Macrophage activation and nitric oxide production by water soluble components of Hericium erinaceum

Changes in the component sugar and immunostimulating activity of polysaccharides isolated from Dendrobium officinale in the pretreatments

BACKGROUND

To isolate polysaccharides with enhanced immunostimulatory activity from Dendrobium officinale, which is used as a herbal medicine in China and Southeast Asia, D. officinale (DO) was pretreated with organic solvents (DOOS) or puffing at 7.5 and 9.0 kg_f (7.5DO and 9DO). Hot-water extracts (DOOS-HW, 7.5DO-HW and 9DO-HW) were prepared from each pretreated DO, along with non-pretreated DO, and crude polysaccharides (DO-CP, DOOS-CP, 7.5DO-CP and 9DO-CP) were fractionated from each hot-water extract using ethanol (five volumes).

RESULTS

When their immunostimulatory activities were compared by macrophage stimulation and intestinal immune system modulation via Peyer's patches, DOOS-CP showed more potent activity than DO-CP. However, crude polysaccharides fractionated from puffed DO showed significantly lower activity than non-puffed DO and DOOS. The most active polysaccharide contained 95% or more neutral sugar, and the composition ratio of mannose and glucose was 3.0, whereas the lowest polysaccharide content was 2.0 or less. In addition, DOOS-CP was a somewhat refined fraction containing a major peak, representing a molecular weight of 250 kDa, despite being a crude polysaccharide.

CONCLUSION

These results suggest that pretreatment of D. officinale with organic solvents may enhance the immunostimulatory activity of polysaccharides and affect the mannose/glucose ratio of polysaccharides, which plays an important role in immunostimulation. © 2021 Society of Chemical Industry.

Immunomodulatory activity of ethanol extract of Annona reticulata L. leaf in cultured immune cells and in Swiss albino mice

Background

Annona reticulata Linn, has been shown to possess antipyretic, antihelmintic, hypoglycemic, antiulcer and wound healing properties. However, its immunomodulatory role is yet to be explored.

Objective(s)

In the present study, we intended to investigate the effects of A. reticulata leaf ethanol extract on various components of the immune system.

Material and methods

The effects of A. reticulata leaf extract on human peripheral blood mononuclear cells, monocyte (THP1), and human macrophage (U937) cell lines were investigated. An animal study was conducted to observe the effect of the extract on humoral as well as cell mediated immunity.

Results

The extract stimulated proliferation of human PBMC, monocytes (THP1), and macrophages (U937) significantly in a dose dependent manner; expression of transforming growth factor-beta (TGF-β) increased in western blot analysis. Additionally, the extract treated macrophages exhibited features of activation under the microscope with a significant hike in the NO production. Flow cytometry of extract treated human PBMC revealed increased proliferation of lymphocytes (CD4, CD8 & B-cells) along with enhanced intracellular expression of IL-2, IL-6. Animal study data indicate a significant rise in the antibody titer as well as a strong delayed type hypersensitivity response in the extract (150 mg/kg and 300 mg/kg) treated mice; furthermore, the expression of IL-2 and IL-6 in mice PBMC was augmented.

Conclusion

The collective data evince the immunomodulatory potential of A. reticulata L. leaf.

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Annona reticulata L. stimulates proliferation of human PBMC, monocytes, and macrophages significantly.

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The extract activates cultured macrophages (U937).

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The extract enhanced lymphocyte proliferation along with expression of interleukins in human PBMC.

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Extract treated mice revealed a strong DTH response with significant rise in the antibody titer.

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The expression of IL-2 and IL-6 in mice PBMC was augmented in the treated group.

