• Title/Summary/Keyword: B cells

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Water Extract of Kudzu Root (Pueraria radix) Decreases Apolipoprotein B100 and B48 Production in Vitro

  • Lee, Jeong-Sook
    • Preventive Nutrition and Food Science
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    • v.7 no.4
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    • pp.353-357
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    • 2002
  • We have previously demonstrated that kudzu root extracts have a hypocholesterolemic effect on rats fed diets high in fat and cholesterol. To further elucidate the mechanism involved, in this study we investigated the effect of water extracts of kudzu root, Pueraria radix, on the production of apolipoprotein B$_{100}$ (APo B$_{100}$) in HepG$_2$ liver cells and secretion of apolipoprotein B$_{48}$ (Apo B$_{48}$) in Caco$_2$ cells. Human cell lines, HepG$_2$ liver cells and Caco$_2$ intestinal epithelial cells, were grown with various concentrations (0%, 0.5%, 1.0%, 1.5%, 2.0%) of water extracts of kudzu root in the media. The kudzu root extract decreased Apo B$_{100}$ production and secretion. Treatment of HeP G$_2$ cells with the kudzu root extract also significantly decreased the intracellular total and free cholesterol concentration, and also decreased esterified cholesterol but was only significant at the highest dose of 2%. Apo B$_{48}$ production, but not secretion, from enterocytes was lowered by the kudzu root extracts. This research provided evidence that the hypocholesterolemic properties of kudzu root may be a consequence of decreased production and secretion of Apo B$_{100}$ in the liver and Apo B$_{48}$ in the intestine.

Effect of Water Extract of Carthamus tinctorious L. on In Vitro Activity of T and B Lymphocytes (시험관내에서 홍화의 물 추출물이 T 및 B 림프구의 활성에 미치는 영향)

  • Choi, Youn-Hwa;Do, Jeong-Su;Nam, Sang-Yun
    • Korean Journal of Pharmacognosy
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    • v.35 no.4 s.139
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    • pp.330-337
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    • 2004
  • Based on the traditional application of Carthamus tinctorious L. (CF) as a component of Korean medicinal decoctions, in the present study, we investigated in vitro an immunomodulatory activity of water extract of CF(WECF). Water extract of CF significantly increased the in vitro proliferative responses of spleen cells (SPC). However, addition of WECF during anti-CD3 activation resulted in a significant decrease in SPC proliferation. Flow cytometric analysis showed that WECF addition chanced T and B cell frequencies in anti-CD3-activated spleen cell populations. Using purified cells, it was revealed that WECF is mitogenic to B cells but rather inhibitory to T cell Proliferation. Upon anti-CD3 stimulation, high concentration (1 mg/ml) of WECF significantly inhibited T cell proliferation until day 2 of stimulation. At day 3, anti-CD3-activated cells exposed to WECF recovered their proliferation to the level comparable to control. Although B cell proliferation was also inhibited in proliferation at day 1, it recovered sooner and then was rather augmented by WECF at day 3. These data indicate that WECF down-regulates lymphocyte proliferation at early phase of activation but T cells are more vulnerable than B cells to WECF, However, CD4+ and CD8+ T cells did not differ in WECF-mediated immunotoxicity. Data of propidium iodide (PI) staining showed that WECF accelerates activated T cell, but not B cell, apoptosis and WECF concurrently inhibited cytokine production of activated T cells. Taken together, WECF exhibits B cell mitogenic activity and differential toxicity more pronounced to T cells, suggesting a possible in vivo application of WECF for specific control of T cells without alteration of B cell activity.

