Evaluation of widely consumed botanicals as immunological adjuvants

Adjuvant activities of immunostimulating natural products: Astragalus membranaceus (Fisch.) Bge. and Coriolus versicolor in BNT162b2 vaccination against COVID-19 infection

The global pandemic of COVID-19, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been developing all over the world for more than 3 years. In late 2020, several variants of concern of SARS-CoV-2 virus emerged, with increased viral fitness and transmissibility by mutations of the spike proteins of the viral particle, denting hopes of the use of early-generation vaccines for a widespread protective immunity against viral infection. The use of adjuvants may enhance the immune responses of the conventional application of the COVID-19 vaccine. We have shown that the water extract of 2 β-glucan-enriched immunostimulating natural products, Astragalus membranaceus (Fisch.) Bge. (AM) and Coriolus versicolor (CV), could induce innate immunity-related cytokines from human monocytes (CCL5, interleukin [IL]-6, IL-10, and tumor necrosis factor α) and monocyte-derived dendritic cells (IL-1β, IL-10, IL-12, and tumor necrosis factor α). Using BALB/c mice, orally administrated AM and CV (1,384 and 742 mg/kg/d) for 4 d after vaccination, respectively, could enhance (1) the immunoglobulin G binding activities of BNT162b2 vaccination against ancestral and Delta SARS-CoV-2 spike proteins by 5.8- and 4.3-fold, respectively; (2) the immunoglobulin G3 subclass production of BNT162b2 vaccination against ancestral and variant SARS-CoV-2 spike proteins; and (3) the in vitro antibody-neutralizing activities of BNT162b2 vaccinated mice. In conclusion, combining AM and CV was effective in acting as an oral adjuvant with the messenger RNA vaccine BNT162b2 to improve the antigen binding activities against SARS-CoV-2 ancestral and variant SARS-CoV-2 spike proteins, probably via trained immunity of macrophages and dendritic cells.

Creating a Vaccine-like Supplement against Respiratory Infection Using Recombinant Bacillus subtilis Spores Expressing SARS-CoV-2 Spike Protein with Natural Products

Vaccination is the most effective method of combating COVID-19 infection, but people with a psychological fear of needles and side effects are hesitant to receive the current vaccination, and alternative delivery methods may help. Bacillus subtilis, a harmless intestinal commensal, has recently earned a strong reputation as a vaccine production host and delivery vector, with advantages such as low cost, safety for human consumption, and straightforward oral administration. In this study, we have succeeded generating "S spores" by engineering B. subtilis with spore coat proteins resembling the spike (S) protein of the ancestral SARS-CoV-2 coronavirus. With the addition of two immunostimulating natural products as adjuvants, namely Astragalus membranaceus (Fisch.) Bge (AM) and Coriolus versicolor (CV), oral administration of S spores could elicit mild immune responses against COVID-19 infection without toxicity. Mucosal IgA against the S protein was enhanced by co-feeding with AM and CV in an S spores-inoculated mouse model. Faster and stronger IgG responses against the S protein were observed when the mice were fed with S spores prior to vaccination with the commercial COVID-19 vaccine CoronaVac. In vitro studies demonstrated that AM, CV, and B. subtilis spores could dose-dependently activate both macrophages and dendritic cells by secreting innate immunity-related IL-1β, IL-6, and TNF-α, and some other proinflammatory chemokines and cytokines. In conclusion, the combination of S spores with AM and CV may be helpful in developing a vaccine-like supplement against respiratory infection.

Phytochemical profile, comparative evaluation of Satureja montana alcoholic extract for antioxidants, anti-inflammatory and molecular docking studies

BACKGROUND

The most common species in the Satureja genus is Satureja montana (family Lamiaceae). The present work aims to use the molecular docking study to predict the isolated constituents against an immune system immunomodulator and tested alcoholic extract as an in-vitro immunomodulatory agent.

METHODS

All isolated compound's structures were determined using various chromatographic and spectroscopic techniques. Anti-inflammatory and antioxidant profiles were studied for an alcoholic extract of the plant; the molecular docking study was performed for the isolated compounds (1-4).

RESULTS

In this work, four recognized compounds were extracted from the ethyl acetate fraction of S. montana (Sm) methanolic extract and identified as two triterpenes ursolic acid (1) and oleanolic acid (2), one phenolic acid as ellagic acid (3), and one flavonoidal compound as isoscutellarein (4). The total alcoholic extract exhibited good in vitro anti-inflammatory, antioxidant, and apoptotic activity. Its IC₅₀ was 10.12 compared to 15.1 μg/ml of standard celecoxib. It also showed potent antioxidant activity with IC₅₀ 10.4, 11.3, 14.6, and 22.3 IU/ml for SOD, MDA, catalase, and TAC, respectively. According to the drug similarity and ADMET tests, their ligands may have favorable pharmacokinetic characteristics with minimal carcinogenic influence. The molecular docking study was performed for the isolated compounds (1-4).

CONCLUSIONS

The alcoholic extract of the plant showed promising anti-inflammatory, antioxidant, and antiapoptotic properties. The theoretical studies for the isolated compounds showed promising binding affinity against all the examined enzymes.

Effect of Oral β-Glucan on Antibody Response to Ganglioside Vaccine in Patients With High-Risk Neuroblastoma: A Phase 2 Randomized Clinical Trial

Importance

Among patients with high-risk relapsed metastatic neuroblastoma, oral β-glucan adjuvant during GD2/GD3 ganglioside vaccine boost has stimulated IgG antibody response, which was associated with improved survival; however, the effectiveness of oral β-glucan during the vaccine priming phase remains unproven.

Objective

To isolate the adjuvant effect of oral β-glucan on antibody response to GD2/GD3 ganglioside vaccine in patients with high-risk neuroblastoma.

Design, Setting, and Participants

In this phase 2 randomized clinical trial, enrolled patients with high-risk neuroblastoma were randomized to 2 groups to receive the GD2/GD3 vaccine at a large cancer center in a major metropolitan area from October 2018 to September 2020. Data were analyzed from October 7, 2021, to February 28, 2022.

Interventions

Eligible patients receiving GD2/GD3 vaccine were randomly assigned to group 1 (n = 54) to receive no β-glucan or group 2 (n = 53) to receive an oral β-glucan regimen during the first 5 weeks of vaccine priming. From week 6 onwards, all 107 patients received oral β-glucan during vaccine boost for 1 year or until disease progression.

