Effect of lentinan against immunosuppression of lymphocytes cultured in simulated microgravity environment / 中国实验血液学杂志

This study was aimed to evaluate the effect of lentinan on the immune function of splenic lymphocytes in rotary cell culture system (RCCS) microgravity environment. The splenic lymphocytes from mice were separated and cultured in the normal gravity and the microgravity environments. The cells were treated with lentinan solution (0, 10, 20 and 40 µg/ml). After incubated with lentinan for indicated times (24, 48 and 72 h), the cell proliferation, secretion of cytokine and the expression of cell surface markers were detected by MTT method, ELISA and flow cytometry respectively. The results indicated that lentinan of above mentioned concentrations did not obviously promote the lymphocyte proliferation, but increased the secretion of IL-2 and IFN-γ and enhanced the expression of lymphocyte surface markers CD4 and CD8 in microgravity environment. It is concluded that lentinan has the ability to enhance the lymphocyte immune function in microgravity environment.

Clinical observation of thermotherapy combined with thoracic injection of lentinan in treatment of cancerous hydrothorax of patients with lung cancer / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To study the therapeutic effect and mechanism of thermotherapy combined with thoracic injection of lentinan in treatment of cancerous hydrothorax (CH) in patients with lung cancer.</p><p><b>METHODS</b>Sixty lung cancer patients complicated with CH were randomly assigned to the observation group and the control group, 30 in each. CH was released by closed drainage of the thoracic cavity in all patients. Thermotherapy was given to patients in the observation group after lentinan was thoracically injected, while lentinan was thoracically injected to patients in the control group.</p><p><b>RESULTS</b>The total effective rate of CH improvement was 73.3% (22/30) in the control group and 83.3% (25/30) in the observation group, showing insignificant difference (P>0.05). The stability rate and the weight stability rate by Karnofsky's performance scoring in the observation group were superior to those of the control group, showing significant difference (P<0.05). No hematological reaction, hepatic or renal damage occurred before and after treatment in both groups. Fever, thoracalgia, dyspnea, rash, nausea and vomit appeared in few patients of the two groups, showing insignificant difference (P>0.05). CD3+, CD4+, CD4+/CD8+, and NK obviously increased and CD8+ decreased in the observation group after treatment, showing significant difference from those before treatment (P<0.05). Compared with the control group after treatment, CD3+, CD4+, CD4+/CD8+, and NK obviously increased, CD8+ increased in the observation group (P<0.05).</p><p><b>CONCLUSION</b>Thermotherapy combined with thoracic injection of lentinan showed better effect in treatment of CH in patients with lung cancer. No obvious adverse reaction was seen.</p>

Effects of lentinan on interleukin-1β-induced transdifferentiation of human embryonic lung fibroblasts to myofibroblasts / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To study the effects of interleukin-1β (IL-1β) on transdifferentiation of human embryonic lung fibroblasts to myofibroblasts and the effects of lentinan on the transdifferentiation.</p><p><b>METHODS</b>The human embryonic lung fibroblasts were cultured in vitro, and fibroblasts were treated with different concentrations of IL-1β and lentinan. The proliferation activity of the human embryonic lung fibroblasts was evaluated by the Cell Counting Kit-8 (CCK-8). The expression of α-smooth muscle actin (α-SMA) protein was measured by immunocytochemistry. The levels of fibronectin (FN), typeⅠcollagen (ColⅠ) and α-SMA mRNA were detected by RT-PCR.</p><p><b>RESULTS</b>Compared with the untreated control group, the absorbance value of cell proliferation, α-SMA protein levels, FN, ColⅠand α-SMA mRNA expression were significantly up-regulated after different concentrations of IL-1β (0.1, 1, 10 ng/mL) treatment for 48 hrs (P<0.01). Lentinan treatment inhibited up-regulation of the cell proliferation activity, α-SMA protein levels, FN, ColⅠand α-SMA mRNA expression induced by IL-1β in a dose-independent manner (P<0.01).</p><p><b>CONCLUSIONS</b>Lentinan can suppress human embryonic lung fibroblast proliferation, fibroblast-myofibroblast transdifferentiation and extra cellular matrix synthesis induced by IL-1β.</p>

Lentinan induces the expression of human-beta-defensin-2 in pulmonary epithelial cells / 生物医学工程学杂志

To determine whether lentinan could upregulate the expression of human-beta-defensin-2(HBD-2) in pulmonary epithelial cells (SPC-A-1), we stimulated pulmonary epithelial cells with lentinan and detected the expression of HBD-2mRNA by RT-PCR test. The results demonstrated that the expression of HBD-2mRNA in SPC-A-1 could be induced by lentinan in a concentration and time-dependent manner.

Lentinan-graft-polyethylenimine-a novel vector for gene delivery / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To develop a novel vector for gene delivery with low molecular weight polyethylenimine grafted to the natural polysaccharide and conjugated to folic acid (LNT-PEI-FA).</p><p><b>METHODS</b>The properties of LNT-PEI-FA were characterized by (1)H-NMR, FT-IR and TGA, respectively. The particle size of LNT-PEI-FA/DNA complex was measured. The DNA binding ability of LNT-PEI-FA was detected by gel electrophoresis retardation assay.</p><p><b>RESULT</b>The particle size of LNT-PEI-FA/DNA complex was about 200 nm. Gel electrophoresis showed that at N/P ratio of 1.8 (W/W) the polymer was able to completely condense DNA. In vitro experiments showed a high efficiency of gene transfection in A293 and B16 cell lines.</p><p><b>CONCLUSION</b>A novel non-viral vector LNT-PEI-FA was successfully synthesized and characterized, which may be applied in gene transfection research in the future.</p>

