• Title/Summary/Keyword: CD3 stimulation

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CD40 Co-stimulation Inhibits Sustained BCR-induced $Ca^{2+}$ Signaling in Response to Long-term Antigenic Stimulation of Immature B Cells

  • Nguyen, Yen Hoang;Lee, Ki-Young;Kim, Tae-Jin;Kim, Sung-Joon;Kang, Tong-Mook
    • The Korean Journal of Physiology and Pharmacology
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    • v.15 no.3
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    • pp.179-187
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    • 2011
  • Regulation of B cell receptor (BCR)-induced $Ca^{2+}$ signaling by CD40 co-stimulation was compared in long-term BCR-stimulated immature (WEHI-231) and mature (Bal-17) B cells. In response to long-term pre-stimulation of immature WEHI-231 cells to ${\alpha}$-IgM antibody (0.5~48 hr), the initial transient decrease in BCR-induced $[Ca^{2+}]_i$ was followed by spontaneous recovery to control level within 24 hr. The recovery of $Ca^{2+}$ signaling in WEHI-231 cells was not due to restoration of internalized receptor but instead to an increase in the levels of $PLC{\gamma}2$ and $IP_3R-3$. CD40 co-stimulation of WEHI-231 cells prevented BCR-induced cell cycle arrest and apoptosis, and it strongly inhibited the recovery of BCR-induced $Ca^{2+}$ signaling. CD40 co-stimulation also enhanced BCR internalization and reduced expression of $PLC{\gamma}2$ and $IP_3R-3$. Pre-treatment of WEHI-231 cells with the antioxidant N-acetyl-L-cysteine (NAC) strongly inhibited CD40-mediated prevention of the recovery of $Ca^{2+}$ signaling. In contrast to immature WEHI-231 cells, identical long-term ${\alpha}$-IgM pre-stimulation of mature Bal-17 cells abolished the increase in BCR-induced $[Ca^{2+}]_i$, regardless of CD40 co-stimulation. These results suggest that CD40-mediated signaling prevents antigen-induced cell cycle arrest and apoptosis of immature B cells through inhibition of sustained BCR-induced $Ca^{2+}$ signaling.

Differential Signaling via Tumor Necrosis Factor-Associated Factors (TRAFs) by CD27 and CD40 in Mouse B Cells

  • Woo, So-Youn;Park, Hae-Kyung;Bishop, Gail A.
    • IMMUNE NETWORK
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    • v.4 no.3
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    • pp.143-154
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    • 2004
  • Background: CD27 is recently known as a memory B cell marker and is mainly expressed in activated T cells, some B cell population and NK cells. CD27 is a member of tumor necrosis factor receptor family. Like CD40 molecule, CD27 has (P/S/T/A) X(Q/E)E motif for interacting with TNF receptor-associated factors (TRAFs), and TRAF2 and TRAF5 bindings to CD27 in 293T cells were reported. Methods: To investigate the CD27 signaling effect in B cells, human CD40 extracellular domain containing mouse CD27 cytoplamic domain construct (hCD40-mCD27) was transfected into mouse B cell line CH12.LX and M12.4.1. Results: Through the stimulation of hCD40-mCD27 molecule via anti-human CD40 antibody or CD154 ligation, expression of CD11a, CD23, CD54, CD70 and CD80 were increased and secretion of IgM was induced, which were comparable to the effect of CD40 stimulation. TRAF2 and TRAF3 were recruited into lipid-enriched membrane raft and were bound to CD27 in M12.4.1 cells. CD27 stimulation, however, did not increase TRAF2 or TRAF3 degradation. Conclusion: In contrast to CD40 signaling pathway, TRAF2 and TRAF3 degradation was not observed after CD27 stimulation and it might contribute to prolonged B cell activation through CD27 signaling.

