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Guo Z, Wang J, Meng L, Wu Q, Kim O, Hart J, He G, Zhou P, Thistlethwaite JR, Alegre ML, Fu YX, Newell KA. Cutting edge: membrane lymphotoxin regulates CD8(+) T cell-mediated intestinal allograft rejection. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 167:4796-800. [PMID: 11673481 DOI: 10.4049/jimmunol.167.9.4796] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Blocking the CD28/B7 and/or CD154/CD40 costimulatory pathways promotes long-term allograft survival in many transplant models where CD4(+) T cells are necessary for rejection. When CD8(+) T cells are sufficient to mediate rejection, these approaches fail, resulting in costimulation blockade-resistant rejection. To address this problem we examined the role of lymphotoxin-related molecules in CD8(+) T cell-mediated rejection of murine intestinal allografts. Targeting membrane lymphotoxin by means of a fusion protein, mAb, or genetic mutation inhibited rejection of intestinal allografts by CD8(+) T cells. This effect was associated with decreased monokine induced by IFN-gamma (Mig) and secondary lymphoid chemokine (SLC) gene expression within allografts and spleens respectively. Blocking membrane lymphotoxin did not inhibit rejection mediated by CD4(+) T cells. Combining disruption of membrane lymphotoxin and treatment with CTLA4-Ig inhibited rejection in wild-type mice. These data demonstrate that membrane lymphotoxin is an important regulatory molecule for CD8(+) T cells mediating rejection and suggest a strategy to avoid costimulation blockade-resistant rejection.
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Chen R, Kim O, Yang J, Sato K, Eisenmann KM, McCarthy J, Chen H, Qiu Y. Regulation of Akt/PKB activation by tyrosine phosphorylation. J Biol Chem 2001; 276:31858-62. [PMID: 11445557 DOI: 10.1074/jbc.c100271200] [Citation(s) in RCA: 195] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Activation of Akt/PKB by growth factors requires multiple phosphorylation events. Phosphorylation of Thr(308) and Ser(473) of Akt by its upstream kinase(s) or autophosphorylation is critical for optimal activation of its kinase activity. Here, we present evidence that tyrosine phosphorylation is required for Akt activation. Epidermal growth factor treatment induces tyrosine phosphorylation of Akt in COS1 and PC3M cells, which is abrogated by PP2, a selective inhibitor for Src family tyrosine kinases. Elevated Akt activity is observed in v-Src transformed NIH3T3 cells, which is accompanied with increased tyrosine phosphorylation of Akt. Akt activity induced by growth factors is significantly reduced in SYF cells lacking Src, Yes, and Fyn, which can be restored by introducing c-Src, but not the kinase-inactive Src, back to these cells. Furthermore, we have identified two tyrosine residues near the activation loop of Akt that are important for its activation. Substitution of these residues with phenylalanine abolishes Akt kinase activity stimulated by growth factors. These two YF mutants fail to block Forkhead transcription factor activity in 293 cells and are unable to prevent apoptosis induced by matrix detachment. Our data suggest that, in addition to phosphorylation of Thr(308) and Ser(473), tyrosine phosphorylation of Akt may be essential for its biological function.
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Kim O. Immunohistochemical study of the expression of alpha-smooth muscle actin and the proliferation marker Ki-67 of glomerulonephritis. J Korean Med Sci 2001; 16:455-61. [PMID: 11511791 PMCID: PMC3054781 DOI: 10.3346/jkms.2001.16.4.455] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The aim of this study was to determine the relationship of alpha-smooth muscle actin (ASMA) and the proliferation marker Ki-67 of glomerulonephritis (GN). Immunohistochemical stainings with the usual streptavidin-biotin peroxidase method were performed on 86 renal biopsies using monoclonal 1A4 and Ki-67. The results of the quantitative evaluation of ASMA and Ki-67 were analyzed for the correlation between positive value of ASMA and Ki-67 in different GN. ASMA expressions of glomeruli were highest in acute post-infectious GN [APGN; 16.9 Fraction Volume (FV)%], followed by unclassified proliferative GN (UnGN; 12.5 FV%), membranoproliferative GN (MPGN; 8.5 FV%), lupus nephritis (LupusN; 6.3 FV%), IgA nephritis (IgAN; 5.6 FV%), and normal control (0.1 FV%). The Ki-67 staining was considerably elevated in lupusN (4.3 Ki-67 positives/glomerulus), APGN (2.7), MPGN (2.5), UnGN (1.66), IgAN (0.5), compared with that in normal control group (0.1 Ki-67 positives/glomerulus). Ki-67 value in each category of glomerular diseases was significantly different from that in the control biopsies (p<0.004). The relationship between morphometric results of ASMA and Ki-67 was statistically significant regardless of the diagnosis. (rs=0.425, p=0.000, ASMA= 0.1113+0.1665 Ki-67). In conclusion, the immunohistochemical assessment of ASMA and Ki-67 expression in GN might be a reliable indicator for the progression of GN. This study indicates that active cellular proliferation is associated with increased actin deposition in glomeruli.