Main Outcomes and Measures

Primary end point was comparison of anti-GD2 IgG1 response before vaccine injection 6 (week 32) in group 1 vs group 2. Seroconversion rate and the association of antibody titer with β-glucan receptor dectin-1 single nucleotide polymorphism (SNP) rs3901533 were also assessed.

Results

In all, 107 patients with high-risk neuroblastoma were randomized to the 2 groups: 54 patients (median [range] age, 5.2 [1.0-17.3] years; 28 [52%] male and 26 [48%] female) in group 1; and 53 patients (median [range] age, 6.2 [1.9-18.4] years; 25 [47%] male and 28 [53%] female) in group 2; both groups were also comparable in their first remission status at study entry (70% vs 70%). Adding oral β-glucan during the first 5 weeks of vaccine priming elicited a higher anti-GD2 IgG1 antibody response in group 2 (1.80; 90% CI, 0.12-3.39; P = .08; planned type I error, 0.10). Anti-GD2 IgG1 titer of 230 ng/mL or greater by week 8 was associated with statistically favorable PFS. Antibody titer correlated significantly with dectin-1 SNP. The genotype frequency, seroconversion rates, and vaccine-related toxic effects were similar in the 2 groups.

Conclusions and Relevance

This phase 2 randomized clinical trial found that adding oral β-glucan during vaccine priming increased anti-GD2 IgG1 titer among genetic responders without added toxic effects. Because responder dectin-1 SNP was identical in the 2 randomized groups, no difference was detected in seroconversion rates. Alternative or additional adjuvants may be needed to enhance seroconversion.

Trial Registration

ClinicalTrials.gov Identifier: NCT00911560.

Coriolus versicolor and its bioactive molecule are potential immunomodulators against cancer cell metastasis via inactivation of MAPK pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Coriolus versicolor (CV) has been used in traditional Chinese medicine for over 2000 years as a premium medicine for enhancing good health and longevity. The immunomodulatory and anti-cancer effects of polysaccharopeptides (PSP) from cultured CV have been extensively studied; however, the effect and the mechanism of action of other small molecules from CV remain unknown.

AIM OF THE STUDY

we aim to examine the immunomodulatory and anti-cancer effects of the small molecules from CV (SMCV) and identify the active compounds that are responsible for the biological effects against glioblastoma multiforme cells.

MATERIALS AND METHODS

The effects of SMCV/active compound on cytokine and MMP mRNA expressions and productions were assessed by quantitative reverse transcription polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA), respectively. An active compound from SMCV was identified with a bioassay-guided fractionation scheme. The potential mode of action of the active compound was further investigated by identifying the cell signaling pathway. The protein expressions of phospho-ERK, phospho-JNK and phospho-p38 MAPKs were measured by Western Blotting. The anti-invasive effect of SMCV/bioactive compound against T98G, lung carcinoma (A549), and breast adenocarcinoma (MDA-MB-231) cells were determined using invasion assay.

RESULTS

Our results showed that SMCV had strong immunomodulatory effect by suppressing LPS-induced TNF-α production, whereas increasing poly I:C-induced IFN-β level in PBMac. SMCV not only possessed indirect anti-cancer effect by suppressing TNF-α-induced MMP-3 production in glioblastoma T98G cells, but also directly reduced the invasion ability of malignant cells including T98G, A549 and MDA-MB-231. Using bioassay-guided fractionation scheme, we isolated 9-KODE methyl ester (compound AM) that was responsible for the bioactivity of SMCV. This compound suppressed TNF-α-induced MMP-3 production in T98G cells and the suppression may be correlated with the inactivation of p38 mitogen-activated protein kinase (MAPK) pathway. Moreover, compound AM also directly reduced T98G cell invasion.

CONCLUSION

Results of our present study provides scientific evidence that SMCV possesses immunomodulatory and anti-cancer effects. Its bioactive compound, compound AM, is a potential new drug candidate against the invasion and metastasis of glioblastoma cells.

Mechanism of pyroptosis in neurodegenerative diseases and its therapeutic potential by traditional Chinese medicine

Neurodegenerative diseases (NDs) are disorders characterized by degenerative degeneration of neurons and loss of their function. NDs have a complicated pathophysiology, of which neuroinflammation and neuronal death are significant factors. The inflammatory process known as pyroptosis ("fiery death") is caused by a family of pore-forming proteins called Gasdermins (GSDMs), which appears downstream from the activation of the inflammasome. Clear evidence of enhanced pyroptosis-related proteins activity in common NDs has coincided with abnormal aggregation of pathological proteins (such as Aβ, tau, α-synuclein et al.), making pyroptosis an attractive direction for the recent study of NDs. The purpose of this review is to provide an overview of the molecular mechanisms driving pyroptosis, the mechanistic links between pyroptosis and NDs, and emerging therapeutic strategies in Traditional Chinese Medicine (TCM) to inhibit pyroptosis for the treatment of NDs.

Impact of Diet and Lifestyle on Vaccine Efficacy in Adults Aged 55 and Older: A Review

Context

Age-related declines in immune system function, including vaccine responsiveness, are well established. Dietary and lifestyle factors have been investigated in human clinical trials and observational studies for their effects on vaccine response.

Objective

The review intended to assess dietary and lifestyle factors that can modulate vaccine response in a population aged 55 years or older or in a population with an average age of 55 years or older.

Design

The research team performed a narrative review of studies occurring up until May 2021 by searching electronic PubMed databases.

Results

The review findings suggest that two factors may have clinically relevant effects on vaccine response: regular aerobic exercise and psychological environmental stressors, in particular caregiving stress, which studies have consistently found can have a positive and negative effect or association, respectively. In addition, micronutrients used in combination as well as microbiome-targeted interventions show mostly promising results. Other factors may yet be relevant but very few studies have been done.

Conclusions

Heterogeneity of study design, small sample sizes, and other challenges mean that strong conclusions remain elusive. Further study is needed as well as improvements in study design. However, there are indications that certain dietary and lifestyle factors influence vaccine effectiveness.

