosis and humoral immunity.

Decreased phagocytic activity of Kupffer cells in a rat nonalcoholic steatohepatitis model

AIM: To investigate Kupffer cell dynamics and phagocytic activity,using a rat nonalcoholic steatohepatitis (NASH) model. METHODS: Male F344 rats were fed either a control diet or a choline-deficient L-amino acid-defined (CDAA) diet,followed by contrast enhanced ultrasonography (CEUS) using Levovist. The uptake of latex beads by the Kupffer cells was determined by fluorescent microscopy. The status of the Kupffer cells was compared between the two groups,using the immunohistochemical staining technique. RESULTS: After 4 or more wk of the CDAA diet,CEUS examination revealed a decrease in the signal intensity,20 min after intravenous Levovist. Fluorescent microscopic examination showed that the uptake of latex beads by the Kupffer cells was reduced at week 1 and 2 in the study group,compared with the controls,with no further reduction after 3 wk. Immunohistochemical staining revealed no significant difference in the Kupffer cell counts between the control group and the CDAA group. CONCLUSION: CEUS examination using Levovist demonstrated reduced contrast effect and phagocytic activity in the liver parenchymal phase,although the Kupffer cell numbers were unchanged,indicating reduced phagocytic function of the Kupffer cells in the rat NASH model. We believe that CEUS examination using Levovist is a useful screening modality,which can detect NASH in fatty liver patients.

Immunological Effect of PM_(2.5) on Cytokine Production in Female Wistar Rats

Objective To investigate the immunological effect of PM2.5 on cytokine production in female Wistar rats. Methods Female Wistar rats were given 0.3 mg, 0.75 mg, 2 mg, 5 mg of PM2.5 per 0.5 mL saline, respectively. Saline was used as the negative control. TNF-α and IL-6 levels in the branchoalveolar lavage were measured by ELISA, and mRNA expression levels in lung tissue were detected by RT-PCR. Alveolar macrophages were collected for testing phogacytic function. Results Exposure to PM2.5 stimulated TNF-α production in a dose-dependent manner （P〈0.05）, However, no statistically significant difference was found. No time-dependent change in TNF-α and IL-6 production was found. TNF-α and IL-6 mRNA expressions were induced by PM2.5-exposure. The phagocytic rate （PR） was significantly decreased by PM2.5 treatment. Conclusion PM2.5 exposure increases inflammation response of the lung in a dose-dependent manner. Moreover, tissue injury induced by PM2.5 may be related to altered production of cytokines. PM2.5 may impair the phagocytic activity of alveolar macrophages.

Preparation and in vitro Studies of Stealth PEGylated PLGA Nanoparticles as Carriers for Arsenic Trioxide

The aim of this study was to prepare arsenic trioxide （ATO）-loaded stealth PEGylated PLGA nanoparticles （PEG-PLGA-NPs） and to assess the merits of PEG-PLGA-NPs as drug carriers for ATO delivery. PEG-PLGA copolymer was synthesized with methoxypolyethyleneglycol （Mw=5000）, D, L-lactide, and glycolide by the ring-opening polymerization method. Amorphous ATO was transformed into cubic crystal form to increase its solu-bility in the organic solvent. ATO-loaded PEG-PLGA-NPs were prepared by the modified spontaneous emulsification solvent diffusion （SESD） method, and the main experimental factors influencing the characteristics of nanopar- ticles were investigated, to optimize the preparation. To confirm the escape of PEG-PLGA-NPs from phagocytosis by phagocytes, PEG-PLGA-NPs labeled rhodamine B uptake by murine peritoneal macrophages （MPM） were analyzed by flow cytometry. The results showed that the physicochemical characteristics of PEG-PLGA-NPs were affected by the type and concentration of the emulsifiers, polymer concentration, and drug concentration. ATO-loaded PEG-PLGA-NPs, with particle size of 120.8nm, zeta potential of-10.73mV, encapsulation efficiency of 73.6%, and drug loading of 1.36%, were prepared under optimal conditions. The images of transmission electron micros-copy （TEM） indicated that the optimized nanoparticles were near spherical and without aggregation or adhesion. The release experiments in vitro showed the ATO release from PEG-PLGA-NPs exhibited consequently sustained release for more than 26d, which was in accordance with Higuchi equation. The uptake of PEG-PLGA-NPs by MPM was found to decrease markedly compared to PLGA-NPs. The experimental results showed that PEG-PLGA-NPs were potential nano drug delivery carriers for ATO.