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Abstract
This study examined the sex differences in reports of social support (network size and satisfaction), loneliness, and depression among Korean college students and examined whether measures of social support and loneliness predicted depression scores. In the sample were 452 college students enrolled in four universities in Korea. The women reported a larger social support network size and being less satisfied with their support than the men. Women reported higher scores on the Revised UCLA Loneliness Scale and the Beck Depression Inventory than men. Social support satisfaction scores and network size on the Social Support Questionnaire-6 and scores on the Loneliness Scale predicted scores on Depression in both the groups. Loneliness was the largest predictor of Depression for either sex. The amount of variance in Depression accounted for by Loneliness was 35% for women and 24% for men.
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Guo Z, Meng L, Kim O, Wang J, Hart J, He G, Alegre ML, Thistlethwaite JR, Pearson TC, Larsen CP, Newell KA. CD8 T cell-mediated rejection of intestinal allografts is resistant to inhibition of the CD40/CD154 costimulatory pathway. Transplantation 2001; 71:1351-4. [PMID: 11403253 DOI: 10.1097/00007890-200105150-00033] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
BACKGROUND Disruption of the CD40/CD154 pathway inhibits rejection in numerous models. The importance of this pathway on intestinal allograft rejection was examined in this study. METHODS Intestinal grafts from B6C3F1 mice transplanted into C57BL/6 recipients were assessed histologically for rejection. RESULTS The monoclonal antibody to CD154, MR1, failed to inhibit rejection in wild-type mice. Similarly, CD154-/- recipient mice rejected intestinal allografts. MR1 did inhibit early rejection in CD8-/- mice, but had no effect in CD4-/- recipients. All MR1-treated CD8-/- recipients eventually developed rejection. No benefit was observed when blockade of the CD40/CD154 pathway by MR1 was combined with blockade of the CD28/B7 pathway by mCTLA4Ig. CONCLUSIONS These data suggest that CD4+ T cells mediating intestinal allograft rejection may be more dependent upon the CD40/CD154 pathway than CD8+ T cells. This finding highlights the importance of identifying agents that suppress CD8+ T cell-mediated rejection.
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Chen R, Kim O, Li M, Xiong X, Guan JL, Kung HJ, Chen H, Shimizu Y, Qiu Y. Regulation of the PH-domain-containing tyrosine kinase Etk by focal adhesion kinase through the FERM domain. Nat Cell Biol 2001; 3:439-44. [PMID: 11331870 DOI: 10.1038/35074500] [Citation(s) in RCA: 117] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Etk/BMX, a member of the Btk family of tyrosine kinases, is highly expressed in cells with great migratory potential, including endothelial cells and metastatic carcinoma cell lines. Here, we present evidence that Etk is involved in integrin signalling and promotes cell migration. The activation of Etk by extracellular matrix proteins is regulated by FAK through an interaction between the PH domain of Etk and the FERM domain of FAK. The lack of Etk activation by extracellular matrix in FAK-null cells could be restored by co-transfection with wild-type FAK. Disrupting the interaction between Etk and FAK diminished the cell migration promoted by either kinase. Furthermore, inhibiting Etk expression in metastatic carcinoma cell lines with an antisense oligonucleotide blocks integrin-mediated migration of these cells. Taken together, our data indicate the essential role of the interaction of the PH domain of Etk and the FERM domain of FAK in integrin signalling.