Pancastatin A and B Have Selective Cytotoxicity on Glucose-Deprived PANC-1 Human Pancreatic Cancer Cells

  • Park, Hae-Ryong
    • Journal of Microbiology and Biotechnology
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    • v.30 no.5
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    • pp.733-738
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    • 2020
  • Glucose deprivation and hypoxia frequently occur in solid tumor cells, including pancreatic cancer cells. Glucose deprivation activates the unfolded protein response (UPR) and causes the up-regulation of glucose-regulated protein 78 (GRP78). Induction of GRP78 has been shown to protect cancer cells. Therefore, shutting down of GRP78 expression may be a novel strategy in anticancer drug development. Based on this understanding, a screening system established for anticancer agents that exhibit selective cytotoxicity on pancreatic cancer cells under glucose-deprived conditions. To test this hypothesis, the new compounds isolated, pancastatin A (PST-A) and B (PST-B), from Ponciri Fructus. PST-A and B were identified as glabretal triterpenoid moieties by electrospray ionization mass spectrometry and nuclear magnetic resonance spectroscopic methods. PST-A and B suppressed the accumulation of the UPR hallmark gene, GRP78, during glucose deprivation. Furthermore, PST-A and B showed selective cytotoxicity on PANC-1 pancreatic cancer cells under glucose deprivation. Interestingly, PST-A and B had no effect on these cells under normal growth conditions. Our results suggest that PST-A and B act as novel therapeutic agents to induce selective cell death in glucose-deprived pancreatic cancer cells.

Forced Expression of HoxB4 Enhances Hematopoietic Differentiation by Human Embryonic Stem Cells

  • Lee, Gab Sang;Kim, Byung Soo;Sheih, Jae-hung;Moore, Malcolm AS
    • Molecules and Cells
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    • v.25 no.4
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    • pp.487-493
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    • 2008
  • HoxB4 has been shown to enhance hematopoietic engraftment by hematopoietic stem cells (HSC) from differentiating mouse embryonic stem cell (mESC) cultures. Here we examined the effect of ectopic expression of HoxB4 in differentiated human embryonic stem cells (hESCs). Stable HoxB4-expressing hESCs were established by lentiviral transduction, and the forced expression of HoxB4 did not affect stem cell features. HoxB4-expressing hESC-derived CD34+ cells generated higher numbers of erythroid and blast-like colonies than controls. The number of CD34+ cells increased but CD45+ and KDR+ cell numbers were not significantly affected. When the hESC derived CD34+ cells were transplanted into $NOD/SCID{\beta}2m-/-$ mice, the ectopic expression of HoxB4 did not alter their repopulating capacity. Our findings show that overexpression of HoxB4 in differentiating hESCs increases hematopoietic colony formation and hematopoietic cell formation in vitro, but does not affect in vivo repopulation in adult mice hosts.

MiR-133b Acts as a Tumor Suppressor and Negatively Regulates TBPL1 in Colorectal Cancer Cells

  • Xiang, Kai-Min;Li, Xiao-Rong
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.8
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    • pp.3767-3772
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    • 2014
  • Introduction: MicroRNAs have emerged as post-transcriptional regulators that are critically involved in tumorigenesis. This study was designed to explore the effect of miRNA 133b on the proliferation and expression of TBPL1 in colon cancer cells. Methods: Human colon cancer SW-620 cells and human colon adenocarcinoma HT-29 cells were cultured. MiRNA 133b mimcs, miRNA 133b inhibitors, siRNA for TBPL1 and scrambled control were synthesized and transfected into cells. MiR-133b levels in cells and CRC tumor tissue was measured by real-time PCR. TBPL1 mRNA was detected by RT-PCR. Cell proliferation was studied with MTT assay. Western blotting was applied to detect TBPL1 protein levels. Luciferase assays were conducted using a pGL3-promoter vector cloned with full length of 3'UTR of human TBPL1 or 3'UTR with mutant sequence of miR-133b target site in order to confirm if the putative binding site is responsible for the negative regulation of TBPL1 by miR-133b. Results: Real time PCR results showed that miRNA 133b was lower in CRC tissue than that in adjacent tissue. After miR-133b transfection, its level was elevated till 48h, accompanied by lower proliferation in both SW-620 and HT-29 cells. According to that listed in http://www.targetscan.org, the 3'-UTR of TBPL1 mRNA (NM_004865) contains one putative binding site of miR-133b. This site was confirmed to be responsible for the negative regulation by miR-133b with luciferase assay. Further, Western blotting and immunohistochemistry both indicated a higher TBPL1 protein expression level in CRC tissue. Finally, a siRNA for TBPL1 transfection obviously slowed down the cell proliferation in both SW-620 and HT-29 cells. Conclusion: MiR-133b might act as a tumor suppressor and negatively regulate TBPL1 in CRC.