Astragalus Polysaccharides/PVA Nanofiber Membranes Containing Astragaloside IV-Loaded Liposomes and Their Potential Use for Wound Healing

Delayed wound healing is a common and serious complication in diabetic patients, especially the slow healing of foot ulcers, which seriously affects the quality of life of patients and is also the most important risk factor for lower limb amputation. The multifunctional novel dressing prepared by loading the polymer nanofibers with anti-inflammatory and prohealing plant extracts can promote the wound repair of these ulcers by electrospinning technology. Liposomes are nanoparticles prepared from phospholipids and have been widely used as drug delivery systems. Liposomes can be combined with electrospun nanofibrous webs to facilitate local and sustained delivery of loaded bioactive substances. In this study, liposomes were prepared with astragaloside IV (AS) by employing a modified ethanol injection method and conducting the physical and chemical characterization (e.g., the particle size, polydispersity index, zeta potential, and entrapment efficiency). Astragalus polysaccharides were extracted from Astragalus membranaceus. Subsequently, we prepared the electrospun polyvinyl alcohol (PVA)/astragalus polysaccharide (APS)/astragaloside IV (AS) nanofibers. The morphology of the produced ASL/APS/PVA, APS/PVA, and PVA nanofibers were analyzed by scanning electron microscopy (SEM), and it turns out that the addition of astragalus extract made the fiber diameter smaller and the fibers arranged neatly with no dripping. An induced diabetic rat model was built, and a diabetic ulcer model was built by total cortical resection to assess the prorepair ability of the prepared nanofibers. According to in vivo animal experiments, the nanofibrous membrane loaded with APS and ASL was reported to inhibit the occurrence of wound inflammation, enhance the deposition of collagen fibers (P < 0.05) and the repair of regenerated epithelium (P < 0.05), and effectively strengthen the wound healing of diabetic rats (P < 0.05). In brief, PVA-loaded APS/ASL nanofibrous membranes refer to a prominent wound healing dressing material, which can effectively facilitate the healing of diabetic wounds, and they are demonstrated to be highly promising for application in diabetic wound dressings and tissue engineering.

Phase I Trial of Oral Yeast-Derived β-Glucan to Enhance Anti-GD2 Immunotherapy of Resistant High-Risk Neuroblastoma

Beta glucans, complex polysaccharides, prime leukocyte dectin-1 and CR3-receptors and enhance anti-tumor cytotoxicity of complement-activating monoclonal antibodies. We conducted a phase I study (clinicaltrials.gov NCT00492167) to determine the safety of the combination of yeast-derived beta glucan (BG) and anti-GD2 murine monoclonal antibody 3F8 in patients with relapsed or refractory high-risk neuroblastoma. Patients received intravenous 3F8 (fixed dose of 10 mg/m²/day × 10 days) and oral BG (dose-escalated from 10-200 mg/kg/day × 17 days in cohorts of 3-6 patients each). Forty-four patients completed 141 cycles. One patient developed DLT: transient self-limiting hepatic transaminase elevation 5 days after starting BG (120 mg/kg/day). Overall, 1, 3, 12 and 24 evaluable patients had complete response, partial response, stable and progressive disease, respectively, at the end of treatment. Positive human anti-mouse antibody response and dectin-1 rs3901533 polymorphism were associated with better overall survival. BG dose level and serum BG levels did not correlate with response. Progression-free and overall survival at 2 years were 28% and 61%, respectively. BG lacked major toxicity. Treatment with 3F8 plus BG was associated with anti-neuroblastoma responses in patients with resistant disease. Although the maximal tolerated dose for yeast BG was not reached, considering the large volume of oral BG, we recommended 40 mg/kg/day as the phase II dose.

Medicinal Plants and Mushrooms with Immunomodulatory and Anticancer Properties-A Review on Hong Kong's Experience

The immune modulating effects of selected herbs deserve careful studies to gain evidence-based support for their further development. We have been working hard on many items of medicinal herbs to gain insight into their immunomodulatory effects relevant to cancer treatment in particular, while infection control is not excluded. Nine of them have been selected to give the results of our exploration on their biological, particularly immunomodulatory activities. Since Hong Kong people especially favor one medicinal mushroom, viz. Coriolus versicolor, a number of clinical trials using Coriolus for cancer-related studies are included in this review. While immune modulation platforms are being built for relevant studies, a brief account on the research targets and related procedures are given.

Bombyx batryticatus Protein-Rich Extract Induces Maturation of Dendritic Cells and Th1 Polarization: A Potential Immunological Adjuvant for Cancer Vaccine

Bombyx batryticatus, a protein-rich edible insect, is widely used as a traditional medicine in China. Several pharmacological studies have reported the anticancer activity of B. batryticatus extracts; however, the capacity of B. batryticatus extracts as immune potentiators for increasing the efficacy of cancer immunotherapy is still unverified. In the present study, we investigated the immunomodulatory role of B. batryticatus protein-rich extract (BBPE) in bone marrow-derived dendritic cells (BMDCs) and DC vaccine-immunized mice. BBPE-treated BMDCs displayed characteristics of mature immune status, including high expression of surface molecules (CD80, CD86, major histocompatibility complex (MHC)-I, and MHC-II), increased production of proinflammatory cytokines (tumor necrosis factor-α and interleukin-12p70), enhanced antigen-presenting ability, and reduced endocytosis. BBPE-treated BMDCs promoted naive CD4⁺ and CD8⁺ T-cell proliferation and activation. Furthermore, BBPE/ovalbumin (OVA)-pulsed DC-immunized mice showed a stronger OVA-specific multifunctional T-cell response in CD4⁺ and CD8⁺ T cells and a stronger Th1 antibody response than mice receiving differently treated DCs, which showed the enhanced protective effect against tumor growth in E.G7 tumor-bearing mice. Our data demonstrate that BBPE can be a novel immune potentiator for a DC-based vaccine in anticancer therapy.