Characterization and immunomodulatory activity of sulfated galactan from the red seaweed Gracilaria fisheri

Polysaccharides from the red seaweed Gracilaria fisheri possess many functions, which include antioxidant, antiviral, and antibacterial activities. However, detailed data on their immunomodulatory activities are scarce. Here, we isolated sulfated galactans (SG) from G. fisheri. We found that the predominant SG from G. fisheri, termed SG-1, had an estimated molecular mass of 100 kDa and activated murine J774A.1 macrophages via the dectin-1 signaling pathway. Furthermore, we observed enhancement of nitric oxide (NO) secretion, increased expression of inducible nitric oxide synthase (iNOS) mRNA, and increased mRNA levels of pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α) and interleukins IL-1β and IL-6 by SG-1 in macrophages. Moreover, there was higher expression of intercellular adhesion molecule 1 (ICAM-1) and co-stimulatory molecules (B7-1 and B7-2) mRNA. Treatment with G. fisheri SG-1 at 50 μg/mL generally achieved or exceeded the pro-inflammatory activities of 100 ng/mL lipopolysaccharide. Our study demonstrates immune-stimulatory activities of G. fisheri SG that may be of value for immune-potentiating treatment in humans or livestock.

Synergy Effects of Three Plant Extracts on Protection of Gastric Mucosa

The gastric mucosa protection effect of three natural plant extracts, Hericium erinaceus (HE), Centella asiatica (CA) and Amomum villosum (AV), were evaluated using the indomethacin damage model. Compared with a single extract, a combination of HE/CA/AV, especially with the ratios of 80:10:10, 45:45:10 and 45:10:45, showed significant synergistic effects for protection of the gastric mucosa with gastric ulcer inhibition rates of 97.8 ± 0.7%, 86.5 ± 2.8% and 86.1 ± 3.6%, respectively. Microscopic appearances of the gastric mucosa were carried out to help confirm the results.

Medicinal properties of Hericium erinaceus and its potential to formulate novel mushroom-based pharmaceuticals

Hericium erinaceus is an important mushroom with edible values and medicinal properties. Both the mycelium and the fruiting bodies contain many bioactive compounds with drug efficacy. Recent evidence demonstrates that it is helpful to various diseases, such as Alzheimer's disease, immunoregulatory, and many types of cancer. Furthermore, emerging pieces of evidence have shown that different active molecules in H. erinaceus have different functions on different organs in different diseases via the different mechanisms. Drawing on current research results, this review mainly focuses on the therapeutic effects of H. erinaceus on various diseases of multiple physiological systems, including the nervous system, digestive system, circulatory system, and immune system. This paper also discusses systematically the efficient protection of H. erinaceus against the diseases from the intricate experimental proofs by using the systematic viewpoints, which provides a framework for future research directions.

Immunopotentiation of Pleurotus eryngii (DC. ex Fr.) Quel

ETHNOPHARMACOLOGICAL RELEVANCE

Pleurotus eryngii (DC. ex Fr.) Quel has been collected from the wild, cultivated and used in traditional medicines to treat various disorders and diseases since antiquity. In traditional Chinese medicine, the powdered fruiting bodies of Pleurotus eryngii were used for immunostimulation, skin-care, wound-healing, cancer and lumbago treatment. In the current study, we investigated the antiproliferative activity of Pleurotus eryngii powder on A549, BGC-823, HepG2 and HGC-27 cancer cells and its immunomodulating activity on macrophage, RAW 264.7 cells based on its active compound.

MATERIALS AND METHODS

A novel bioactive protein (PEP) was extracted from Pleurotus eryngii fruiting bodies powder and purified on DEAE-52, CM-52 and Superdex 75 column chromatographies using an ÄKTA purifier. Its cytotoxicity on A549, BGC-823, HepG2, HGC-27 and RAW 267.4 cell lines was then evaluated using MTT, alamar blue (AB), trypan blue (TB), neutral red (NR), lactate dehydrogenase (LDH), Annexin V FITC/PI and morphological change assays. Moreover, lysosomal enzyme activity, pinocytosis, nitric oxide (NO) and hydrogen peroxide (H₂O₂) production assays were used to examine immunomostimulatory activity of PEP on RAW 267.4 cells.

