Effect of Maitake (Grifola frondosa) D-Fraction on the Activation of NK Cells in Cancer Patients

Noriko Kodama,Kiyoshi Komuta,Hiroaki Nanba 한국식품영양과학회 2003 Journal of medicinal food Vol.6 No.4

Maitake D-Fraction, extracted from maitake mushroom, has been reported to exert its antitumor effect in tu-mor-bearing mice by enhancing the immune system through activation of macrophages, T cells, and natural killer (NK) cells.In a previous study, the combination of immunotherapy with the maitake D-Fraction and chemotherapy suggested that the D-Fraction may have the potential to decrease the size of lung, liver, and breast tumors in cancer patients. In the present study,we administered maitake D-Fraction to cancer patients without anticancer drugs, and at the same time NK cell activity wasmonitored to investigate whether the activity is closely related with disease progression. The numbers of CD4 1 and CD81cells in the peripheral blood were measured in 10 patients, and NK cell activity was assessed using K-562 cells as target cells.Serum soluble interleukin-2 receptor (sIL-2R) levels in three patients and the expression of tumor markers in four patientswere determined by enzyme-linked immunosorbent assay. The slight changes observed in the CD4 1 and CD81 cell numberswere independent of disease severity or stage as well as serum sIL-2R levels. In contrast, maitake D-Fraction hindered metasta-tic progress, lessened the expression of tumor markers, and increased NK cell activity in all patients examined. Thus maitakeD-Fraction appears to repress cancer progression and primarily exerts its effect through stimulation of NK activity. In addi-tion, we conclude that measurement of NK cell activity may be a useful clinical parameter in monitoring disease progressionduring and following immunotherapy with maitake D-Fraction.

Administration of a Polysaccharide from Grifola frondosa Stimulates Immune Function of Normal Mice

Noriko Kodama,Yukihito Murata,Hiroaki Nanba 한국식품영양과학회 2004 Journal of medicinal food Vol.7 No.2

Potential Antitumor Activity of a Low-Molecular-Weight Protein Fraction from Grifola frondosa Through Enhancement of Cytokine Production

Noriko Kodama,Shigeto Mizuno,Hiroaki Nanba,Naoaki Saito 한국식품영양과학회 2010 Journal of medicinal food Vol.13 No.1

Edible mushrooms contain an abundance of immune-enhancing nutrients. Some of these compounds, referred to as biological response modifiers (BRMs), have been used in biological therapies for cancer treatment. We obtained a low-molecular-weight protein fraction (MLP-Fraction) from the fruiting body of the maitake mushroom Grifola frondosa by multiple sequential steps, including ethanol precipitation, DEAE-exchange chromatography, and gel filtration. The effect of the MLP-Fraction on the immune system was determined using normal mice. This resulted in a simultaneous increase in splenocyte proliferation and production of cytokines such as interleukin (IL)-1α, tumor necrosis factor-α, IL-10, IL-12, and interferon (IFN)-γ. The expression levels of IFN-γ and IL-12 in antigen-presenting cells (APCs) and the activation of natural killer (NK) cells, macrophages, and dendritic cells were observed. These results suggest a mechanism in which NK cells are activated through cytokines produced by APCs. We also confirmed the possibility that the MLP-Fraction acts as a BRM using colon-26 carcinoma-bearing mice. This fraction enhanced the production of IL-12 and IFN-γ by splenocytes in tumor-bearing mice and clearly showed an inhibitory effect on tumor cell growth.

Molecular swithes of transgene overexpression and cosuppression

Sayaka Hirai,Hiroaki Kodama 한국작물학회 2007 한국작물학회 학술발표대회 논문집 Vol.2007 No.11

Effect of water temperature on survival of early-life stages of marbled flounder <i>Pseudopleuronectes yokohamae</i> in Tokyo Bay, Japan

Lee, Jeong-Hoon,Kodama, Keita,Oyama, Masaaki,Shiraishi, Hiroaki,Horiguchi, Toshihiro Elsevier 2017 Marine environmental research Vol.128 No.-