Study on effect of lentinan in enhancing anti-tumor action of dendritic cytoma vaccine and its mechanism / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To improve the anti-tumor effect of dendritic cytoma vaccine (DCV) for finding an effective anti-tumor biotherapy.</p><p><b>METHODS</b>DC vaccine prepared by transfection of adenovirus mediated melanoma-associated antigen gene (gp100) into bone marrow-derived dendritic cell (DC) was used to study the immuno-therapeutic effect and the mechanism of lentinan (LNT) in different dosages, used alone or combined with gp100-DC for treatment of B16 melanoma bearing mice.</p><p><b>RESULTS</b>After being treated with LNT combining gp100-DC, the growth of malignant melanoma was inhibited with the tumor-free survival in the experimental animals being 66.7%. The treatment could also significantly enhance the activity of cytotoxicity T lymphocyte (CTL) and natural killer (NK) cells, elevate the levels of interleukin-2 (IL-2) and interferon-gamma (IFN-gamma) in splenocytes, and histological examination showed that a large amount of inflammatory cells infiltrated inside and around the tumor, and obvious necrosis of tumor cells was found.</p><p><b>CONCLUSION</b>By combined use with LNT the anti-tumor immuno-reaction of DCV vaccine could be enhanced effectively.</p>

Establishment of a transgenic cell model for preliminary screening of chemopreventive agents / 生物工程学报

To develop a GFP transgenic cell model under the transcriptional control of TK promoter adjacent to which ARE enhancer was inserted. Synthetic oligonucleotide ARE motif was annealed and purified then inserted into pTK-GFP to construct the vector of pARE-TK-GFP. The TK and ARE-TK fragments were amplified by PCR and cloned into pEGFP-N1 to reconstruct eukaryotic expression vectors of pTK-GFP/Neo and pARE-TK-GFP/Neo. They were transfected into HepG2 cells and clones resistant G418 were isolated. PDTC and Lentinan were used to induce the cell levels of GFP and the fluorescence was measured using a fluorescence plate reader. The results showed that the induced level of GFP is significantly increased and have dose-dependeny in a certain range. This findings indicated that such a cell model offered a potential platform for preliminary screening of all kinds of natural or synthetic chemopreventive agents.

Comparison between Immunostimulatory Activity and Molecular Structure of Different Polysaccharides

BACKGROUND: We previously reported that ginsan, a polysaccharide extracted from Panax ginseng had an immunostimulatory activity such as mitogenic activity, activation of macrophages and killer cells, and production of a variety of cytokines which resulted in antitumor and antiseptic effects. We further purified alpha-(1-->6)-glucan and beta-(2-->6)-fructan from the ginsan with size exclusion and ion-exchange column chromatography successively. In this study, we performed the structure-based activity of ginsan by comparison with known polysacchrides such as beta-glucan, curdlan, laminarin, levan, dextran, lentinan and OK-432. METHODS: To investigate the immunostimulatory activity of several polysaccharide compounds, we investigated the stimulation of lymphocytes proliferation, the generation of activated killer cells and the secretion of nitrites from activated macrophages. RESULTS: Of polysaccharides tested, curdlan and ginsan stimulated lymphocyte proliferation, suggesting that the molecular weight and composition of polysaccharide are dependent on the mitogenic activity. The production of nitric oxide was significantly increased in curdlan, levan, ginsan and its fraction, indicating that fructan has also capacity to activate macrophages and may devote to kill pathogens. In addition, the activation of macrophages was seemed to be independent of molecular weight of polysaccharide. The generation of AK cells was exhibited in order of curdlan, OK-432> F1, ginsan, F3>levan>etc. The AK activity may be dependent on molecular weight and composition of polysaccharides. CONCLUSION: Unfortunately, purified polysaccharide from ginsan were less active on immunostimulatory activity than mixed compounds of polysaccharides. From the viewpoint of structure and activity relationships, we found several characteristic features.

Characteristics of B Cell proliferation by polysaccharide fraction of Paeonia japonica miyabe

BACKGROUND: Paeonia j ap onica Miyabe is a medicinal plant which has been widely used as a component of blood-building decoctions (Chinese medicinal concept : Bu-Xie). The immunopharmacological characteristics of the extract of Paeonia j ap onica (PJ) were investigated. METHODS: The effects of fractions of PJ extract on lymphocyte proliferation were measured by H3 -thymidine incorporation assay . The proliferated lymphocyte subsets were analyzed in flow cytometry . The subset cell populations of spleen cells were separated by magnetic cell separation system, and their proliferation by the extract were investigated. The effect of the extract on antibody production was determined in mice challenged with sheep red blood cells (SRBC) using hemolytic plaque forming cell assay. RESULTS: Spleen cells were proliferated by water extract of PJ. Polysaccharide fraction (PJ-P) of the extract was most active in the proliferation. It was found in flow cytometry that the lymphocyte subset proliferated by PJ-P was B cell population. Among the separated subset cell populations, T cell-depleted cell population and macrophage-depleted cell population were most proliferated by PJ-P. However, positively selected populations of B cells and T cells were not proliferated by PJ-P. These result s indicate that B cell proliferation by PJ-P may require the assistance of macrophages or T cells. These result s suggest that firstly PJ-P may stimulate macrophages or T cells, and then B cells are activated. The number of antibody-secreting cells was increased by administration of PJ-P in mice immunized with SRBC as a T-dependent antigen. CONCLUSION: These result s suggest that macrophages and accessory cells are directly activated by PJ-P and then helper T cells and B cells are indirectly activated. As the results, immune responses might be coordinately improved. In conclusion, PJ-P, a polysaccharide of P. j ap onica, may be a characteristic immunostimulator, which is analogous to polysaccharides such as lentinan, PSK and ginsan.