Impairment of innate immune responses in cirrhotic patients and treatment by branched-chain amino acids

It has been reported that host defense responses, such as phagocytic function of neutrophils and natural killer (NK) cell activity of lymphocytes, are impaired in cirrhotic patients. This review will concentrate on the impairment of innate immune responses in decompensated cirrhotic patients and the effect of the treatment by branched-chain amino acids (BCAA) on innate immune responses. We already reported that phagocytic function of neutrophils was significantly improved by 3-mo BCAA supplementation. In addition, the changes of NK activity were also significant at 3 mo of supplementation compared with before supplementation. Also, Fisher&#x02019;s ratios were reported to be significantly increased at 3 mo of BCAA supplementation compared with those before oral supplementation. Therefore, administration of BCAA could reduce the risk of bacterial and viral infection in patients with decompensated cirrhosis by restoring impaired innate immune responses of the host. In addition, it was also revealed that BCAA oral supplementation could reduce the risk of development of hepatocellular carcinoma in cirrhotic patients. The mechanisms of the effects will also be discussed in this review article.

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 IgC-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-4combined 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.

Microinjection of a growth factor cocktail affects activated microglia in the neocortex of adult rats

Microglia, as the resident immune cells in the central nervous system, play important roles in regulating neuronal processes, such as neural excitability, synaptic activity, and apoptotic cell clearance. Growth factors can activate multiple signaling pathways in central nervous system microglia and can regulate their immune effects, but whether growth factors can affect the morphological characteristics and ultrastructure of microglia has not been reported. After microinjecting 300 nL of a growth factor cocktail, including 10 μg/mL epidermal growth factor, 10 μg/mL basic fibroblast growth factor, 10 μg/mL hepatocyte growth factor and 10 μg/mL insulin-like growth factor into adult rat cortex, we found that the number of IBA1-positive microglia around the injection area increased significantly, indicating local activation of microglia. All CD68-positive labeling co-localized with IBA1 in microglia. Cell bodies and protrusions of CD68-positive cells were strongly attached to or were engulfing neurons. Characteristic huge phagosomes were observed in activated phagocytes by electron microscopy. The phagosomes generally included non-degraded neuronal protrusions and mitochondria, yet they contained no myelin membrane or remnants, which might indicate selective phagocytosis by the phagocytes. The remnant myelin sheath after phagocytosis still had regenerative ability and formed "myelin-like" structures around phagocytes. These results show that microinjection of a growth factor cocktail into the cerebral cortex of rodents can locally activate microglia and induce selective phagocytosis of neural structures by phagocytes. The study was approved by the Institute of Laboratory Animal Science, Beijing Institute of Basic Medical Sciences(approval No. IACUC-AMMS-2014-501) on June 30, 2014.

Immunomodulatory activity of butanol fraction of Gentiana olivieri Griseb. on Balb/C mice

Objective:To explore the immunomodulatory properties of 80% ethanol extract and butanol fraction of Gentiana olivieri(G. olivieri) Griseb on Balb/C mice.Methods:The study was performed with basic models of immunomodulation such as the humoral antibody response(hemoglutination antibody titres), cell mediated immune response(delayed type hypersensitivity and in vivocarbon clearance or phagocytosis). Ethanol(80%) extract of flowering aerial parts of G.olivieriand its butanol fraction were administered p.o.(orally) to the mice. Levamisole, 2.5 mg/kg was used as standard drug.Results:There was a potentiation of immune response to sheep red blood cells by cellular and humoral mediated mechanisms comparable to levamisole(2.5 mg/kg) by both 80% ethanol extract and the butanol fraction at doses of 50-200 mg/kg in male Balb/C mice. Both significantly(P<0.01) potentiated the humoral immune response in cyclophosphamide(250 mg/kg)immunosupressed mice at 100 and 200 mg/kg of each extract and fraction as compared to control.The potentiation of delayed type hypersensitivity response was statistically significant(P<0.01) at200 mg/kg of ethanol extract and 100, 200 mg/kg of butanol fraction as compared to control. The phagocytosis was significant at 200 mg/kg with butanol fraction ofG. olivieri.Conclusions:The results reveal the immunostimulant effects of plantG. olivieriin mice by acting through cellular and humoral immunity in experimental models of immunity in mice. Butanol fraction is the most effective at a dose level of 200 mg/kg.

The mononuclear phagocyte system in hepatocellular carcinoma

The mononuclear phagocyte system(MPS)consists of monocytes,dendritic cells and macrophages,which play vital roles in innate immune defense against cancer.Hepatocellular carcinoma(HCC)is a complex disease that is affected or initiated by many factors,including chronic hepatitis B virus infection,hepatitis C virus infection,metabolic disorders or alcohol consumption.Liver function,tumor stage and the performance status of patients affect HCC clinical outcomes.Studies have shown that targeted treatment of tumor microenvironment disorders may improve the efficacy of HCC treatments.Cytokines derived from the innate immune response can regulate T-cell differentiation,thereby shaping adaptive immunity,which is associated with the prognosis of HCC.Therefore,it is important to elucidate the function of the MPS in the progression of HCC.In this review,we outline the impact of HCC on the MPS.We illustrate how HCC reshapes MPS cell phenotype remodeling and the production of associated cytokines and characterize the function and impairment of the MPS in HCC.