메뉴 건너뛰기




Volumn 47, Issue 11-12, 2010, Pages 2103-2111

Differential activation and maturation of two porcine DC populations following TLR ligand stimulation

Author keywords

Activation and maturation; Blood derived dendritic cells; Chemokines; Monocyte derived dendritic cells; Pig

Indexed keywords

B7 ANTIGEN; CD86 ANTIGEN; CHEMOKINE RECEPTOR CCR2; CHEMOKINE RECEPTOR CCR5; CHEMOKINE RECEPTOR CCR7; CPG OLIGODEOXYNUCLEOTIDE; CYTOKINE; INTERLEUKIN 12P40; INTERLEUKIN 6; LIPOPOLYSACCHARIDE; TOLL LIKE RECEPTOR; TUMOR NECROSIS FACTOR ALPHA;

EID: 77953611231     PISSN: 01615890     EISSN: None     Source Type: Journal    
DOI: 10.1016/j.molimm.2010.03.016     Document Type: Article
Times cited : (24)

References (53)
  • 1
    • 0034927083 scopus 로고    scopus 로고
    • Protection of BALB/c mice against Brucella abortus 544 challenge by vaccination with bacterioferritin or P39 recombinant proteins with CpG oligodeoxynucleotides as adjuvant
    • Al-Mariri A., Tibor A., Mertens P., De Bolle X., Michel P., Godefroid J., Walravens K., Letesson J.J. Protection of BALB/c mice against Brucella abortus 544 challenge by vaccination with bacterioferritin or P39 recombinant proteins with CpG oligodeoxynucleotides as adjuvant. Infect. Immun. 2001, 69:4816-4822.
    • (2001) Infect. Immun. , vol.69 , pp. 4816-4822
    • Al-Mariri, A.1    Tibor, A.2    Mertens, P.3    De Bolle, X.4    Michel, P.5    Godefroid, J.6    Walravens, K.7    Letesson, J.J.8
  • 2
    • 34248185036 scopus 로고    scopus 로고
    • Toll-like receptor 7 and MyD88 knockdown by lentivirus-mediated RNA interference to porcine dendritic cell subsets
    • Alves M.P., Neuhaus V., Guzylack-Piriou L., Ruggli N., McCullough K.C., Summerfield A. Toll-like receptor 7 and MyD88 knockdown by lentivirus-mediated RNA interference to porcine dendritic cell subsets. Gene Ther. 2007, 14:836-844.
    • (2007) Gene Ther. , vol.14 , pp. 836-844
    • Alves, M.P.1    Neuhaus, V.2    Guzylack-Piriou, L.3    Ruggli, N.4    McCullough, K.C.5    Summerfield, A.6
  • 4
    • 0033536062 scopus 로고    scopus 로고
    • CCR5(+) and CXCR3(+) T cells are increased in multiple sclerosis and their ligands MIP-1alpha and IP-10 are expressed in demyelinating brain lesions
    • Balashov K.E., Rottman J.B., Weiner H.L., Hancock W.W. CCR5(+) and CXCR3(+) T cells are increased in multiple sclerosis and their ligands MIP-1alpha and IP-10 are expressed in demyelinating brain lesions. Proc. Natl. Acad. Sci. U.S.A. 1999, 96:6873-6878.
    • (1999) Proc. Natl. Acad. Sci. U.S.A. , vol.96 , pp. 6873-6878
    • Balashov, K.E.1    Rottman, J.B.2    Weiner, H.L.3    Hancock, W.W.4
  • 8
    • 17544382774 scopus 로고    scopus 로고
    • Double-stranded secondary structures on mRNA induce type I interferon (IFN alpha/beta) production and maturation of mRNA-transfected monocyte-derived dendritic cells
    • Ceppi M., Ruggli N., Tache V., Gerber H., McCullough K.C., Summerfield A. Double-stranded secondary structures on mRNA induce type I interferon (IFN alpha/beta) production and maturation of mRNA-transfected monocyte-derived dendritic cells. J. Gene Med. 2005, 7:452-465.
    • (2005) J. Gene Med. , vol.7 , pp. 452-465
    • Ceppi, M.1    Ruggli, N.2    Tache, V.3    Gerber, H.4    McCullough, K.C.5    Summerfield, A.6