Characterization of guava (Psidium guajava Linn) seed polysaccharides with an immunomodulatory activity

To clarify the property of a novel guava seed polysaccharide (GSPS), GSPS was subjected to purify using Sepharose 6B gel filtration chromatography and further characterize the property of each individual isolated fraction. GSPS further resolved into three purified fractions, guava seed polysaccharide fraction 1 (GSF1), GSF2 and GSF3. Isolated GSF1, GSF2 and GSF3 were respectively subjected to high performance size exclusion chromatography; molecular weights of three polysaccharide fractions were determined. GSPS, GSF1, GSF2 and GSF3 were suggested to be proteopolysaccharides or glycoproteins. GSPS, GSF1, GSF2 and GSF3, particularly GSF3, were found to have a Th2-inclination property and anti-inflammatory potential. Heated GSF3 did not significantly (P > .05) decreased its immunomodulatory activity, suggesting that GSF3 is a proteopolysaccharide. The deproteinated GSF3 markedly lost its immunomodulatory activity, suggesting that both protein and carbohydrate moiety in GSF3 are essential to its immunomodulatory function. Analyses of monosaccharides composition in GSF3 using a pre-column derivatization high performance liquid chromatography exhibited that GSF3 was composed of glucuronic acid (3.28%), galacturonic acid (28.13%), galactose (14.88%), mannose (3.96%), glucose (22.99%), arabinose (7.31%), ribose (1.55%), xylose (14.81%), fucose (1.68%) and rhamnose (1.43%). Overall, we evidence that GSF3 is a low molecular weight proteopolysaccharide with potent anti-inflammatory and immunomodulatory effects.

Anti-Aging Implications of Astragalus Membranaceus (Huangqi): A Well-Known Chinese Tonic

Owing to a dramatic increase in average life expectancy and the Family Planning program of the 1970s - 1990s, China is rapidly becoming an aging society. Therefore, the investigation of healthspan-extending drugs becomes more urgent. Astragalus membranaceus (Huangqi) is a major medicinal herb that has been commonly used in many herbal formulations in the practice of traditional Chinese medicine (TCM) to treat a wide variety of diseases and body disorders, or marketed as life-prolonging extracts for human use in China, for more than 2000 years. The major components of Astragalus membranaceus are polysaccharides, flavonoids, and saponins. Pharmacological research indicates that the extract component of Astragalus membranaceus can increase telomerase activity, and has antioxidant, anti-inflammatory, immunoregulatory, anticancer, hypolipidemic, antihyperglycemic, hepatoprotective, expectorant, and diuretic effects. A proprietary extract of the dried root of Astragalus membranaceus, called TA-65, was associated with a significant age-reversal effect in the immune system. Our review focuses on the function and the underlying mechanisms of Astragalus membranaceus in lifespan extension, anti-vascular aging, anti-brain aging, and anti-cancer effects, based on experimental and clinical studies.

Immune responses induced in rabbits after oral administration of bovine serum albumin in combination with different adjuvants (herb extracts, aluminium hydroxide and platinum nanoparticles)

<p>The aim of the current study was to evaluate the immunostimulatory activity of 10 different herbal extracts from <em>Vitex agnus-castus</em>, <em>Vinca major, Aloe arborescens </em>and the polyherbal product containing extracts from <em>Sambucus nigra</em>, <em>Primula</em><em> versis</em>, <em>Pinus alba</em>, <em>Gentiana lutea</em>, <em>Cetraria islandica</em>, <em>Eucaliptus globulus</em>, <em>Citrus limon </em>and aluminium hydroxide, as well as platinum nanoparticles. Rabbits were immunized three times orally with bovine serum albumin (BSA) in combination with the components mentioned above. BSA-specific IgA antibodies in saliva and IgG antibodies in serum were examined by ELISA. It was found that the rabbits immunized with BSA in combination with either platinum nanoparticles or aluminium hydroxide had higher titres of BSA-specific IgA antibodies in their saliva at day 56 of observation. Likewise, rabbits treated with BSA and <em>Vinca major </em>or <em>Aloe arborescens </em>extracts showed higher levels of BSA-specific IgG antibodies in the serum at the end of observation. These results suggest that some plant extracts, aluminium hydroxide and platinum nanoparticles components could be used as oral adjuvants or as immunomodulators for rabbits.</p>

Evaluation of Selected Immunomodulatory Glycoproteins as an Adjunct to Cancer Immunotherapy

Polysaccharopeptide (PSP), from Coriolus versicolor, has been used widely as an adjuvant to chemotherapy with demonstrated anti-tumor and broad immunomodulating effects. While PSP’s mechanism of action still remains unknown, its enhanced immunomodulatory potential with acacia gum is of great interest. Acacia gum, which also contains polysaccharides and glycoproteins, has been demonstrated to be immunopotentiating. To elucidate whether PSP directly activates T-cell-dependent B-cell responses in vivo, we used a well-established hapten carrier system (Nitrophenyl-chicken gamma globulin (NP-CGG)). 6-week C57BL/6 male mice were immunised with 50 μg of NP₂₅-CGG alum precipitate intraperitoneally. Mice were gavaged daily with 50mg/kg PSP in a vehicle containing acacia gum and sacrificed at days 0, 4, 7, 10, 14 and 21. ELISA was used to measure the total and relative hapten-specific anti-NP IgA, IgM and IgG titre levels compared to the controls. It was found that PSP, combined with acacia gum, significantly increased total IgG titre levels at day 4 (P< 0.05), decreased IgM titre levels at days 4 and 21 (P< 0.05) with no alterations observed in the IgA or IgE titre levels at any of the time points measured. Our results suggest that while PSP combined with acacia gum appears to exert weak immunological effects through specific T-cell dependent B-cell responses, they are likely to be broad and non-specific which supports the current literature on PSP. We report for the first time the application of a well-established hapten-carrier system that can be used to characterise and delineate specific T-cell dependent B-cell responses of potential immunomodulatory glycoprotein-based herbal medicines combinations in vivo.

In vitro and in vivo studies of the immunomodulatory effect of Echinacea purpurea on dendritic cells

BACKGROUND

Extracts of Echinacea have been used traditionally for the treatment of diverse types of infections and wounds. They have become very familiar immunostimulant herbal medicine. However, the specific immunomodulatory effect of Echinacea remains to be elucidated.

AIM

In our study, the effect of Echinacea purpurea extract on the generation of immature DCs from monocytes was described, as well as its effect on DC differentiation. In addition, an in vivo experiment was conducted to investigate whether treatment of mice with extracts derived from E. purpurea has immunomodulatory effect on murine splenic DCs.

METHODS

Immature DCs were generated by incubating peripheral blood monocytes with cytokine cocktail (GM-CSF + IL-4) and matured by tumor necrosis factor-α (TNF-α). The cells were randomized to 5 groups to investigate E. purpurea effect in different stages. Phenotypic analysis of cell marker CD83-expressed on DCs was performed by flow cytometry. Mice were randomly divided into 3 groups; control, E. purpurea treated and E. purpurea-TNF-α treated group. The murine splenic DCs were isolated and phenotyped for CD83 and CD11c by flow cytometry.