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Szot GL, Zhou P, Rulifson I, Wang J, Guo Z, Kim O, Newel KA, Thistlethwaite JR, Bluestone JA, Alegre ML. Different mechanisms of cardiac allograft rejection in wildtype and CD28-deficient mice. Am J Transplant 2001; 1:38-46. [PMID: 12095035 DOI: 10.1034/j.1600-6143.2001.010108.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Although CD28 blockade results in long-term cardiac allograft survival in wildtype mice, CD28-deficient mice effectively reject heart allografts. This study compared the mechanisms of allogeneic responses in wildtype and CD28-deficient mice. Adoptive transfer of purified CD28-deficient T cells into transplanted nude mice resulted in graft rejection. However, this model demonstrated that the allogeneic T cell function was severely impaired when compared with wildtype T cells, despite similar survival kinetics. Cardiac allograft rejection depended on both CD4+ and CD8+ T cell subsets in CD28-deficient mice, whereas only CD4+ T cells were necessary in wildtype recipients. These results suggested that CD8+ T cells were more important in CD28-deficient than wildtype mice. In addition to the CD8+ T cell requirement, allograft rejection in CD28-deficient mice was dependent on a sustained presence of CD4+ T cells, whereas it only required the initial presence of CD4+ T cells in wildtype mice. Taken together, these data suggest that CD4+ T cells from CD28-deficient mice have impaired responses to alloantigen in vivo, thus requiring long-lasting cooperation with CD8+ T cell responses to facilitate graft rejection. These results may help to explain the failure to promote graft tolerance in some preclinical and clinical settings.
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33
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Quinn A, McInerney B, Reich EP, Kim O, Jensen KP, Sercarz EE. Regulatory and effector CD4 T cells in nonobese diabetic mice recognize overlapping determinants on glutamic acid decarboxylase and use distinct V beta genes. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 166:2982-91. [PMID: 11207247 DOI: 10.4049/jimmunol.166.5.2982] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The 524--543 region of glutamic acid decarboxylase (GAD65), GAD65(524--543), is one of the first fragments of this islet Ag to induce proliferative T cell responses in the nonobese diabetic (NOD) mouse model of spontaneous autoimmune diabetes. Furthermore, NOD mice given tolerogenic doses of GAD65(524--543) are protected from spontaneous and cyclophosphamide-induced diabetes. In this study, we report that there are at least two I-A(g7)-restricted determinants present in the GAD65(524--543) sequence, each capable of recruiting unique T cell repertoires characterized by distinct TCR V beta gene use. CD4(+) T cells arise spontaneously in young NOD mice to an apparently dominant determinant found within the GAD65 peptide 530--543 (p530); however, T cells to the overlapping determinant 524-538 (p524) dominate the response only after immunization with GAD65(524--543). All p530-responsive T cells used the V beta 4 gene, whereas the V beta 12 gene is preferentially used to encode the TCR of p524-responsive T cell populations. T cell clones and hybridomas from both of these T cell groups were responsive to APC pulsed with GAD65(524--543) or whole rGAD65. p524-reactive cells appeared to be regulatory upon adoptive transfer into young NOD mice and could inhibit insulin-dependent diabetes mellitus development, although they were unable to produce IL-4, IL-10, or TGF beta upon antigenic challenge. Furthermore, we found that i.p. injection with p524/IFA was very effective in providing protection from cyclophosphamide-induced insulin-dependent diabetes mellitus. These data demonstrate that the regulatory T cells elicited by immunizing with GAD65(524--543) are unique and distinct from those that arise from spontaneous endogenous priming, and that T cells to this limited region of GAD65 may be either regulatory or pathogenic.