Expression and Function of TLR2 on CD4 Versus CD8 T Cells

  • Lee, Sun-Mi;Joo, Young-Don;Seo, Su-Kil
    • IMMUNE NETWORK
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    • v.9 no.4
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    • pp.127-132
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    • 2009
  • Background: Toll-like receptors (TLRs) play a fundamental role in innate immunity through their capacity to recognize pathogen-associated molecular patterns. Also, TLRs that are expressed in T cells are reported to function as co-stimulatory receptors. However, the functional capacity of TLRs on CD4 T and CD8 T cells has not been directly compared. Here we compared CD4 and CD8 T cell responses to TLR2 ligand plus TCR-mediated stimulation. Methods: TLR2 expression was analyzed on T cell subsets under naive and alloantigen-primed conditions. We analyzed the effects of TLR2 co-stimulation on proliferation and survival of T cell subsets in vitro when stimulated with soluble anti-CD3 in the presence or absence of synthetic ligand $Pam_3CSK_4$. Results: TLR2 expression on CD8 T cells was induced following activation; this expression was much higher than on CD4 T cells. Thus, the molecule was constitutively expressed on Listeriaspecific memory CD8 T cells. Based on these expression levels, proliferation and survival were markedly elevated in CD8 T cells in response to the TLR2 co-stimulation by $Pam_3CSK_4$ compared with those in CD4 T cells. Conclusion: Our data show that TLR2 co-stimulation is more responsible for proliferation and survival of CD8 T cells than for that of CD4 T cells.

The Stimulation of CD147 Induces MMP-9 Expression through ERK and NF-${\kappa}B$ in Macrophages: Implication for Atherosclerosis

  • Kim, Ju-Young;Kim, Won-Jung;Kim, Ho;Suk, Kyoung-Ho;Lee, Won-Ha
    • IMMUNE NETWORK
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    • v.9 no.3
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    • pp.90-97
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    • 2009
  • Background: CD147, as a cellular receptor for cyclophilin A (CypA), is a multifunctional protein involved in tumor invasion, inflammation, tissue remodeling, neural function, and reproduction. Recent observations showing the expression of CD147 in leukocytes indicate that this molecule may have roles in inflammation. Methods: In order to investigate the role of CD147 and its ligand in the pathogenesis of atherosclerosis, human atherosclerotic plaques were analyzed for the expression pattern of CD147 and CypA. The cellular responses and signaling molecules activated by the stimulation of CD147 were then investigated in the human macrophage cell line, THP-1, which expresses high basal level of CD147 on the cell surface. Results: Staining of both CD147 and CypA was detected in endothelial cell layers facing the lumen and macrophage-rich areas. Stimulation of CD147 with its specific monoclonal antibody induced the expression of matrix metalloproteinase (MMP)-9 in THP-1 cells and it was suppressed by inhibitors of both ERK and NF-${\kappa}B$. Accordingly, the stimulation of CD147 was observed to induce phosphorylation of ERK, phosphorylation-associated degradation of $I{\kappa}B$, and nuclear translocation of NF-${\kappa}B$ p65 and p50 subunits. Conclusion: These results suggest that CD147 mediates the inflammatory activation of macrophages that leads to the induction of MMP-9 expression, which could play a role in the pathogenesis of inflammatory diseases such as atherosclerosis.

Promotion of Nonspecific Cytotoxic T Lymphocyte Activity by Bo-yang-hwan-oh-tang (보양환오탕에 의한 비특이적 세포독성 T 세포 활성 증강)