  • 9
    • 77951024349 scopus 로고    scopus 로고
    • Toll-like receptor expressions in porcine alveolar macrophages and dendritic cells in responding to poly IC stimulation and porcine reproductive and respiratory syndrome virus (PRRSV) infection
    • Epub 2008 Nov 12
    • Chaung H.C., Chen C.W., Hsieh B.L., Chung W.B. Toll-like receptor expressions in porcine alveolar macrophages and dendritic cells in responding to poly IC stimulation and porcine reproductive and respiratory syndrome virus (PRRSV) infection. Comp. Immunol. Microbiol. Infect. Dis. 2010, 33(3):197-213. Epub 2008 Nov 12.
    • (2010) Comp. Immunol. Microbiol. Infect. Dis. , vol.33 , Issue.3 , pp. 197-213
    • Chaung, H.C.1    Chen, C.W.2    Hsieh, B.L.3    Chung, W.B.4
  • 10
    • 43449086682 scopus 로고    scopus 로고
    • Attenuated cytokine responses in porcine lymph node cells stimulated with CpG DNA are associated with low frequency of IFNalpha-producing cells and TLR9 mRNA expression
    • Dar A., Nichani A.K., Benjamin P., Lai K., Soita H., Krieg A.M., Potter A., Babiuk L.A., Mutwiri G.K. Attenuated cytokine responses in porcine lymph node cells stimulated with CpG DNA are associated with low frequency of IFNalpha-producing cells and TLR9 mRNA expression. Vet. Immunol. Immunopathol. 2008, 123:324-336.
    • (2008) Vet. Immunol. Immunopathol. , vol.123 , pp. 324-336
    • Dar, A.1    Nichani, A.K.2    Benjamin, P.3    Lai, K.4    Soita, H.5    Krieg, A.M.6    Potter, A.7    Babiuk, L.A.8    Mutwiri, G.K.9
  • 12
    • 0025290760 scopus 로고
    • The effect of interferon induction in newborn piglets on the humoral immune response to oral vaccination with transmissible gastroenteritis virus
    • Derbyshire J.B., Lesnick C.E. The effect of interferon induction in newborn piglets on the humoral immune response to oral vaccination with transmissible gastroenteritis virus. Vet. Immunol. Immunopathol. 1990, 24:227-234.
    • (1990) Vet. Immunol. Immunopathol. , vol.24 , pp. 227-234
    • Derbyshire, J.B.1    Lesnick, C.E.2
  • 13
    • 13444269087 scopus 로고    scopus 로고
    • Human monocyte isolation methods influence cytokine production from in vitro generated dendritic cells
    • Elkord E., Williams P.E., Kynaston H., Rowbottom A.W. Human monocyte isolation methods influence cytokine production from in vitro generated dendritic cells. Immunology 2005, 114:204-212.
    • (2005) Immunology , vol.114 , pp. 204-212
    • Elkord, E.1    Williams, P.E.2    Kynaston, H.3    Rowbottom, A.W.4
  • 14
    • 34347250432 scopus 로고    scopus 로고
    • The role of type I interferon production by dendritic cells in host defense
    • Fitzgerald-Bocarsly P., Feng D. The role of type I interferon production by dendritic cells in host defense. Biochimie 2007, 89:843-855.
    • (2007) Biochimie , vol.89 , pp. 843-855
    • Fitzgerald-Bocarsly, P.1    Feng, D.2
  • 16
    • 2342497250 scopus 로고    scopus 로고
    • Type-A CpG oligonucleotides activate exclusively porcine natural interferon-producing cells to secrete interferon-alpha, tumour necrosis factor-alpha and interleukin-12
    • Guzylack-Piriou L., Balmelli C., McCullough K.C., Summerfield A. Type-A CpG oligonucleotides activate exclusively porcine natural interferon-producing cells to secrete interferon-alpha, tumour necrosis factor-alpha and interleukin-12. Immunology 2004, 112:28-37.