RESULTS

Based on high performance gel permeation chromatography (HPGPC), Fourier transform infrared (FT-IR) and nuclear magnetic resonance (NMR) analyses, the isolated protein (PEP) had a molecular weight of 63 kDa, a secondary (α-helical) structure and was mainly composed of arginine, serine and glycine. PEP significantly (P<0.05) inhibited A549, BGC-823, HepG2 and HGC-27 tumor cells proliferation dose-dependently with an IC₅₀ range of 36.5 ± 0.84 to 229.0 ± 1.24 µg/ml. Contrarily, PEP stimulated the proliferation of macrophages.

CONCLUSION

Pleurotus eryngii fruiting bodies powder has a potential application as a natural antitumor agent with immunomodulatory activity, proposedly, by targeting the lysosomes of cancerous cells and stimulating macrophage-mediated immune responses.

Hericium erinaceus (Yamabushitake): a unique resource for developing functional foods and medicines

This article provides valuable scientific information for Hericium erinaceus and shows its potential for the development of new functional foods and drugs.

Analgesic Activity of a Glucan Polysaccharide Isolated from Agaricus blazei Murill

A water soluble polysaccharide and its selective precipitated fractions (F1, F2, and F3) were isolated from hot water extract of fruiting bodies of Agaricus blazei Murril known as Agaricus brasiliensis to evaluate the analgesic activity of the materials in Swiss mice. The isolated material and its fractions were characterized by two-dimensional COSY and HMQC spectra as β-(1→6)-α-(1→4)-glucan-bound-protein polysaccharide constituted mainly by β-(1→6) glucan. The glucan-protein polysaccharide and its fractions were analyzed in relation to the protein, carbohydrate, and mineral elements contents. The analysis of the glucan-protein complex revealed a total carbohydrate content of 36.95% and protein conjugated content of 17.24%. The mineral elements found in larger proportion were K, Na, Ca, P, and Zn. The analgesic activity bioassay of the β-(1→6)-α-(1→4)-glucan bound-protein polysaccharide and its fractions in Swiss mice indicated a significant effect.

A smaller particle size improved the oral bioavailability of monkey head mushroom, Hericium erinaceum, powder resulting in enhancement of the immune response and disease resistance of white shrimp, Litopenaeus vannamei

The effects of different particle sizes (100-150, 74-100, and <74 μm) of powder of the dried and ground stipe from the monkey head mushroom, Hericium erinaceum, on the immune response and disease resistance of white shrimp, Litopenaeus vannamei, against the pathogen, Vibrio alginolyticus, were examined. Mushroom powder with a particle size of <74 μm had a significantly higher effect on the disease resistance of shrimp compared to particle sizes of >74 μm. Mortality of shrimp after being injected with V. alginolyticus was particle size-dependent, increasing from 66.7% ± 3.3%-93.3% ± 3.3% with diets containing stipe particle sizes of <74 and 100-150 μm, respectively. The mortality of shrimp fed the diet containing <74-μm stipe powder for 28 days was significant lower than that of shrimp fed with the control diet and the diet containing 74-100-μm stipe powder after being challenged by V. alginolyticus. The optimal concentration of the <74-μm mushroom powder for enhancing the immune response and disease resistance of shrimp was 0.2 μg (g shrimp)(-1) day(-1). No significant change in the total hemocyte count, differential hemocyte count, glutathione reductase, or phagocytic activity was found in shrimp fed the control diet and mushroom powder-containing diet at a level of up to 0.2 μg (g shrimp)(-1) day(-1). Shrimp fed 0.2 μg (g shrimp)(-1) day(-1) of a mushroom-containing diet had a significantly higher disease resistance to V. alginolyticus via an increase in phenoloxidase activity, respiratory bursts, superoxide dismutase activity, and glutathione peroxidase activity. Therefore, a diet containing the stipe powder of monkey head mushroom with a particle size <74 μm at a level of 0.2 μg (g shrimp)(-1) day(-1) was found to enhance the immunity and disease resistance of shrimp.