The effects of the abstracts from Moutan Cortex on an anti-allergic action on B cells and mast cells of the BALB/C mouse (B 임파구(淋巴球)와 비만세포(肥滿細胞)에서 모단피(牡丹皮) 추출물(抽出物)의 항(抗)알러지 작용(作用)에 관(關)한 연구(硏究))

  • Jeen Sok-Chang;Kim Sung-Kyun;Lee Han-Bae;Lee Seung-Hee;Seo Young-Bae;Lee Yong-Gu;Lee Young-Chul;Jang Sung-Ik
    • The Journal of Internal Korean Medicine
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    • v.24 no.1
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    • pp.33-43
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    • 2003
  • Objective : This study was carried out for the purpose of proving the effect of anti-allergic efficacy on B cells and the mast cells of the BALB/C mouse by the abstraction from a Moutan cortex. Methods & Results : In order to know what the effect of an abstraction from Moutan cortex and about the expression of CD23 and IgE, IC-2 cell (mouse mast precursor cells that was dependent on IL-3), it was necessary to be activated. We then analyzed it from the flow of cytometry on the increase and the divorce of the B cells activated by anti-CD40. In order to know what the effect of it was on the organization of cytokine gene expression from the increase and divorce of the B cells and allergic acting by Moutan cortex, we found it necessary to examine the IC-2 cells and B cells. At the same time, as we examined the histamine release of IC-2 cells by ELISA method, we also examined the effect of Moutan cortex on the increase and divorce of the B cells by 3H-thymidine uptake method. We then analyzed the release of IL-4, IgE and histamine. Conclusions : As a results, Moutan Cortex promoted blood supply by extending the blood vessel of nasal mucous, which was contracted by the hypertrophied nasal mucous.

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Effect of Chitosan Oligosaccharide on Melanin Production in B16 Melanoma Cells (B16 Melanoma 세포에서 Chitosan Oligosaccharide가 Melanin 생성에 미치는 영향)

  • 조남영;윤미연;김경원;박영미;임혜원;이지윤;이진희;김연정;김창종
    • YAKHAK HOEJI
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    • v.47 no.6
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    • pp.404-409
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    • 2003
  • To investigate the effect of chitosan oligosaccharide on melanin synthesis, we measured tyrosinase activity and melanin production in B16 melanoma cells. Chitosan oligosacchaide itself did not have any anti-oxidant activity in DPPH radical scavenging, and did not affect the proliferation of B16 melanoma cells. Chitosan oligosaccharide dose-dependently increased melanin production in the absence or presence of MSH. However, chitosan oligosaccharide did not have any influence on the tyrosinase activity and tyrosinase expression in B16 melanoma cells. These results suggest that chitosan oligosaccharide-induced melanin production may be independent on tyrosinase activity in B16 melanoma cells. From the above results. chitosan oligosaccharide dose-dependently appears to increase melanin production in B16 melanoma cells, suggesting that chitosan oligosaccharide may be used as a tanning agent.

Effects of Dokhwalkisaeng-tang on Melanin Synthesis Inhibition and Gene Expression in B16F10 Melanoma Cells (독활기생탕(獨活寄生湯)이 멜라닌 생성억제 및 유전자 발현에 미치는 영향)

  • Oh, Won-Kyo;Kim, Ki-Byoung;Lim, Jin-Young;Lee, Su-Kyung;Kwon, Young-Dal;Yeom, Seung-Ryong;Song, Yung-Sun
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.23 no.1
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    • pp.63-75
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    • 2009
  • The aim of this study was to elucidate the antimelanogenic effect of Dokhwalkisaeng-tang(Duohujisheng-tang) in B16F10 melanoma cells. Dokhwalkisaeng-tang(DKT) was used to develop the effective prescription of inhibition of melanin production. We determined inhibitory effects of DKT on melanin-release, melanin production, and tyrosinase activity in B16F10 melanoma cells. And to explicate the action-mechanism of DKT, melanin-related gene expressions were determined using RT-PCR and real time RT PCR technique in B16F10 melanoma cells. DKT inhibited melanin-release, melanin production in B16F10 melanoma cells considerably. DKT inhibited tyrosinase activity in vitro and in B16F10 melanoma cells. DKT inhibited the expression of tyrosinase, TRP-1, TRP-2 in B16F10 melanoma cells. DKT inhibited the expression of PKA, PKC, MMP-2 and MITF in B16F10 melanoma cells. On the other hand, DKT increased the expression of ERK-1, ERK-2, AKT-1 in B16F10 melanoma cells. From these results, we propose that DKT may have effect on the antimelanogenesis.