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MESH Headings
- Adoptive Transfer
- Amino Acid Motifs/genetics
- Amino Acid Motifs/immunology
- Amino Acid Sequence
- Animals
- CD4-Positive T-Lymphocytes/immunology
- CD4-Positive T-Lymphocytes/metabolism
- CD4-Positive T-Lymphocytes/transplantation
- Cell Line
- Clone Cells
- Diabetes Mellitus, Type 1/immunology
- Diabetes Mellitus, Type 1/prevention & control
- Epitopes, T-Lymphocyte/immunology
- Female
- Gene Rearrangement, beta-Chain T-Cell Antigen Receptor
- Genes, T-Cell Receptor beta
- Glutamate Decarboxylase/administration & dosage
- Glutamate Decarboxylase/immunology
- Glutamate Decarboxylase/metabolism
- Hybridomas
- Injections, Subcutaneous
- Isoenzymes/administration & dosage
- Isoenzymes/immunology
- Isoenzymes/metabolism
- Lymphocyte Activation/genetics
- Mice
- Mice, Inbred BALB C
- Mice, Inbred NOD
- Molecular Sequence Data
- Peptide Fragments/administration & dosage
- Peptide Fragments/genetics
- Peptide Fragments/immunology
- Receptors, Antigen, T-Cell, alpha-beta/biosynthesis
- Receptors, Antigen, T-Cell, alpha-beta/deficiency
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- Tumor Cells, Cultured
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34
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Meng L, Guo Z, Kim O, He G, Hart J, Szot GL, Wang J, Pearson TC, Larsen CP, Newell KA. Blockade of the CD40 pathway fails to prevent CD8 T cell-mediated intestinal allograft rejection. Transplant Proc 2001; 33:418-20. [PMID: 11266891 DOI: 10.1016/s0041-1345(00)02075-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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35
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Zhou P, Szot G, Guo Z, Kim O, He G, Wang J, Grusby M, Newell K, Thistlethwaite J, Bluestone J, Alegre M. Role of STAT6 signaling in the induction and long-term maintenance of tolerance mediated by CTLA4-Ig. Transplant Proc 2001; 33:214-6. [PMID: 11266784 DOI: 10.1016/s0041-1345(00)01979-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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36
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Chae C, Kim O, Choi C, Min K, Cho WS, Kim J, Tai JH. Prevalence of porcine epidemic diarrhoea virus and transmissible gastroenteritis virus infection in Korean pigs. Vet Rec 2000; 147:606-8. [PMID: 11110482 DOI: 10.1136/vr.147.21.606] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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37
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Zhou P, Szot GL, Guo Z, Kim O, He G, Wang J, Grusby MJ, Newell KA, Thistlethwaite JR, Bluestone JA, Alegre ML. Role of STAT4 and STAT6 signaling in allograft rejection and CTLA4-Ig-mediated tolerance. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2000; 165:5580-7. [PMID: 11067913 DOI: 10.4049/jimmunol.165.10.5580] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
STAT4(-/-) mice have impaired type 1 T cell differentiation, whereas STAT6(-/-) mice fail to generate type 2 responses. The role of type 1 and type 2 T cell differentiation in acute cardiac allograft rejection and in the induction of tolerance was examined in wild-type, STAT4(-/-), and STAT6(-/-) recipients. All recipients rejected the grafts promptly. Analysis of in situ cytokine gene expression in the allografts confirmed decreased levels of IFN-gamma in STAT4(-/-) recipients and undetectable levels of IL-4 and IL-5 in STAT6(-/-) mice. Blockade of the CD28/B7 costimulatory pathway prolonged cardiac graft survival for >100 days in 100% of wild-type and STAT4(-/-) mice. However, 14% of CTLA4-Ig-treated STAT6(-/-) mice rejected their grafts between 20 and 100 days. Moreover, of those animals followed past 100 days, 60% of the STAT6(-/-) mice rejected their grafts. Splenocytes harvested on day 145 posttransplant from CTLA4-Ig-treated rejecting STAT6(-/-) recipients were transfused into syngeneic SCID mice transplanted with donor or third party cardiac allografts. Both donor and third party grafts were rejected, indicating that the initial graft loss may be due to an immunological rejection. In contrast, when splenocytes from CTLA4-Ig-treated wild-type or nonrejecting STAT6(-/-) mice were transferred into SCID recipients, donor allografts were accepted, but third party hearts were rejected. Thus, long-term prolongation of cardiac allograft survival by CTLA4-Ig is STAT4-independent but, at least in part, STAT6-dependent. These data suggest that the balance of type 1 and type 2 T lymphocyte differentiation is not critical for acute rejection but influences the robust tolerance induced by CD28/B7 blockade in this model.