  • Ha, Jong-Cheon;Kim, Young-Hyun;Woo, Won-Hong;Nam, Sang-Yun
    • Korean Journal of Pharmacognosy
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    • v.32 no.3 s.126
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    • pp.226-232
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    • 2001
  • To explore the possible cancer therapeutic application of "Bo-yang-hwan-oh-tang" (BH), a herbal medicinal recipe used for improvement of blood stasis, we have examined its direct cytotoxicity against tumor cell, and induction of cytotoxic activity of lymphocytes. Water extract of BH alone did not exhibit direct cytotoxicity to Yac-1 target cells even with high concentrations (10 mg/ml). By exposure for 3 days, BH did not induce any nonspecific cytotoxic activity of mouse spleen cells, either, when assessed in a 4 hr $^{51}Cr-release$ assay. However, when BH was added during CD3 stimulation of non-adherent spleen cells, non-specific CTL activity was markedly promoted in a dose dependent manner. In contrast, BH did not alter activated NK cell activity following IL-2 stimulation. These data suggest that BH does not induce but upregulates non-specific CTL effecter function and that activated NK cell does not respond to BH. For elucidation of the mechanism underlying this function of BH, time kinetic study for IL-2 production using ELISA was undertaken. IL-2 production following CD3 stimulation was significantly augmented and higher level of IL-2 is sustained over 3 days in the culture medium by BH treatment. Moreover, addition of exogenous IL-2 during CD3 stimulation resulted in a similar level of cytotoxicity between control and BH-treated culture. These data indicate that the BH-mediated upregulation of non-specific CTL activity is contributed by augmentation of IL-2 production. Our data imply the possible application of BH for combination therapy of cancer with non-specific activator.

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Alteration of Vascular Reactivity in Cadmium-poisoned Rabbits (카드뮴 중독(中毒)에 의한 이곡혈관운동성(耳穀血管運動性)의 변동(變動))

  • Hong, Ki-Whan;Rhim, Byung-Yong
    • The Korean Journal of Pharmacology
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    • v.18 no.1
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    • pp.23-31
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    • 1982
  • 1) Experiments were undertaken to elucidate the mechanism which elevates the systemic arterial blood pressure by cadmium (Cd). 2) The mean arterial pressure and peripheral resistance of central ear artery in Cd-poisoned rabbit were significantly increased in comparison with those in control. 3) The vascular pressure response to electrical stimulation in Cd-poisoned group was less than that in control. However, in the former group it showed the supersensitivity to norepinephrine. 4) The response to electrical stimulation was diminished by sodium arachidonate in the ear artery, on the contrary, it was rather enhanced in the vessel of Cd-poisoned group. The responses in both groups were reduced by pretreatment with either $PGE_2\;or\;PGF_{2{\alpha}}$. 5) The response to electrical stimulation was not affected in control, but enhanced in Cd-poisoned group by pretreatment with indomethacin. 6) When the ear artery of control group was perfused with physiological salt solution (PSS) the response to electrical stimulation was not changed by indomethacin, it was much enhanced without affecting on the response to norepinephrine when $K^+-free\;PSS$, was used. These results demonstrate the evidence that the alteration of regulatory mechanism on the vessels was causally related to the elevation of arterial pressure and the increase in peripheral resistance in Cd-poisoned rabbits.

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Alteration of ${\alpha}-Adrenoceptor$ by Cd-poisoning in Rat Vas Deferens and Tail Artery (카드뮴중독이 흰쥐 정관 및 꼬리동맥의 아드레나린성 ${\alpha}-$수용체에 미치는 영향)

  • Son, Bang-Hyun;Cho, Soo-Yeul;Lee, Sang-Il
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.14 no.3
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    • pp.253-258
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    • 1985
  • It was aimed to elucidate the underlying mechanism which is elevated the systemic arterial blood pressure by cadmium(Cd). By using the isolated vas deferens and tail artery from Cd-poisoned rats, it was undertaken to see whether the ${\alpha}-adrenoceptor$ activity and prostaglandins action on the twitch response to electrical stimulation were altered. It was discussed in relation with sympathetic nerve activity. The response to electrical stimulation in vas deferens from Cd-poisoned rats was much enhanced, and frequency 50(Freq.50) was significantly lowered, comparing to control. However, the response of rat tail artery was attenuated by Cd. Inhibitory action of clonidine on the twitch response of vas deferens to electrical stimulation was decreased by Cd-poisoning. However, the increase in response in the presence of methoxamine was not affected. The inhibitory action of prostaglandin $E_2$ on the twitch response in the vas deferens but not in the tail artery was abolished or rather inverted by Cd-poisoning. In the tail artery from Cd-poisoned rats, the maximum contraction to methoxamine or clonidine was significantly decreased, however, $ED_{50}$ of both agonists was not changed. These results suggest that in vas deferens the autoreceptor of presynaptic membrane is inhibited by Cd-poisoning, by which mechanism the sympathetic activity is being enhanced and this alteration may be causally related to the elevation of arterial pressure.