RESULTS

Treatment of monocytes with E. purpurea prior to addition of the maturation factor TNF-α resulted in a significant decrease in the yield of DC expressing CD83. On the other hand, immature DCs generated in the culture in the presence of GM-CSF and IL-4, when treated simultaneously with E. purpurea and TNF-α, exhibited an insignificant change in the yield of CD83-expressing DCs compared with untreated control. The in vivo experiments showed that splenic DCs obtained from mice treated with E. purpurea with or without TNF-α did not exhibit significant changes in CD83 or CD11c compared with those obtained from control mice.

CONCLUSION

Our findings suggest that the immunomodulatory mechanisms of E. purpurea impact generation fate of DCs rather than differentiation stages. The results obtained in the in vivo study utilizing murine splenic DCs supported those observed in vitro.

Astragulus polysaccharide-loaded fibrous mats promote the restoration of microcirculation in/around skin wounds to accelerate wound healing in a diabetic rat model

Tissue engineering scaffolds (TES) can carry numerous biomacromolecules and cells, and they have been widely used in diabetic skin wound healing with positive effects. However, the bioactive retention of biomacromolecules and cells during fabrication and storage is still a factor restricting their use. Moreover, impaired blood supply in/around poorly healing diabetic skin wounds has not been considered. In the present study, a bioactive natural substance of Astragalus polysaccharide (APS), which has stable and confirmed effects on endothelial protection, was embedded into fibrous TES by electrospinning. The administration of APS-loaded TES on the skin wound in a diabetic rat model led to a dose-dependent promotion in skin blood flow around wounds and an increase in endoglin expression and microvessel density in regenerated skin tissues. Furthermore, the higher loading of APS in TES led to faster collagen synthesis, appendage and epidermal differentiation, and wound closure. In summary, the combination of APS with TES is a potentially novel therapeutic strategy for diabetic skin wound healing, as it not only mimics the ultrastructure of extracellular matrixes but also restores skin microcirculation.

Traditional Chinese medicine and cancer: History, present situation, and development

Cancer treatment with traditional Chinese medicine (TCM) has a long history. Heritage provides general conditions for the innovation and development of TCM in oncology. This article reviews the development of TCM in oncology, interprets the position and function of TCM for cancer prevention and treatment, summarizes the innovations of TCM in oncology over nearly fifty years, and suggests the development direction.

A novel immunomodulatory hemocyanin from the limpet Fissurella latimarginata promotes potent anti-tumor activity in melanoma

Hemocyanins, the huge oxygen-transporting glycoproteins of some mollusks, are used as immunomodulatory proteins with proven anti-cancer properties. The biodiversity of hemocyanins has promoted interest in identifying new anti-cancer candidates with improved immunological properties. Hemocyanins promote Th1 responses without known side effects, which make them ideal for long-term sustained treatment of cancer. In this study, we evaluated a novel hemocyanin from the limpet/gastropod Fissurella latimarginata (FLH). This protein has the typical hollow, cylindrical structure of other known hemocyanins, such as the keyhole limpet hemocyanin (KLH) and the Concholepas hemocyanin (CCH). FLH, like the KLH isoforms, is composed of a single type of polypeptide with exposed N- and O-linked oligosaccharides. However, its immunogenicity was significantly greater than that of KLH and CCH, as FLH induced a stronger humoral immune response and had more potent anti-tumor activity, delaying tumor growth and increasing the survival of mice challenged with B16F10 melanoma cells, in prophylactic and therapeutic settings. Additionally, FLH-treated mice demonstrated increased IFN-γ production and higher numbers of tumor-infiltrating CD4⁺ lymphocytes. Furthermore, in vitro assays demonstrated that FLH, but not CCH or KLH, stimulated the rapid production of pro-inflammatory cytokines (IL-6, IL-12, IL-23 and TNF-α) by dendritic cells, triggering a pro-inflammatory milieu that may explain its enhanced immunological activity. Moreover, this effect was abolished when deglycosylated FLH was used, suggesting that carbohydrates play a crucial role in the innate immune recognition of this protein. Altogether, our data demonstrate that FLH possesses increased anti-tumor activity in part because it activates a more potent innate immune response in comparison to other known hemocyanins. In conclusion, FLH is a potential new marine adjuvant for immunization and possible cancer immunotherapy.

Immunomodulatory and therapeutic potentials of herbal, traditional/indigenous and ethnoveterinary medicines

Herbs/Botanical plants are considered as God's gift to human beings in the form of natural medicines, like the one well known "Sanjeevani booti" described in Hindu Mythology. The traditional and ethno-veterinary practices have been in use for centuries, transferring the knowledge from generation to generation and they are accessible, easy to prepare and administer, with little or no cost at all. Even though the modern developments in therapeutic field brought about a rapid decline in traditional medicine, the plant-based remedies are still having a crucial role as potential source of therapeutic aids in health systems all over the world for both humans and animals. Among the 21,000 medicinal plants listed by the World Health Organization (WHO), 2500 species are native to India, which stands first in the production of medicinal herbs. This innumerable treasure of medicinal herbs brings India the distinction of 'the botanical garden of the world'. Nowadays immune-based therapies are gaining more importance than monovalent approaches which are having limited benefits. Apart from the actions like treating diseases, control of ecto- and endo-parasites, fertility enhancement, bone setting and poor mothering management, an array of herbal medicines have been reported which are having immunomodulatory effects like modulation of cytokine secretion, histamine release, immunoglobulin secretion, class switching, cellular co-receptor expression, lymphocyte expression, phagocytosis and so on. The present article describes in brief few of these important ones viz., ashwagandha, amla, tulsi, arjuna, aloe vera, garlic, turmeric, ginger, shatavari, neem, guduchi, kiwifruit, tut, kamala, palashlata, kokilaksha etc. being used for human and animal health benefits.