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MESH Headings
- Abatacept
- Acute Disease
- Adoptive Transfer
- Animals
- Antigens, CD
- Antigens, Differentiation/administration & dosage
- Antigens, Differentiation/physiology
- CTLA-4 Antigen
- DNA-Binding Proteins/deficiency
- DNA-Binding Proteins/genetics
- DNA-Binding Proteins/physiology
- Graft Enhancement, Immunologic/methods
- Graft Rejection/genetics
- Graft Rejection/immunology
- Graft Rejection/prevention & control
- Graft Survival/genetics
- Graft Survival/immunology
- Heart Transplantation/immunology
- Immune Tolerance/genetics
- Immune Tolerance/immunology
- Immunoconjugates
- Injections, Intraperitoneal
- Interferon-gamma/biosynthesis
- Interferon-gamma/genetics
- Lymphocyte Transfusion
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C3H
- Mice, Inbred C57BL
- Mice, Knockout
- Mice, SCID
- RNA, Messenger/biosynthesis
- STAT4 Transcription Factor
- STAT6 Transcription Factor
- Signal Transduction/genetics
- Signal Transduction/immunology
- Spleen/cytology
- Spleen/transplantation
- T-Lymphocytes/transplantation
- Trans-Activators/deficiency
- Trans-Activators/genetics
- Trans-Activators/physiology
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Abstract
A total of 446 serum samples from 88 herds in Korea were examined for antibody to porcine respiratory coronavirus (PRCV) using blocking enzyme-linked immunosorbent assay (ELISA). All serum samples were collected from 24- to 26-week-old finishing pigs between December 1998 and June 1999. By ELISA, 237 out of 446 sera tested (53.1%) and 54 out of 88 sampled herds (61.3%) were positive against PRCV. Of 446 sera from 88 herd tested, 185 (41.5%) serum samples from 22 (25%) herds were seronegative against PRCV and transmissible gastroenteritis virus infection. Our data suggested that seropositive herds for PRCV are distributed diffusely throughout South Korea.
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39
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Turk E, Kim O, le Coutre J, Whitelegge JP, Eskandari S, Lam JT, Kreman M, Zampighi G, Faull KF, Wright EM. Molecular characterization of Vibrio parahaemolyticus vSGLT: a model for sodium-coupled sugar cotransporters. J Biol Chem 2000; 275:25711-6. [PMID: 10835424 DOI: 10.1074/jbc.m003127200] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The Na(+)/galactose cotransporter (vSGLT) of Vibrio parahaemolyticus, tagged with C-terminal hexahistidine, has been purified to apparent homogeneity by Ni(2+) affinity chromatography and gel filtration. Resequencing the vSGLT gene identified an important correction: the N terminus constitutes an additional 13 functionally essential residues. The mass of His-tagged vSGLT expressed under its native promoter, as determined by electrospray ionization-mass spectrometry (ESI-MS), verifies these 13 residues in wild-type vSGLT. A fusion protein of vSGLT and green fluorescent protein, comprising a mass of over 90 kDa, was also successfully analyzed by ESI-MS. Reconstitution of purified vSGLT yields proteoliposomes active in Na(+)-dependent galactose uptake, with sugar preferences (galactose > glucose > fucose) reflecting those of wild-type vSGLT in vivo. Substrates are transported with apparent 1:1 stoichiometry and apparent K(m) values of 129 mm (Na(+)) and 158 microm (galactose). Freeze-fracture electron microscopy of functional proteoliposomes shows intramembrane particles of a size consistent with vSGLT existing as a monomer. We conclude that vSGLT is a suitable model for the study of sugar cotransporter mechanisms and structure, with potential applicability to the larger SGLT family of important sodium:solute cotransporters. It is further demonstrated that ESI-MS is a powerful tool for the study of proteomics of membrane transporters.