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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.

Immunological benefits by ginseng through reciprocal regulation of Th17 and Treg cells during cyclosporine-induced immunosuppression

  • Heo, Seong Beom;Lim, Sun Woo;Jhun, Joo Yeon;Cho, Mi La;Chung, Byung Ha;Yang, Chul Woo
    • Journal of Ginseng Research
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    • v.40 no.1
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    • pp.18-27
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    • 2016
  • Background: It is not clear whether ginseng affects cyclosporine A (CsA)-induced desirable immunosuppressive action. In this study, we evaluated the immunological influence of combined treatment of ginseng with CsA. Methods: Using CD4+ T cells from mouse spleens stimulated with the T cell receptor (TCR) or allogeneic antigen-presenting cells (APCs), we examined the differentiation of naïve T cells into T helper 1 (Th1), Th2, Th17, and regulatory T cells (Tregs), and their cytokine production during treatment by Korean Red Ginseng extract (KRGE) and/or CsA. The influence of KRGE on the allogeneic T cell response was evaluated by mixed lymphocyte reaction (MLR). We also evaluated whether signal transducer and activator of transcription 3 (STAT3) and STAT5 are implicated in this regulation. Results: Under TCR stimulation, KRGE treatment did not affect the population of CD4+interferon gamma ($IFN{\gamma}$)+ and CD4+interleukin (IL)-4+ cells and their cytokine production compared with CsA alone. Under the Th17-polarizing condition, KRGE significantly reduced the number of CD4+IL-17+ cells and CD4+/phosphorylated STAT3 (p-STAT3)+ cells, but increased the number of CD4+CD25+forkhead box P3 (Foxp3)+ cells and CD4+/p-STAT5+ cells compared with CsA alone. In allogeneic APCs-stimulated CD4+ T cells, KRGE significantly decreased total allogeneic T cell proliferation. Consistent with the effects of TCR stimulation, KRGE reduced the number of CD4+IL-17+ cells and increased the number of CD4+CD25+Foxp3+ cells under the Th17-polarizing condition. Conclusion: KRGE has immunological benefits through the reciprocal regulation of Th17 and Treg cells during CsA-induced immunosuppression.

Pallidal Deep Brain Stimulation in Primary Cervical Dystonia with Phasic Type : Clinical Outcome and Postoperative Course

  • Jeong, Seong-Gyu;Lee, Myung-Ki;Kang, Ju-Young;Jun, Sung-Man;Lee, Won-Ho;Ghang, Chang-Ghu
    • Journal of Korean Neurosurgical Society
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    • v.46 no.4
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    • pp.346-350
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    • 2009
  • Objective : The purpose of this study was to analyze in detail the relationship between outcome and time course of effect in medically refractory primary cervical dystonia (CD) with phasic type that was treated by bilateral globus pallidus internus (Gpi) deep brain stimulation (DBS). Methods : Six patients underwent bilateral implantation of DBS into the Gpi under the guide of microelectrode recording and were followed for $18.7{\pm}11.1$ months. The mean duration of the CD was $5.8{\pm}3.4$ years. The mean age at time of surgery was $54.2{\pm}10.2$ years. Patients were evaluated with the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) and relief scale using patient self-reporting. Results : The TWSTRS total scores improved by 64.5%, 65.5%, 75.8%, and 76.0% at 3, 6, 12 months, and at the last available follow-up after surgery, respectively. Statistically significant improvements in the TWSTRS scores were observed 3 months after surgery (p=0.028) with gradual improvement up to 12 months after surgery, thereafter, the improvement was sustained. However, there was no statistically significant difference between the scores at 3 and 12 months. Subjective improvement reported averaged $81.7{\pm}6.8%$ at last follow-up. Mild dysarthria, the most frequent adverse event, occurred in 3 patients. Conclusions : Our results show that the bilateral Gpi-DBS can offer a significant therapeutic effect from 3 months postoperatively in patients with primary CD with phasic type, without significant side effects.