Protein-bound polysaccharide activates dendritic cells and enhances OVA-specific T cell response as vaccine adjuvant

Protein-bound polysaccharide-K (PSK) is a hot water extract from Trametes versicolor mushroom. It has been used traditionally in Asian countries for its immune stimulating and anti-cancer effects. We have recently found that PSK can activate Toll-like receptor 2 (TLR2). TLR2 is highly expressed on dendritic cells (DC), so the current study was undertaken to evaluate the effect of PSK on DC activation and the potential of using PSK as a vaccine adjuvant. In vitro experiments using mouse bone marrow-derived DC (BMDC) demonstrated that PSK induces DC maturation as shown by dose-dependent increase in the expression of CD80, CD86, MHCII, and CD40. PSK also induces the production of multiple inflammatory cytokines by DC, including IL-12, TNF-α, and IL-6, at both mRNA and protein levels. In vivo experiments using PSK as an adjuvant to OVAp323-339 vaccine showed that PSK as adjuvant leads to enlarged draining lymph nodes with higher number of activated DC. PSK also stimulates proliferation of OVA-specific T cells, and induces T cells that produce multiple cytokines, IFN-γ, IL-2, and TNF-α. Altogether, these results demonstrate the ability of PSK to activate DC in vitro and in vivo and the potential of using PSK as a novel vaccine adjuvant.

Macrophage activating activity of pyrrole alkaloids from Morus alba fruits

ETHNOPHARMACOLOGICAL RELEVANCE

The fruits of Morus alba have been traditionally used as a tonic to enhance immune responses.

MATERIALS AND METHODS

The macrophage activating constituents of Morus alba fruits were purified using various column chromatography techniques. The structures of isolated compounds were determined on the basis of spectroscopic data interpretation such as 1D and 2D NMR analysis. The macrophage activating activities of isolated compounds were evaluated by measuring the production of nitric oxide, TNF-α and IL-12 in RAW 264.7 cells. The phagocytic activity was also evaluated.

RESULTS

Five pyrrole alkaloids, 5-(hydroxymethyl)-1H-pyrrole-2-carboxaldehyde (1), 2-formyl-1H-pyrrole-1-butanoic acid (2), 2-formyl-5-(hydroxymethyl)-1H-pyrrole-1-butanoic acid (3), 2-formyl-5-(methoxymethyl)-1H-pyrrole-1-butanoic acid (4) and Morrole A (5) were isolated from the fruits of Morus alba. Morrole A (5) is first reported in nature and other pyrrole alkaloids (1-4) are first reported from Morus species. Among the isolated compounds, compounds 3 and 4 significantly activated macrophage activity by the enhancement of nitric oxide, TNF-α and IL-12 production, and the stimulation of phagocytic activity in RAW 264.7 cells.

CONCLUSION

Pyrrole alkaloids, including a new compound, were isolated from Morus alba fruits. These compounds activated macrophage activity in RAW 264.7 cells.

Enhancement of the immunogenicity and protective efficacy of a mucosal influenza subunit vaccine by the saponin adjuvant GPI-0100

Identification of safe and effective adjuvants remains an urgent need for the development of inactivated influenza vaccines for mucosal administration. Here, we used a murine challenge model to evaluate the adjuvant activity of GPI-0100, a saponin-derived adjuvant, on influenza subunit vaccine administered via the intranasal or the intrapulmonary route. Balb/c mice were immunized with 1 µg A/PR/8 (H1N1) subunit antigen alone or in combination with varying doses of GPI-0100. The addition of GPI-0100 was required for induction of mucosal and systemic antibody responses to intranasally administered influenza vaccine and significantly enhanced the immunogenicity of vaccine administered via the intrapulmonary route. Remarkably, GPI-0100-adjuvanted influenza vaccine given at a low dose of 2×1 µg either in the nares or directly into the lungs provided complete protection against homologous influenza virus infection.

Effects of topical application of Astragalus membranaceus on allergic dermatitis

Astragalus membranaceus (AM) is one of the most popular health-promoting herbs in East Asia, and has been used in traditional medicine for more than 2000 years. This study was performed to examine whether AM suppresses atopic dermatitis (AD)-like skin lesions in BALB/c mice. Seven-week-old female BALB/c mice were sensitized with 1-chloro-2,4-dinitrobenzene (DNCB) to induce allergic dermatitis. Skin sections were stained with hematoxylin and eosin (H&E) to assess epidermal and dermal hyperplasia, which were determined by measuring the thicknesses of the epidermis and dermis, respectively. The serum immunoglobulin G (IgE) concentration was quantified by enzyme-linked immunosorbent assay (ELISA). In addition, the levels of interleukins (IL)-4, -5, -6, and -13 and tissue necrosis factor (TNF)-α were measured in mouse serum. Significance was determined by one-way analysis of variance (ANOVA). Topical AM markedly improved the AD skin lesions in DNCB-induced mice. The AD skin lesions were significantly thinner in the AM treatment group compared with untreated controls, and the hyperkeratosis disappeared. Topical treatment of AM also restored nuclear factor-κB (NF-κB) expression. In addition, the serum IgE level was reduced. AM suppressed the expression of Th2 cytokines (IL-4, -5, -6, and -13) and significantly decreased the TNF-α level. AM is effective for treating AD by regulating cytokines. AM may be an alternative or complementary therapeutic option for treating patients with AD. More in-depth studies are necessary to clarify the mechanisms of AM.

Astragalus polysaccharides enhance immune responses of HBV DNA vaccination via promoting the dendritic cell maturation and suppressing Treg frequency in mice

Astragalus polysaccharides (APS), an extract from a kind of Chinese traditional herb Astragalus membranaceus, was proved to have strong immunoregulatory properties. In this study, APS was employed as an adjuvant of Hepatitis B virus (HBV) DNA vaccine (pcDS2) and its' effects on immune system of mice were investigated. Our data demonstrated that APS as an adjuvant could increase the HBsAg-specific antibody level as well as the proliferating activity of T cells. APS also could induce CD4(+) T cells to produce IL-4, IL-2 and IFN-γ and enhance IFN-γ expression of CD8(+) T cells. Moreover, APS could induce the robust activity of the cytotoxic lymphocytes (CTL). Additionally, APS could stimulate the dendritic cells (DC) maturation which is characterized by up-regulation of MHC I/II, CD40, CD80 and CD86, and decreased the frequency of the regulatory T cells (nTreg). Collectively, these findings suggest that APS is a potent adjuvant for the hepatitis B DNA vaccine and can enhance the immune responses of HBV DNA vaccine via promoting DC maturation and inhibit the Treg frequency.