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40
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Kim B, Kim O, Tai JH, Chae C. Transmissible gastroenteritis virus induces apoptosis in swine testicular cell lines but not in intestinal enterocytes. J Comp Pathol 2000; 123:64-6. [PMID: 10906258 DOI: 10.1053/jcpa.2000.0386] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Evidence of apoptosis caused by infection with the Purdue strain of transmissible gastroenteritis virus (TGEV) was sought in vitro (in infected swine testicular [ST] cells) and in vivo (in the intestinal tissues of infected piglets). The methods used were (1) DNA electrophoresis for detection of DNA fragmentation, and (2) terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-fluorescein nick and labelling (TUNEL). DNA "laddering" was detected in TGEV-infected ST cells only. Numerous signs of apoptosis were detected in TGEV-infected ST cells by TUNEL assay, the positive (dark brown) staining reaction being present in the majority of cell nuclei, without background staining. No such staining was seen in TGEV-infected enterocytes at various times after inoculation of piglets. Thus, it would appear that apoptosis does not occur in the enterocytes of piglets infected with TGEV.
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41
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Kim O, Choi C, Kim B, Chae C. Detection and differentiation of porcine epidemic diarrhoea virus and transmissible gastroenteritis virus in clinical samples by multiplex RT-PCR. Vet Rec 2000; 146:637-40. [PMID: 10872784 DOI: 10.1136/vr.146.22.637] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
A multiplex reverse-transcriptase-PCR (RT-PCR) procedure was developed for the simultaneous detection of porcine epidemic diarrhoea virus (PEDV) and transmissible gastroenteritis virus (TGEV) in preweaning pigs with diarrhoea. The membrane gene of PEDV and the nucleocapsid gene of TGEV were chosen as targets. The PCR products of PEDV and TGEV had molecular sizes of 412 and 612 base pairs, respectively. Primers from PEDV did not react with any TGEV tested and vice versa. In addition, the primers did not react with other pig viruses. The multiplex RT-PCR was able to detect 10 tissue culture-infective doses 50 per cent (TCID50)/ml of PEDV or TGEV with each of the primer sets for PEDV and TGEV, respectively. The RNAS of PEDV and TGEV were detected directly in intestinal and faecal samples from pigs infected experimentally with either virus. The results of the assay correlated well with the results of virus isolation. None of the five control specimens was positive. PEDV was detected in 10 intestinal and nine faecal samples, and among the nine positive faecal samples two were culture-negative. TGEV was also detected in 10 intestinal and nine faecal samples, and among the nine positive faecal samples, three were culture-negative.
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42
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Szot GL, Zhou P, Sharpe AH, He G, Kim O, Newell KA, Bluestone JA, Thistlethwaite JR. Absence of host B7 expression is sufficient for long-term murine vascularized heart allograft survival. Transplantation 2000; 69:904-9. [PMID: 10755548 DOI: 10.1097/00007890-200003150-00040] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
CD28 antagonists have been shown to promote long-term graft survival and induce donor-specific tolerance. In this study, the role of CD28/B7 costimulation and the relative importance of host versus donor B7 expression in allograft rejection was assessed in a murine abdominal vascularized heterotopic heart transplant model. Wild-type, CD28-deficient, or B7-1/B7-2-deficient C57BL/6 (B6) mice were grafted with allogeneic wild type or B7-1/B7-2-deficient hearts. The results demonstrate allogeneic heart grafts survive long-term in mCTLA4Ig-treated B6 and untreated B7-1/B7-2-deficient B6 recipients but not CD28KO B6 mice. B7-1/B7-2KO B6 recipients treated with anti-CD28 (PV-1) or recombinant human IL-2 rejected the heart transplants indicating that these mice are immunologically competent to reject grafts if costimulatory signals are supplied or bypassed. Finally, there was no difference in rejection between normal animals transplanted with wild-type versus B7-1/B7-2-deficient hearts. These results support a critical role for B7-expressing host antigen presenting cells in the rejection of heart allografts in mice and differences among B7KO and CD28KO animals.
