• IMMUNE NETWORK
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• v.1 no.3
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• pp.196-202
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• 2001

Backgorund: WEHI-231 B cell line is a representative model for $IgM^+$ mature B cells. To understand the signaling differences between mature and immature B cells, we compared the responsiveness of WEHI-231 and Bal 17 B cell lines to BCR cross-linking. Methods: The extents of tyrosine phosphorylation, ligand-induced internalization, and activation-induced cell death upon BCR cross-linking were compared in two cell lines. Results: Despite a higher expression of BCR, cross-linking of BCR on WEHI-231 cell evoked a weaker level of tyrosine phosphorylation and BCR endocytosis than Bal 17 cells. Furthermore, the endocytosed BCR could not enter the lysosomal compartment and stayed as peripheral spots in WEHI-231 cells. Conclusion: WEHI-231 cell showed preferred BCR-mediated signaling pathways leading to a reduced capability of antigen presentation as well as the enhanced apoptosis in comparision with Bal 17 cells. These results might reflect the signaling differences between mature and immature B cells.

• BMB Reports
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• v.30 no.6
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• pp.415-420
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• 1997

Although $CD4^+$ T cell responses to protein-derived antigen have well been understood, the epitopes recognized by hapten-specific $CD4^+$ T cells have not been fully defined. In this study, we characterized the response of a T cell hybridoma (5Di0.1B8) which is specific for a hapten. N-hydroxysuccinimidyl-4-azidobenzoate (HSAB) restricted by MHC class II $I-A^d$. Using three different antigen presenting cells (APCs) expressing $I-A^d$, the role of class II MHC proteins in haptenic antigen presentation and subsequent activation of 5D10.1B8 has been examined. Activation of 5D10.1B8 T cells by HSAB analogs was also performed. Our results show that each APC activated T cells differentially and that interleukin-2 (IL-2) augmented antigen-presenting ability of all the APCs, suggesting that increased expression of class II MHC protein by IL-2 played an important role in HSAB presentation and T cell activation. Finally, early T cell receptor-dependent signals induced by HSAB or its analogs were examined by phosphotyrosine immunoblot analysis, and showed that tyrosine phosphorylation level of a 18-20 kD protein increased upon stimulation.

• IMMUNE NETWORK
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• v.13 no.5
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• pp.184-193
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• 2013

Co-signaling molecules are surface glycoproteins that positively or negatively regulate the T cell response to antigen. Co-signaling ligands and receptors crosstalk between the surfaces of antigen-presenting cells (APCs) and T cells, and modulate the ultimate magnitude and quality of T cell receptor (TCR) signaling. In the past 10 years, the field of co-signaling research has been advanced by the understanding of underlying mechanisms of the immune modulation led by newly identified co-signaling molecules and the successful preclinical and clinical trials targeting co-inhibitory molecules called immune checkpoints in the treatment of autoimmune diseases and cancers. In this review, we briefly describe the characteristics of well-known B7 co-signaling family members regarding the expression, functions and therapeutic implications and to introduce newly identified B7 members such as B7-H5, B7-H6, and B7-H7.

• IMMUNE NETWORK
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• v.22 no.5
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• pp.37.1-37.16
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• 2022

Autoimmune diseases are caused by a dysfunction of the acquired immune system. In a subset of autoimmune diseases, B cells escaping immune tolerance present autoantigen and produce cytokines and/or autoantibodies, resulting in systemic or organ-specific autoimmunity. Therefore, B cell depletion with monoclonal Abs targeting B cell lineage markers is standard care therapy for several B cell-mediated autoimmune disorders. In the last 5 years, genetically-engineered cellular immunotherapies targeting B cells have shown superior efficacy and long-term remission of B cell malignancies compared to historical clinical outcomes using B cell depletion with monoclonal Ab therapies. This has raised interest in understanding whether similar durable remission could be achieved with use of genetically-engineered cell therapies for autoimmunity. This review will focus on current human clinical trials using engineered cell therapies for B cell-associated autoimmune diseases.

• Biomolecules & Therapeutics
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• v.18 no.4
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• pp.463-468
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• 2010

T-cell activation depends on signals received by the T-cell receptor and CD28 co-stimulatory receptor. Since B7.1 and B7.2 molecules expressed on the surface of antigen presenting cells provide co-stimulatory signals through CD28 to T-cells, an inhibitor of CD28-B7.1/B7.2 binding has been proposed as a therapeutic agent for suppression of excessive T-cell activity. Although anti-B7.1/B7.2 antibodies are known to block B7.1 and B7.2 molecules, their effects on intracellular events in antigen presenting cells remain unclear. In this study, anti-B7.1/B7.2 antibodies decreased secretion of nitric oxide and pro-inflammatory cytokines such as TNF-$\alpha$, IL-$1{\beta}$, and IL-12 in LPS-activated RAW264.7 macrophage-like cells and peritoneal macrophages. Moreover, anti-B7.1/B7.2 antibodies inhibited $I{\kappa}B{\alpha}$ phosphorylation and down-regulated expression of co-stimulatory molecules including B7.1, B7.2, and PD-L1 in LPS-stimulated peritoneal macrophages. These findings suggest that CTLA4-Ig and anti-B7.1/B7.2 antibodies may be candidates to treat chronic inflammatory diseases and autoimmune responses caused by excessive activation of both T-cells and macrophages.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.3
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• pp.863-867
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• 2004

Herba Patriniae(HP) has been known to exert anti-inflammation and -tumoral activity in Korea. However, its molecular mechanism of action is not understood. In this study, we found that HP extract induced apoptosis in androgen-dependent prostate cancer LNCaP cells as evidenced by DNA fragmentation. Our data demonstrated that HP extract-induced apoptotic cell death was accompanied by inhibition of NF- κB activation, lowering effects of intracellular prostate specific antigen(PSA) and androgen reoeptor(AR) expression in a time dependent manner. Taken together, HP extract may inhibit the proliferation of prostate cancer LNCaP cell associated with inhibition of NF- κB activation, PSA and AR expression and that of apoptosis.