<P><B>Abstract</B></P> <P>We investigated factors that might have disturbed the stock recovery of marbled flounder in Tokyo Bay by focusing on the early life stages. Field surveys in Tokyo Bay from 2006 to 2011 revealed that mature adult biomass increased from 2006 to 2008 and decreased thereafter. Meanwhile, larval and juvenile densities were high in 2006 and 2008 but low in other years. Discrepancies in the yearly trends of these parameters suggest that mortality during life stages between spawning and early larval phases might have affected the abundance of the subsequent life stages. Monthly mean water temperature between January and February, in which hatching and pelagic larvae occur in the bay, was lower in 2006 (8.6 °C) and 2008 (9.6 °C) than was observed in other years (10.4–11.4 °C). Significant negative correlation between water temperature and larval density implies that mortality during pre- and post-larval stages would be higher in warmer winter years (>10 °C). To test this hypothesis, we examined the effects of water temperature on mortality and development in egg and larval stages under controlled laboratory conditions. Hatching rate was high in a water temperature range of 9.2–12.7 °C (66.6–82.5%), whereas it decreased in cooler (3.7% at 5.9 °C) or warmer (33.9% at 14.8 °C) conditions. Meanwhile, days from fertilization to hatching, size of larvae at hatching and survival rate of larvae after 18 d from hatching were monotonically and significantly decreased as water temperature was elevated. Combined evidence of the field and laboratory studies suggests that a warmer reproductive season (>10 °C) might induce mortalities of marbled flounder larvae in Tokyo Bay.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Effects of temperature on the early life stages of marbled flounder were examined. </LI> <LI> Larval and juvenile densities in Tokyo Bay were low during warmer winter years >10 °C. </LI> <LI> High larval mortality in warmer conditions was confirmed by laboratory experiments. </LI> <LI> Elevated temperature during reproductive season may result in recruitment failure. </LI> </UL> </P>

PSLX: Interoperable Software Implementation Platform for Manufacturing Operations Management

Yasuyuki Nishioka,Tomohiko Maeda,Hiroaki Sasaki,Kiminobu Kodama,Shinsuke Nomoto,Akihito Ito 제어로봇시스템학회 2009 제어로봇시스템학회 국제학술대회 논문집 Vol.2009 No.8

Protein 2b of Cucumber mosaic virus strains IA and SD preferentially suppresses RDR6-dependent silencing pathway

Mayuko Shimokawa,Sayaka Hirai,Hiroaki Kodama 한국식물생명공학회 2019 Plant biotechnology reports Vol.13 No.2

The 2b protein of Cucumber mosaic virus (CMV) subgroup IB strain IA (IA2b) suppresses the sense transgene-induced posttranscriptional gene silencing (S-PTGS) but not the inverted repeat-induced post-transcriptional gene silencing (IR-PTGS) of a tobacco microsome-localized α-linolenate synthase gene (NtFAD3). In contrast, the 2b protein of CMV subgroup IB strain SD (SD2b) has been reported to suppress IR-PTGS. We overexpressed the SD2b gene in tobacco, and this transgenic line was crossed with the transgenic plants showing S-PTGS and IR-PTGS of the NtFAD3 gene. The phenotype of offspring showed that SD2b inhibited S-PTGS but not IR-PTGS. Next, we determined the suppressor activity of IA2b and SD2b proteins in a transient IR-PTGS assay. The transient expression of firefly luciferase (LUC) gene was efficiently decreased by IR-PTGS. Co-infiltration of SD2b and IA2b gene partially suppressed IR-PTGS of the LUC gene in the wild-type plants; however, these 2b proteins did not suppress IR-PTGS in the RNA-dependent RNA polymerase6 (RDR6) knockdown plants. It has been reported that RDR6-dependent secondary small interfering RNA synthesis does not occur in the IR-PTGS, when targeting endogenous genes such as NtFAD3, but is efficiently induced in the IR-PTGS of the reporter transgenes. These results indicate that the SD2b and IA2b preferentially suppress the RDR6-dependent silencing pathway but do not suppress the RDR6-independent IR-PTGS pathway.

Cosuppression and RNAi induced by Arabidopsis ortholog gene sequences in tobacco

Oka, Shin-Ichiro,Midorikawa, Kaoru,Kodama, Hiroaki The Korean Society of Plant Biotechnology 2010 Plant biotechnology reports Vol.4 No.3