QSAR, docking and in vivo studies for immunomodulatory activity of isolated triterpenoids from Eucalyptus tereticornis and Gentiana kurroo

Two triterpenoids ursolic acid (1) and lupeol (2) isolated and characterized from Eucalyptus tereticornis and Gentiana kurroo were subjected to in silico QSAR modeling and docking studies and later the predicted results were confirmed through in vivo experiments. QSAR modeling results showed that both the triterpenoids possess immunomodulatory and anti-inflammatory activity comparable to boswellic and cichoric acids, but were less active than levamisol. Docking results suggested that both the triterpenoids (1 and 2) showed immune modulatory and anti-inflammatory activity due to high binding affinity to human receptors viz., NF-kappaB p52 (-50.549 kcal/mol), tumor necrosis factor (TNF-alpha) (-47.632 kcal/mol), nuclear factor NF-Kappa-B P50 (-16.798 kcal/mol) and cyclooxygenase-2 (-55.244 kcal/mol). Further both the triterpenoids (1 and 2) were subjected to in vivo immunomodulatory activity in female Swiss albino mice. The experimental mice were divided into nine groups, each comprised of six mice. These received oral treatment for a period of 28 days. The triterpenoids (1 and 2) showed significant increased in humoral immune function, but no significant changes were observed in cell mediated immune response and hematological parameters. The in silico and in vivo experimental data suggested that both the triterpenoids 1 and 2 may be considered as potential immunomodulatory drug-like molecules.

Astragalus polysaccharides enhance the humoral and cellular immune responses of hepatitis B surface antigen vaccination through inhibiting the expression of transforming growth factor β and the frequency of regulatory T cells

Astragalus polysaccharides (APS), extracted from the root of Astragalus membranaceus, a traditional Chinese medicinal herb, have extensive pharmacological and strong immunomodulatory effects. In this study, the potential adjuvant effect of APS on humoral and cellular immune responses to hepatitis B subunit vaccine was investigated. Coadministration of APS with recombinant hepatitis B surface antigen significantly increased antigen-specific antibody production, T-cell proliferation and CTL (cytotoxic T lymphocyte) activity. Production of interferon-γ (IFN-γ), interleukin-2 (IL-2) and IL-4 in CD4(+) T cells and of IFN-γ in CD8(+) T cells were dramatically increased. Furthermore, expression of the genes PFP, GraB, Fas L and Fas were up-regulated; interestingly, expression of transforming growth factor β (TGF-β) and the frequency of CD4(+)CD25(+)Foxp3(+) regulatory T cells (Treg cells) were down-regulated. Expression of Toll-like receptor 4 (TLR4) was significantly increased by administration of APS. Together, these results suggest that APS is a potent adjuvant for the hepatitis B subunit vaccine and can enhance both humoral and cellular immune responses via activating the TLR4 signaling pathway and inhibit the expression of TGF-β and frequency of Treg cells.

Plant immunostimulants--scientific paradigm or myth?

In traditional medicine, numerous plant preparations are used to treat inflammation both topically and systemically. Several anti-inflammatory plant extracts and a few natural product-based monosubstances have even found their way into the clinic. Unfortunately, a number of plant secondary metabolites have been shown to trigger detrimental pro-allergic immune reactions and are therefore considered to be toxic. In the phytotherapy research literature, numerous plants are also claimed to exert immunostimulatory effects. However, while the concepts of plant-derived anti-inflammatory agents and allergens are well established, the widespread notion of immunostimulatory plant natural products and their potential therapeutic use is rather obscure, often with the idea that the product is some sort of "tonic" for the immune system without actually specifying the mechanisms. In this commentary it is argued that the paradigm of oral plant immunostimulants lacks clinical evidence and may therefore be a myth, which has originated primarily from in vitro studies with plant extracts. The fact that no conclusive data on orally administered immunostimulants can be found in the scientific literature inevitably prompts us to challenge this paradigm.

The known immunologically active components of Astragalus account for only a small proportion of the immunological adjuvant activity when combined with conjugate vaccines

The 95 % ethanol extract of Astragalus has been demonstrated to have potent activity as an immunological adjuvant when administered with vaccines of various types. We endeavor here to identify the components of this extract that are responsible for this adjuvant activity. Mice were immunized with KLH conjugated to cancer carbohydrate antigens globo H and GD3 and cancer peptide antigen MUC1 combined with different Astragalus fractions or with commercially available Astragalus saponins and flavonoids. The antibody responses against cancer antigens and KLH were quantitated in ELISA assays, and toxicity was calculated by weight loss. Astragalosides II and IV were the most active components, but the toxicity of these two differed dramatically. Astragaloside II was the most toxic Astragalus component with 5-10 % weight loss at a dose of 500 µg while astragaloside IV showed no weight loss at all at this dose, suggesting that astragaloside IV might be utilized as an immunological adjuvant in future studies. Several flavonoids also had significant adjuvant activity. However, when the activities of these known immunologically active components of Astragalus (and of endotoxin) are calculated based on the extent of their presence in the 95 % ethanol extract, they provide only a small proportion of the immunological activity. This raises the possibility that additional uniquely active components of Astragalus may contribute to adjuvant activity, or that the adjuvant activity of Astragalus is greater than the activity of the sum of its parts.

Adjuvant effects of Astragalus saponins macrophyllosaponin B and astragaloside VII

AIM OF THE STUDY

The present study was undertaken to evaluate the hemolytic activities of two immunomodulator Astragalus saponins [Macrophyllosaponin B (MacB) from Astragalus oleifolius DC. and Astragaloside VII (Ast VII) from Astragalus trojanus Stev.], and their adjuvant potentials on the cellular and humoral immune responses of Swiss albino mice against BSA.

MATERIALS AND METHODS

The hemolytic activity of Mac B and Ast VII was determined using 0.5% rabbit red blood cell. For adjuvant activity, Swiss albino mice were immunized subcutaneously with BSA 100 μg alone or with BSA 100 μg dissolved in saline containing Ast VII (30, 60, 120 and 240 μg), Mac B (30, 60, 90 and 120 μg) or Freund's adjuvant on Days 1 and 15. Sera and splenocytes were collected 2 weeks after the last immunization for concanavalin A (Con A)-, lipopolysaccharide (LPS)- and BSA-stimulated splenocyte proliferation assay and measurement of BSA-specific antibodies in serum.