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43
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Kim O, Chae C. In situ hybridization for the detection and localization of porcine epidemic diarrhea virus in the intestinal tissues from naturally infected piglets. Vet Pathol 2000; 37:62-7. [PMID: 10643982 DOI: 10.1354/vp.37-1-62] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Detection and localization of porcine epidemic diarrhea virus (PEDV) was studied by in situ hybridization with a nonradioactive digoxigenin-labeled probe in formalin-fixed, paraffin-embedded tissues from 10 naturally infected piglets. A 377-base pair cDNA probe for viral RNA encoding the membrane proteins of PEDV cell-culture-adapted strain V215/78 was generated by the reverse transcription polymerase chain reaction. In the retrospective study of pigs from herds with diarrhea, the 10 piglets naturally infected with PEDV had positive signals for PEDV by in situ hybridization. When intestinal tissues were hybridized with the PEDV probe, a strong signal was seen in the villus enterocytes of jejunum and ileum but not in the cecum and colon. Positive cells typically had dark brown reaction products in the cytoplasm. Scattered epithelial cells along the ileal Peyer's patches dome areas contained viral RNA. In one piglet, hybridization signal was also found in the duodenum. PEDV was not demonstrated in tissues outside of the intestinal tract. These findings indicate that jejunal and ileal villus enterocytes are the main target of PEDV replication during epizootic outbreaks of the disease.
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44
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Kim O, Chae C. Application of reverse transcription polymerase chain reaction to detect porcine epidemic diarrhea virus in Vero cell culture. J Vet Diagn Invest 1999; 11:537-8. [PMID: 12968738 DOI: 10.1177/104063879901100610] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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45
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Camuffo D, Brimblecombe P, Van Grieken R, Busse HJ, Sturaro G, Valentino A, Bernardi A, Blades N, Shooter D, De Bock L, Gysels K, Wieser M, Kim O. Indoor air quality at the Correr Museum, Venice, Italy. THE SCIENCE OF THE TOTAL ENVIRONMENT 1999; 236:135-52. [PMID: 10535149 DOI: 10.1016/s0048-9697(99)00262-4] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/13/2023]
Abstract
Two multidisciplinary field surveys, one in winter and the other in summer have monitored the indoor microclimate, air pollution, deposition and origin of the suspended particulate matter and microorganisms of the Correr Museum, Venice. In addition, this study was focused to identify the problems caused by the heating and air conditioning system (HAC) and the effects due to the presence of carpets. Heating and air conditioning systems (HACs), when chiefly designed for human welfare, are not suitable for conservation and can cause dangerous temperature and humidity fluctuations. Improvements at the Correr Museum have been achieved with the assistance of environmental monitoring. The carpet has a negative influence as it retains particles and bacteria which are resuspended each time people walk on it. The indoor/outdoor pollutants ratio is greater in the summertime, when doors and windows are more frequently open to allow for better ventilation, illustrating that this ratio is mainly governed by the free exchange of the air masses. The chemical composition, size and origin of the suspended particulate matter have been identified, as well as the bacteria potentially dangerous to the paintings. Some general suggestions for improving indoor air quality are reported in the conclusions.
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Kim O, Chae C, Kweon CH. Monoclonal antibody-based immunohistochemical detection of porcine epidemic diarrhea virus antigen in formalin-fixed, paraffin-embedded intestinal tissues. J Vet Diagn Invest 1999; 11:458-62. [PMID: 12968761 DOI: 10.1177/104063879901100512] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
An immunohistochemistry technique was developed for the diagnosis of porcine epidemic diarrhea virus (PEDV). The technique was tested on formalin-fixed, paraffin-embedded intestinal tissues from piglets naturally infected with PEDV. Five different monoclonal antibodies (MAbs) were tested in this study. PEDV antigen was consistently detected in the PLP (4% paraformaldehyde, 100 mM L-lysine dihydrochloride, 10 mM sodium m-periodate in phosphate-buffered saline)-fixed PEDV-infected Vero cells or formalin-fixed, paraffin-embedded intestinal tissues from piglets naturally infected with PEDV. The C9-2-2 MAb gave the strongest reactivity and least background staining, detecting 10 of 10 infected pigs. The positive reaction was cytoplasmic. Positive enterocytes were distributed over the tip and along the sides of atrophied or fused villi in the jejunum and ileum. Positive-staining cells were not detected in the crypts. No staining was observed in cecum and colon. No positive cells were observed when the C9-2-2 MAb was reacted with the tissue sections from noninfected piglets or from transmissible gastroenteritus virus (TGEV)- and rotavirus-infected piglets. The selected anti-PEDV MAbs tested on formalin-fixed, paraffin-embedded tissue sections are useful for diagnosis when virus isolation is not available. This method would be of particular value in countries where both PEDV and TGEV are epizootic and would aid in differentiating between PEDV and TGEV infection.