The Arabidopsis ${\omega}$-3 fatty acid desaturase (AtFAD7) catalyzes the synthesis of trienoic fatty acids (TA). A transgenic tobacco line, T15, was produced by a sense AtFAD7 construct and showed a cosuppression-like phenotype, namely extremely low TA levels. The sequence similarity between AtFAD7 and a tobacco ortholog gene, NtFAD7, was moderate (about 69%) in the coding sequences. AtFAD7 siRNAs accumulated at a high level, and both AtFAD7 and NtFAD7 mRNAs are degraded in T15 plants. The low-TA phenotype in T15 was dependent on a tobacco RNA-dependent RNA polymerase6 (NtRDR6). We also produced tobacco RNAi plants targeting AtFAD7 gene sequences. The AtFAD7 siRNA level was trace, which was associated with a slight reduction in leaf TA level. Unexpectedly, this RNAi plant showed an increased NtFAD7 transcript level. To investigate the effect of translational inhibition on stability of the NtFAD7 mRNAs, leaves of the wild-type tobacco plants were treated with a translational inhibitor, cycloheximide. The level of NtFAD7 mRNAs significantly increased after cycloheximde treatment. These results suggest that the translational inhibition by low levels of AtFAD7 siRNAs or by cycloheximide increased stability of NtFAD7 mRNA. The degree of silencing by an RNAi construct targeting the AtFAD7 gene was increased by co-existence of the AtFAD7 transgene, where NtRDR6-dependent amplification of siRNAs occurred. These results indicate that NtRDR6 can emphasize silencing effects in both cosuppression and RNAi.

The 5′ UTR intron-mediated enhancement of constitutive splicing of the tobacco microsome ω-3 fatty acid desaturase gene

Sayuri Ohta,Sakie Nakagawara,Sayaka Hirai,Kumi Miyagishima,Gorou Horiguchi,Hiroaki Kodama 한국식물생명공학회 2018 Plant biotechnology reports Vol.12 No.2

Several plant genes have their first intron in the 5′ untranslated region (5′ UTR), and such 5′ UTR introns often show several biological functions, including the intron-mediated enhancement of protein expression through an increase of mRNA level (IME), intron-dependent spatial expression, and intron-mediated enhancement of translation. Here, we show another function of the 5′ UTR intron, i.e., the 5′ UTR intron-mediated enhancement of constitutive splicing. The NtFAD3 gene, which encodes a tobacco microsome ω-3 fatty acid desaturase, has a 552 nucleotide-long 5′ UTR intron (intron 1), and the other seven introns are located in the coding sequence. The splicing of the 5′ half region of the NtFAD3 was studied through an in vivo splicing assay using Arabidopsis leaf explants. The low splicing efficiency of intron 2 was much improved when the assay construct harbored intron 1. Deletion of intron 1 and the replacement of intron 1 to the NtFAD3 intron 8 decreased the splicing efficiency of intron 2. The splicing enhancers were redundant and dispersed in the 5′ splice site-proximal, 284-nucleotides region of intron 1. In addition, the interaction among the cis-elements, i.e., the splicing enhancers in the intron 1 and exon 2, were necessary for the efficient splicing of intron 2. The 5′ UTR intron-mediated constitutive splicing was partially inhibited when an SR-like protein, SR45, was deficient. These results indicated a novel function of the 5′ UTR intron, namely an enhancement of the constitutive splicing.

Transformation efficiency and transgene expression level in markerfree RDR6-knockdown transgenic tobacco plants

Tatsuya Mikami,Yuta Saeki,Sayaka Hirai,Mayuko Shimokawa,Yukiko Umeyama,Yusaku Kuroda,Hiroaki Kodama 한국식물생명공학회 2018 Plant biotechnology reports Vol.12 No.6

RNA silencing is a sequence-specific form of epigenetic regulation that targets invasive nucleic acids. RNA-dependent RNA polymerase6 (RDR6) converts target RNA molecules, such as transgene transcripts, into double-stranded RNAs (dsRNAs) during posttranscriptional gene silencing (PTGS). Then, these dsRNAs are processed into small RNAs that guide sequencespecific RNA degradation. T-DNA-derived small RNAs are generated during the transfer of T-DNA from Agrobacterium to plant cells and compromise the function of the genes in the T-DNA. In the present study, we produced selection-markerfree transgenic tobacco plants using the MAT vector system, and expression of the tobacco RDR6 gene (NtRDR6) was suppressed using inverted-repeat-induced PTGS. Reduced expression of the NtRDR6 gene improved the transient expression of the transgene in the agroinfiltrated leaves and enhanced the production of hairy roots after infection with Agrobacterium containing a root-inducing T-DNA. The expression level of the sense transgene was determined in individual hairy roots, and knockdown of the NtRDR6 gene did not affect the distribution of the expression levels in individual transformants. These results indicate that NtRDR6 partially inhibited T-DNA function during T-DNA transfer but did not affect the expression of the transgene in stable transformants, except in transformants showing sense-transgene-induced PTGS.