Immunostimulating activity by polysaccharides isolated from fruiting body of Inonotus obliquus

In this study, we investigated the immunostimulating activity of polysaccharides isolated from fruiting body of Inonotus obliquus (PFIO). Additionally, the signaling pathway of PFIO-mediated macrophage activation was investigated in RAW264.7 macrophage cells. We found that PFIO was capable of promoting NO/ROS production, TNF-α secretion and phagocytic uptake in macrophages, as well as cell proliferation, comitogenic effect and IFN-γ/IL-4 secretion in mouse splenocytes. PFIO was able to induce the phosphorylation of three MAPKs as well as the nuclear translocation of NF-κB, resulting in activation of RAW264.7 macrophages. PFIO also induced the inhibition of TNF-α secretion by anti-TLR2 mAb, consequently, PFIO might be involved in TNF-α secretion via the TLR2 receptor. In addition, our results showed that oral administration of PFIO suppressed in vivo growth of melanoma tumor in tumorbearing mice. In conclusion, our experiments presented that PFIO effectively promotes macrophage activation through the MAPK and NF-κB signaling pathways, suggesting that PFIO may potentially regulate the immune response.

Induction of intercellular adhesion molecule-1 by water-soluble components of Hericium erinaceum in human monocytes

AIM OF THE STUDY

Hericium erinaceum is a medicinal mushroom that has been traditionally used in Asian countries for the treatment of cancers and infectious diseases. Although the immunomodulating activity of H. erinaceum is considered to be responsible for its medicinal activity, its action mechanisms are poorly understood. In the present study, we investigated the capability of water-extracted H. erinaceum (WEHE) to induce the expression of intercellular adhesion molecule-1 (ICAM-1), which regulates the migration of immune cells.

MATERIALS AND METHODS

THP-1, a human monocytic cell-line, or human peripheral blood mononuclear cells (PBMC) were stimulated with WEHE (0-30 μg/mL) and subsequently analyzed using flow cytometry to examine the surface expression of ICAM-1 protein. Steady-state levels of ICAM-1 mRNA were estimated using real-time reverse transcription-polymerase chain reaction analysis. Electrophoretic mobility shift assay was conducted to examine transcription factors involved in ICAM-1 transcription.

RESULTS

WEHE induced ICAM-1 expression at both protein and mRNA levels in THP-1 cells in a dose- and time-dependent fashion. A similar pattern of ICAM-1 induction was also observed in CD14(+) monocytes in human PBMC that were stimulated with WEHE. The ICAM-1 expression on THP-1 cells stimulated with WEHE was suppressed by specific inhibitors for extracellular signal-regulated kinases (ERK) and reactive oxygen species (ROS). Additionally, exposure of THP-1 cells to WEHE increased the DNA binding activities of NF-κB, AP-1, SP-1 and STAT-1 transcription factors, all of which are known to be required for ICAM-1 gene expression.

CONCLUSIONS

These results suggest that WEHE induces ICAM-1 expression in human monocytes through ERK- and ROS-dependent signaling pathways, resulting in the subsequent activations of NF-κB, AP-1, SP-1, and STAT-1 transcription factors.

Toxicological study on MUNOPHIL, water extract of Panax ginseng and Hericium erinaceum in rats

OBJECTIVE

As data on the safety profile of Panax ginseng and Hericium erinaceum is lacking, the safety of these two compounds was examined in a series of toxicological studies.

MATERIALS AND METHODS

MUNOPHIL, the water extract mixture of Panax ginseng and Hericium erinaceum was tested in an oral subchronic 28-day toxicity study in rats at doses of 1250, 2500 and 5000 mg/kg/day.

RESULTS

In repeated dose toxicity studies, no mortality was observed when varying doses of the extracts were administered once daily for a period of 28 days. There were no significant differences in body weight, absolute and relative organ weights between controls and treated rats of both sexes. Hematological analysis showed no differences in most parameters examined. In the biochemistry parameter analysis, no significant change occurred. Pathologically, neither gross abnormalities nor histopathological changes were observed. Therefore, MUNOPHIL appears to be safe and non-toxic in these studies and a no-observed adverse effect level in rats was established at 5000 mg/kg/day.