Autophagy-Dependent Survival of Mutant B-Raf Melanoma Cells Selected for Resistance to Apoptosis Induced by Inhibitors against Oncogenic B-Raf

  • Ahn, Jun-Ho;Lee, Michael
    • Biomolecules & Therapeutics
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    • v.21 no.2
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    • pp.114-120
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    • 2013
  • Most patients with mutant B-Raf melanomas respond to inhibitors of oncogenic B-Raf but resistance eventually emerges. To better understand the mechanisms that determine the long-term responses of mutant B-Raf melanoma cells to B-Raf inhibitor, we used chronic selection to establish B-Raf (V600E) melanoma clones with acquired resistance to the new oncogenic B-Raf inhibitor UI-152. Whereas the parental A375P cells were highly sensitive to UI-152 ($IC_{50}$ < $0.5{\mu}M$), the resistant sub-line (A375P/Mdr) displayed strong resistance to UI-152 ($IC_{50}$ < $20{\mu}M$). Immunofluorescence analysis indicated the absence of an increase in the levels of P-glycoprotein multidrug resistance (MDR) transporter in A375P/Mdr cells, suggesting that resistance was not attributable to P-glycoprotein overexpression. In UI-152-sensitive A375P cells, the anti-proliferative activity of UI-152 appeared to be due to cell-cycle arrest at $G_0/G_1$ with the induction of apoptosis. However, we found that A375P/Mdr cells were resistant to the apoptosis induced by UI-152. Interestingly, UI-152 preferentially induced autophagy in A375P/Mdr cells but not in A375P cells, as determined by GFP-LC3 puncta/cell counts. Further, autophagy inhibition with 3-methyladenine (3-MA) partially augmented growth inhibition of A375P/Mdr cells by UI-152, which implies that a high level of autophagy may protect UI-152-treated cells from undergoing growth inhibition. Together, our data implicate high rates of autophagy as a key mechanism of acquired resistance to the oncogenic B-Raf inhibitor, in support of clinical studies in which combination therapy with autophagy targeted drugs is being designed to overcome resistance.

The Characteristics of $V_H$ Gene Family Expression in Early B Cells (어린 B세포가 갖는 $V_H$유전자 발현의 특성)

  • JEONG Hyun Do;HUH Min-Do
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.28 no.1
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    • pp.114-122
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    • 1995
  • Defining the mechanisms of B cell diversification which establish the immune repertoire is fundamental to understand how the immune response is regulated. In this report, B cell differentiation and diversification focused on the regulation of immunoglobulin $V_H$ gene expression during ontogeny were analyzed by in situ hybridization technique. Fetal liver B cells in .different gestational days from 16d to 20d showed the predominant expression of $V_H7183$ and $V_HQ52$ without transition of repertoire during the observed gestation days. The two subsets of fetal liver B cells separated according to different differentiation stages based on the presence of tell surface immunoglobulin also did not indicate apparent difference in expressed $V_H$ gene family profiles. B cells in fetal spleen as an another hematopoietic lymphoid tissue in fetus also expressed similar $V_H$ gene repertoire to that in fetal liver B cells. This distinct pattern of $V_H$ gene expression in fetal B cells from that of adult B cells were not changed even after four weeks contact with adult bone marrow microenvironment supplied by the established adult bone marrow stromal cell layers. Thus, the restricted $V_H$ gene repertoire of B cells in fetus which is distinct from that in adult appears to be associated more with the genetic potential of fetal B cell progenitors and less with environmental influences or differentiation stages or compartmentalization.

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