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Newell KA, He G, Guo Z, Kim O, Szot GL, Rulifson I, Zhou P, Hart J, Thistlethwaite JR, Bluestone JA. Cutting edge: blockade of the CD28/B7 costimulatory pathway inhibits intestinal allograft rejection mediated by CD4+ but not CD8+ T cells. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1999; 163:2358-62. [PMID: 10452966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
The effect of blocking the CD28/B7 costimulatory pathway on intestinal allograft rejection was examined in mice. Murine CTLA4Ig failed to prevent the rejection of allografts transplanted into wild-type or CD4 knockout (KO) mice but did inhibit allograft rejection by CD8 KO recipients. This effect was associated with decreased intragraft mRNA for IFN-gamma and TNF-alpha and increased mRNA for IL-4 and IL-5. This altered pattern of cytokine production was not observed in allografts from murine CTLA4Ig-treated CD4 KO mice. These data demonstrate that blockade of the CD28/B7 pathway has different effects on intestinal allograft rejection mediated by CD4+ and CD8+ T cells and suggest that these T cell subsets have different costimulatory requirements in vivo. The results also suggest that the inhibition of CD4+ T cell-mediated allograft rejection by CTLA4Ig may be related to down-regulation of Th1 cytokines and/or up-regulation of Th2 cytokines.
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Brimblecombe P, Blades N, Camuffo D, Sturaro G, Valentino A, Gysels K, Van Grieken R, Busse HJ, Kim O, Ulrych U, Wieser M. The indoor environment of a modern museum building, the Sainsbury Centre for Visual Arts, Norwich, UK. INDOOR AIR 1999; 9:146-164. [PMID: 10439553 DOI: 10.1111/j.1600-0668.1999.t01-1-00002.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A multi-disciplinary approach was used to investigate the indoor environment of a modern museum building, and its suitability for the conservation of the collection therein. Climate, gaseous and particulate pollution and the concentrations of bacteria were measured in summer and winter campaigns. While the environment overall was found to be an acceptable one, a number of drawbacks were highlighted, the most serious of these being the large temperature and humidity fluctuations that occurred in the summer.
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Abstract
The purpose of this study was to examine the predictors of loneliness in elderly Korean immigrant women. The sample was derived from a larger study designed to examine loneliness in elderly Korean immigrants. Subjects were 110 elderly Korean immigrant women who were at least 60 years of age and lived in a large metropolitan city area in the United States of America. Data were collected by telephone interview using the Revised University of California Los Angeles (UCLA) Loneliness Scale (RULS), Social Support Questionnaire, Ethnic Attachment Questionnaire and Instrumental Activities of Daily Living (ADL) Scale. Measures were prepared using translation and back-translation procedures. Results indicate that elderly Korean immigrant women were more lonely than those found in other studies. Satisfaction with social support, social network size, ethnic attachment and functional status were predictive variables of loneliness. Satisfaction with social support was the largest predictor of loneliness in elderly Korean women. Marital status was not a predictor of loneliness.
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Abstract
The purpose of the study was to investigate the mediating effect of two types of social support (emotional and tangible support) between ethnic attachment and loneliness in older Korean immigrants. Emotional and tangible social support had three components; network size, network composition, and satisfaction with network members. The sample consisted of 174 older Korean immigrants who lived in a metropolitan area. Telephone interviews were used to collect data using translated Korean versions of the Revised UCLA Loneliness Scale, Ethnic Attachment Questionnaire, and the Revised Social Support Questionnaire. Emotional and tangible social support network size and satisfaction mediated the effect of ethnic attachment on loneliness. Older Koreans who had stronger ethnic attachment had more emotional and tangible supports, were more satisfied with their supports, and had a lower level of loneliness. Emotional and tangible social network composition did not serve as mediators in this study.
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