CONCLUSION

The data could provide satisfactory preclinical evidence of safety to launch clinical trials on standardized formulation of plant extracts.

Integrative Tumor Board: A Case Report and Discussion From East-West Cancer Center

Aim. To introduce the application of wheel balance cancer therapy (WBCT) in cancer treatment through an intensive study of a representative patient. Method. A 59-year-old, female patient who was a secondhand smoker and who carried no significant medical and family history was diagnosed with T1N0M1 (stage 4) lung adenocarcinoma. Immunohistochemistry was positive for thyroid transcription factor-1, CK7, cyclin D1, p53, and Ki-67 on both lung biopsy specimens. An open lobectomy with mediastinal nodal dissection followed. The patient was transferred to East-West Cancer Center (EWCC) suffering from exertional dyspnea (NYHA [New York Heart Association] grade 2) with thoracic pain and pain in both upper limbs because of the decreased ventilatory capacity and reduced exercise capacity after a pulmonary resection. She also complained of emotional stress. EWCC provided WBCT, a multimodality alternative protocol based on the theory of traditional oriental medicine. Physicians regularly monitored whether metastasis or recurrence existed through blood and radiation tests. Observations and dialogues with the patient were used to record the changes in symptoms such as thoracic pain, dyspnea, anxiety, and fear. Results . Treatments at EWCC led to a disease-free survival of 28 months without adjuvant chemotherapy. Neither metastasis nor recurrence occurred during this period. Exertional dyspnea recovered to NYHA grade 1. Other physical and psychological symptoms were alleviated. Conclusion. This report suggests that WBCT may have the potential for extending life expectancy, controlling symptoms, and improving quality of life in cancer patients.

Induction of ICAM-1 by Armillariella mellea is mediated through generation of reactive oxygen species and JNK activation

ETHNOPHARMACOLOGICAL RELEVANCE

Armillariella mellea is an edible mushroom that has been traditionally used as an alternative medicine in many countries because of its anti-microbial and anti-cancer effects.

AIM OF THE STUDY

In this study, we examined the ability of Armillariella mellea to induce the expression of intercellular adhesion molecule (ICAM)-1, an important cellular adhesion molecule for the recruitment of immune cells to regional inflammatory sites.

MATERIALS AND METHODS

A human monocytic cell line, THP-1 or human peripheral blood mononuclear cells (PBMC) were stimulated with Armillariella mellea extract (AME) and subjected to flow cytometry to examine the expression of ICAM-1 protein on the cell surface. Steady-state mRNA level of ICAM-1 was determined by real-time reverse transcription-polymerase chain reaction. The phosphorylation of JNK protein was examined by Western blot analysis using antibodies specific for non-phosphorylated and phosphorylated forms of JNK. For the analysis of transcription factors regulating ICAM-1 transcription, the nuclear fraction was extracted from AME-treated THP-1 cells and subjected to electrophoretic mobility shift assay.

RESULTS

AME induced expression of ICAM-1 and its mRNA in THP-1 cells in dose- and time-dependent manners. AME-induced ICAM-1 expression was also observed on CD14-positive monocytes in human PBMC. Interestingly, AME-induced ICAM-1 production was inhibited by the specific inhibitors of reactive oxygen species (ROS) and JNK, whereas no inhibitory effect was observed when inhibitors of ERK, p38 kinase, phosphatidylinositol 3-kinase, or protein kinase C were used. Concomitantly, AME increased phosphorylation of JNK in a time-dependent fashion. DNA binding activities of NF-kappaB, AP-1, SP-1, and STAT-1 were increased by AME treatment.

CONCLUSION

These results suggest that AME induces ICAM-1 expression in human monocytic cells through ROS/JNK-dependent signaling pathways leading to the activation of NF-kappaB, AP-1, SP-1, and STAT-1 transcription factors.