• Journal of Acupuncture Research
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• v.20 no.5
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• pp.50-62
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• 2003

Objective: Bee Venom(BV) has been used for various kinds of inflammatory or painful conditions in Oriental Medicine clinics, and there publishes reports on its therapeutic effects and the probable mechanism of those therapeutic effects, where CDs and cytokines plays important role. This study investigated the influences of bee venom on the expressions of CDs and cytokines of HMC cell line Methods: In this study we analysed the expression profile of HMC cell line treated with BV of 10-2ug/ml in relation to that of HMC cell line treated with vehicle by way of CD/cytokine microarray hybridization with 342 genes on it. Results: There were no upregulated genes by more than 3 fold, while there showed some downregulated genes by less than 1/3 fold as follows: colony stimulating factor 2, CD122, IL-7, CD112, TNF-alpha, CD138, CD166, TGFbetaR2, CD42b, CD62L, CD111, interleukin 10 receptor alpha, colony stimulating factor 1(macrophage), CD38 antigen(p45), CD121a, CD33 antigen(gp67), colony stimulating factor 1 receptor, B cell linker protein (SLP65) mRNA, CD94, alanyl(membrane) aminopeptidase, immunoglobulin(CD79A) binding protein 1, CD205, CD241, CD207, CDw121b, integrin alpha L(CD11a), integrin beta 1(CD29), CD91, CD42b. Conclusions: Bee venom treatment induced downregulation of some CDs or cytokines including $TNF-{\alpha}$. IL-1R with its possible implication in an antiinflammatory action of BV. Further research on expression profile changes induced by BV treatment is expected.

• Journal of Microbiology and Biotechnology
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• v.10 no.6
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• pp.844-850
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• 2000

The specific binding and internalization of viral particles is an essential step for the successful infection of viral pathogens. In the case of the hepatitis B virus (HBV), virions bind to the host cell via the preS domain of the viral surface antigen and are subsequently internalized by endocytosis. HBV-preS specific receptors are primarily expressed on hepatocytes, however, viral DNA and proteins have also been detected in extrahepatic sites, suggsting that celluar recepators for HBV may also exist on extrahepatic cells. Recently, an EBV-transformed B-cell line was identified onto which the preS region binds in a receptor-ligand specific manner. In this study, this specific interaction was further characterized, and the binding region within the preS protein was locaized. Also the internalization after host cell attachment was visualized and analyzed by fluorescence-labeled HBV-preS1 proteins using confocal microscopy. Energy depletion by sodium azide treatment effectively inhibited the internalization of the membrane-bound preS1 ligands, thereby indicating an energy-dependent receptor-mediated endocytotic pathway. Accordingly, the interaction of HBV-pres! with this specific B-cell line may serve as an effective model for an infection pathway in extrahepatic cells.

• IMMUNE NETWORK
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• v.16 no.4
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• pp.233-241
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• 2016

DCs, like the sensory neurons, express vanilloid receptor 1 (VR1). Here we demonstrate that the VR1 agonists, capsaicin (CP) and resiniferatoxin (RTX), enhance antiviral CTL responses by increasing MHC class I-restricted viral antigen presentation in dendritic cells (DCs). Bone marrow-derived DCs (BM-DCs) were infected with a recombinant vaccinia virus (VV) expressing OVA (VV-OVA), and then treated with CP or RTX. Both CP and RTX increased MHC class I-restricted presentation of virus-encoded endogenous OVA in BM-DCs. Oral administration of CP or RTX significantly increased MHC class I-restricted OVA presentation by splenic and lymph node DCs in VV-OVA-infected mice, as assessed by directly measuring OVA peptide SIINFEKL-K^b complexes on the cell surface and by performing functional assays using OVA-specific CD8 T cells. Accordingly, oral administration of CP or RTX elicited potent OVA-specific CTL activity in VV-OVA-infected mice. The results from this study demonstrate that VR1 agonists enhance anti-viral CTL responses, as well as a neuro-immune connection in anti-viral immune responses.

• Journal of Veterinary Clinics
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• v.26 no.5
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• pp.419-422
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• 2009

We performed the PARR (PCR to detect antigen receptor rearrangements) test on DNA isolated from twelve archival canine cytological slides including nine lymphoma, two reactive lymphocytes and one sample from Ehrlichia canis infected dog. As a result, our PCR control gene, $C{\mu}$, was successfully amplified from all of the DNA samples. Six out of nine lymphoma samples showed a clonal rearrangement of immunoglobulin gene whereas three samples did a clonal rearrangement of T cell receptor gamma ($TCR{\gamma}$) gene. However, we observed no visible or clear bands from PCR conducted using our antigen receptor rearrangement primers on DNA from a reactive lymphoid cell proliferation used as a negative control. False-positive amplification in $TCR{\gamma}$ gene was observed only in one sample from E. canis infection. The use of archival cytological specimens demonstrated in this study offers potential advantages for cost-effective specimen acquisition and efficient high-fidelity DNA analysis.