RESULTS

Mac B and Ast VII showed a slight hemolytic effect, with 0.42% and 0.54% values, respectively, at the highest concentration of 500 μg/ml. Mac B and Ast VII significantly enhanced the Con A-, LPS-, and BSA-induced splenocyte proliferation in the BSA-immunized mice especially at 120 and 240 μg (P<0.001), and 60, 90 and 120 μg (P<0.05, P<0.01 or P<0.001) doses, respectively. BSA-specific IgG, IgG1 and IgG2b antibody titers in serum were also significantly enhanced by Ast VII (120 μg), Mac B (90 μg) and Freund's as compared to the control group (P<0.01 or P<0.001). Moreover, the IFN-γ and IL-4 levels in the sera were detected using ELISA two weeks after the last immunization. Ast VII and Mac B were also found to stimulate IFN-γ production such as Freund's, two weeks after the last immunization at doses of 120 μg and 90 μg, respectively, as compared to the control.

CONCLUSION

Results show that Ast VII and Mac B generate important specific antibody and cellular response against BSA in mice, proving their potentials as a new class saponin adjuvant.

Human dendritic cells activated via dectin-1 are efficient at priming Th17, cytotoxic CD8 T and B cell responses

Background

Dendritic cells capture antigens through PRRs and modulate adaptive immune responses. The type of adaptive immune T cell response generated is dependent upon the type of PRR activated by the microbes. Dectin-1 is a C-type lectin receptor present on dendritic cells.

Methodology/Principal Findings

Here we show that selective dectin-1 agonist Curdlan can activate human DCs and induce the secretion of large amounts of IL-23, IL-1β, IL-6 and low levels of IL-12p70 as determined by ELISA. The Curdlan-stimulated DCs are efficient at priming naïve CD4 cells to differentiate into Th17 and Th1 cells. Furthermore, these CD4 T cells induce differentiation of B cells to secrete IgG and IgA. In addition, Curdlan-stimulated DCs promote the expansion and differentiation of Granzyme and perforin expressing cytotoxic T lymphocyte that display high cytolytic activity against target tumor cells in vitro.

Conclusions/Significance

These data demonstrate that DCs stimulated through Dectin-1 can generate efficient Th, CTL and B cell responses and can therefore be used as effective mucosal and systemic adjuvants in humans.

Regulation of inflammatory gene expression in PBMCs by immunostimulatory botanicals

Many hundreds of botanicals are used in complementary and alternative medicine for therapeutic use as antimicrobials and immune stimulators. While there exists many centuries of anecdotal evidence and few clinical studies on the activity and efficacy of these botanicals, limited scientific evidence exists on the ability of these botanicals to modulate the immune and inflammatory responses. Using botanogenomics (or herbogenomics), this study provides novel insight into inflammatory genes which are induced in peripheral blood mononuclear cells following treatment with immunomodulatory botanical extracts. These results may suggest putative genes involved in the physiological responses thought to occur following administration of these botanical extracts. Using extracts from immunostimulatory herbs (Astragalus membranaceus, Sambucus cerulea, Andrographis paniculata) and an immunosuppressive herb (Urtica dioica), the data presented supports previous cytokine studies on these herbs as well as identifying additional genes which may be involved in immune cell activation and migration and various inflammatory responses, including wound healing, angiogenesis, and blood pressure modulation. Additionally, we report the presence of lipopolysaccharide in medicinally prepared extracts of these herbs which is theorized to be a natural and active component of the immunostimulatory herbal extracts. The data presented provides a more extensive picture on how these herbs may be mediating their biological effects on the immune and inflammatory responses.

Echinacea purpurea aerial extract alters course of influenza infection in mice

Influenza infection is a major clinical problem and Echinacea purpurea, a widely consumed botanical product, is purported to alter the course of respiratory infections including influenza. Mice infected with WSN influenza A and treated with E. purpurea polysaccharide extract had less weight loss than untreated mice but similar pulmonary viral titers. Echinacea-treated mice had lower systemic and pulmonary KC and IL-10 levels and lower systemic IFN-gamma levels following influenza infection. These suggest that E. purpurea alters the clinical course of influenza infection in mice through modulation of cytokines and not direct antiviral activity.

The Public Health Impact of Herbs and Nutritional Supplements

Dietary supplement use has increased exponentially in recent years despite the lack of regulatory oversight and in the face of growing safety concerns. This paper provides an overview of the public health implications and safety concerns associated with dietary supplement use, especially by cancer patients. Botanical research is actively pursued at the Memorial Sloan-Kettering Cancer Center (MSKCC) Integrative Medicine department. Work of the MSKCC Center for the Study of Botanical Immunomodulators is described, and guidelines for cancer patients' use of dietary supplements outlined. Herbs and other botanicals are complex, physiologically active agents, but little is known about most of the popular, widely available dietary supplements. Herb-drug interactions, a major concern, are exacerbated in the cancer setting. Biologically active agents may interfere with chemotherapy and other prescription medications. They may exert anti-coagulant activity at rather inconvenient times such as during surgery, and create other serious problems. Research on the bioavailability, effective dosage, safety and benefits of these complex agents is sorely needed. Oncology professionals and other healthcare providers should educate themselves and their patients about these issues. Probably the largest, continuously-updated free information resource is MSKCC's AboutHerbs website (www.mskcc.org/AboutHerbs).

Supplements for immune enhancement in hematologic malignancies

This brief review aims to discuss the various cellular immunological aspects and related mechanisms of the use of specific components from traditional herbal medicines. We begin with lessons learned from thalidomide as an effective single drug with multiple mechanisms of action to treat multiple myeloma. Examples of “supplements” or integrative therapy will be drawn from arsenic trioxide, medicinal mushrooms including Coriolus vesicular and Ganoderma lucidum, followed by the discussion of beta-glucans affecting various immunological important cellular subsets. Different classes of compounds may enhance distinct immune cell populations that might contribute to a multi-targeted holistic effects on anti-cancer treatment. Finally, we conclude by highlighting an herbal formulation PHY906 as a potential adjunct to chemotherapy that might become one of the first US Food and Drug Administration (FDA) approved oral herbal medicines for anti-cancer adjunct treatment.