An ethanol extract of Piper betle Linn. mediates its anti-inflammatory activity via down-regulation of nitric oxide

The leaves of Piper betle (locally known as Paan) have long been in use in the Indian indigenous system of medicine for the relief of pain; however, the underlying molecular mechanisms of this effect have not been elucidated. The anti-inflammatory and immunomodulatory effects of an ethanolic extract of the leaves of P. betle (100 mg kg−1; PB) were demonstrated in a complete Freund's adjuvant-induced model of arthritis in rats with dexamethasone (0.1 mg kg−1) as the positive control. At non-toxic concentrations of PB (5–25 μg mL−1), a dose-dependent decrease in extracellular production of nitric oxide in murine peritoneal macrophages was measured by the Griess assay and corroborated by flow cytometry using the nitric oxide specific probe, 4,5-diaminofluorescein-2 diacetate. This decreased generation of reactive nitrogen species was mediated by PB progressively down-regulating transcription of inducible nitric oxide synthase in macrophages, and concomitantly causing a dose-dependent decrease in the expression of interleukin-12 p40, indicating the ability of PB to down-regulate T-helper 1 pro-inflammatory responses. Taken together, the anti-inflammatory and anti-arthrotic activity of PB is attributable to its ability to down-regulate the generation of reactive nitrogen species, thus meriting further pharmacological investigation.

Paeonia japonica, Houttuynia cordata, and Aster scaber water extracts induce nitric oxide and cytokine production by lipopolysaccharide-activated macrophages

Natural products are increasingly recognized as potential targets for drug discovery and development. We previously reported that Paeonia japonica, Houttuynia cordata, and Aster scaber enhanced macrophage activation both in vitro and in vivo. In the present study we investigated the immunomodulating effects of these plants on lipopolysacharide (LPS)-stimulated macrophages. An aqueous extract of each plant was administered to female BALB/c mice every other day for 4 weeks. Peritoneal macrophages were then collected and incubated to examine the immunoreactivity of macrophages against LPS at different time points. The expression levels of inducible nitric oxide (NO) synthetase (iNOS), cyclooxygenase (COX)-2, and inhibitory factor kappaB alpha (IkappaBalpha) proteins and the production of NO metabolite (nitrite), prostaglandin (PG) E(2), and the pro-inflammatory cytokines interleukin-1beta, interleukin-6, and tumor necrosis factor-alpha were determined in the activated macrophages treated with extracts from each plant individually or combined. High levels of pro-inflammatory cytokines were produced by A. scaber-, P. japonica-, and H. cordata-treated macrophages following 24 hours of LPS stimulation. P. japonica, H. cordata, and A. scaber treatment also induced the production of nitrate by LPS-treated macrophages. Induction of iNOS mRNA and protein was also different in each group. PGE(2) secretion was up-regulated by all extract-treated macrophages at early time points; however, no significant differences were observed between the groups by 8 hours post-LPS stimulation. Treatment with A. scaber extract resulted in the highest levels of IkappaBalpha degradation. Our findings illustrate that the natural plant products P. japonica, H. cordata, and A. scaber may enhance immune function by modulating ex vivo pro-inflammatory cytokine and NO production as well as the expression of iNOS and COX-2.

A novel beta-glucan produced by Paenibacillus polymyxa JB115 induces nitric oxide production in RAW264.7 macrophages

The effect of extracellular β-(1→3), (1→6)-glucan, produced by Paenibacillus polymyxa JB115, on nitric oxide (NO) production in RAW264.7 macrophages was investigated. β-glucan induced the production of NO by RAW264.7 macrophages in a concentration- and time-dependent manner. Moreover, β-glucan stimulation increased the mRNA expression of iNOS, COX-2 and IL-6 in RAW264.7 macrophages in a concentration-dependent manner.

Extract from Calotropis procera latex activates murine macrophages

Calotropis procera latex has long been used in traditional medicines. Extracts from C. procera latex have been reported to have various pharmacological actions, including protection from myocardial infarction, hepatoprotective action, antitumor activity, antinociceptive, and pro- and anti-inflammatory actions. To evaluate the immunomodulatory functions of the water-soluble C. procera extract (CPE), we investigated its ability to activate macrophages-effector cells in inflammatory and immune responses. Intraperitoneal injection of CPE in mice (2 mg/mouse) induced migration of macrophages to the intraperitoneal cavity, confirming the proinflammatory effects of water-soluble CPE. The direct effects of CPE on macrophages were then assessed by measuring the production of nitric oxide (NO) as an indicator for macrophage activation. Addition of CPE (1-10 microg/ml) to the culture medium of the murine monocyte/macrophage cell line RAW264.7 caused an increase in NO production in a time- and dose-dependent manner. CPE-elicited NO production was blocked by application of an inhibitor of inducible nitric oxide synthase (iNOS). Expression of iNOS mRNA was induced by treatment of cultured macrophages with CPE. Injection of CPE in mice also resulted in an increase in plasma NO level. The results suggest that CPE activates macrophages and facilitates NO production via up-regulation of iNOS gene expression.

Armillariella mellea induces maturation of human dendritic cells without induction of cytokine expression

ETHNOPHARMACOLOGICAL RELEVANCE

Armillariella mellea, an edible and medicinal mushroom possessing immuno-modulating potential, has been frequently used for the treatment of infectious diseases or cancers.

AIM OF THE STUDY

In order to elucidate immune-regulatory mechanisms of Armillariella mellea, we investigated the effect of water-soluble components from Armillariella mellea (AME) on the regulation of human dendritic cell (DC) maturation and activation.

MATERIALS AND METHODS

Immature DCs (iDCs) were prepared by differentiating human peripheral blood CD14-positive cells with GM-CSF and IL-4. Then, iDCs were treated with AME at 2-20 microg/ml for 48 h and subjected to flow cytometry to analyze the expression of DC markers. Dextran-FITC uptake assay and enzyme-linked immunosorbent assay were performed to examine the endocytic capacity of AME-stimulated DC and their production of cytokines, respectively.

RESULTS

iDCs stimulated with AME showed representative features during DC maturation such as up-regulated expression of CD80, CD83, CD86, both MHC class I and II molecules, and CD205, with a simultaneous decrease in the expression of CD206 and the endocytic capacity. Interestingly, AME was not able to induce the production of TNF-alpha, IL-12p40, or IL-10, whereas lipopolysaccharides induced a substantial increase of all of the cytokines.

CONCLUSION

Armillariella mellea induces maturation of human DCs through a unique mechanism without inducing cytokine expression.

Soluble components of Hericium erinaceum induce NK cell activation via production of interleukin-12 in mice splenocytes

AIM

To investigate the immunoregulatory functions of water extracts of Hericium erinaceum (WEHE) focusing on natural killer (NK) cell-based anticancer activities.

METHODS

Mouse splenocytes or purely isolated NK cells were stimulated with 1-100 mg/L WEHE for 24 h followed by co-culture with (51)Cr-labeled Yac-1 cells for 4 h, then NK cell-derived cytolytic activity was measured using a radio-release assay. Neutralizing antibodies against mouse interleukin-12 (IL-12) were added into the WEHE-stimulated splenocytes, thereafter, cytotoxicity was measured to examine the involvement of IL-12. RT-PCR and ELISA analyses were performed to confirm the induction of transcription and the translation of IL-12 and interferon-gamma (IFN-gamma) in the WEHE-treated splenocytes.

RESULTS

WEHE enhanced the cytolytic activity of total splenocytes towards Yac-1 cells in a dose-dependent manner. However, this activation was not observed when the NK cells isolated from the splenocytes were treated with WEHE. Furthermore, the treatment with antibodies against IL-12 abolished the effect of WEHE on splenocyte-derived cytolytic activity. RT-PCR and ELISA analyses showed the induction of IL-12 and IFN-gamma in the WEHE-treated splenocytes.

CONCLUSION

WEHE indirectly activates the cytolytic ability of NK cells via the induction of IL-12 in total splenocytes, and possibly via other immuno-mediators or cellular components.