    • (2004) Immunology , vol.112 , pp. 28-37
    • Guzylack-Piriou, L.1    Balmelli, C.2    McCullough, K.C.3    Summerfield, A.4
  • 17
    • 33645817521 scopus 로고    scopus 로고
    • Role of natural interferon-producing cells and T lymphocytes in porcine monocyte-derived dendritic cell maturation
    • Guzylack-Piriou L., Piersma S., McCullough K., Summerfield A. Role of natural interferon-producing cells and T lymphocytes in porcine monocyte-derived dendritic cell maturation. Immunology 2006, 118:78-87.
    • (2006) Immunology , vol.118 , pp. 78-87
    • Guzylack-Piriou, L.1    Piersma, S.2    McCullough, K.3    Summerfield, A.4
  • 18
    • 0037726807 scopus 로고    scopus 로고
    • A phase I study of the safety and immunogenicity of recombinant hepatitis B surface antigen co-administered with an immunostimulatory phosphorothioate oligonucleotide adjuvant
    • Halperin S.A., Van Nest G., Smith B., Abtahi S., Whiley H., Eiden J.J. A phase I study of the safety and immunogenicity of recombinant hepatitis B surface antigen co-administered with an immunostimulatory phosphorothioate oligonucleotide adjuvant. Vaccine 2003, 21:2461-2467.
    • (2003) Vaccine , vol.21 , pp. 2461-2467
    • Halperin, S.A.1    Van Nest, G.2    Smith, B.3    Abtahi, S.4    Whiley, H.5    Eiden, J.J.6
  • 19
    • 33845224163 scopus 로고    scopus 로고
    • Vaccination with recombinant fusion proteins incorporating Toll-like receptor ligands induces rapid cellular and humoral immunity
    • Huleatt J.W., Jacobs A.R., Tang J., Desai P., Kopp E.B., Huang Y., Song L., Nakaar V., Powell T.J. Vaccination with recombinant fusion proteins incorporating Toll-like receptor ligands induces rapid cellular and humoral immunity. Vaccine 2007, 25:763-775.
    • (2007) Vaccine , vol.25 , pp. 763-775
    • Huleatt, J.W.1    Jacobs, A.R.2    Tang, J.3    Desai, P.4    Kopp, E.B.5    Huang, Y.6    Song, L.7    Nakaar, V.8    Powell, T.J.9
  • 21
    • 35349002727 scopus 로고    scopus 로고
    • E6020: a synthetic Toll-like receptor 4 agonist as a vaccine adjuvant
    • Ishizaka S.T., Hawkins L.D. E6020: a synthetic Toll-like receptor 4 agonist as a vaccine adjuvant. Expert Rev. Vaccines 2007, 6:773-784.
    • (2007) Expert Rev. Vaccines , vol.6 , pp. 773-784
    • Ishizaka, S.T.1    Hawkins, L.D.2
  • 22
    • 36448980927 scopus 로고    scopus 로고
    • Classical swine fever virus induces activation of plasmacytoid and conventional dendritic cells in tonsil, blood, and spleen of infected pigs
    • Jamin A., Gorin S., Cariolet R., Le Potier M.F., Kuntz-Simon G. Classical swine fever virus induces activation of plasmacytoid and conventional dendritic cells in tonsil, blood, and spleen of infected pigs. Vet. Res. 2008, 39:7.
    • (2008) Vet. Res. , vol.39 , pp. 7
    • Jamin, A.1    Gorin, S.2    Cariolet, R.3    Le Potier, M.F.4    Kuntz-Simon, G.5
  • 23
    • 33750309038 scopus 로고    scopus 로고
    • Characterization of conventional and plasmacytoid dendritic cells in swine secondary lymphoid organs and blood
    • Jamin A., Gorin S., Le Potier M.F., Kuntz-Simon G. Characterization of conventional and plasmacytoid dendritic cells in swine secondary lymphoid organs and blood. Vet. Immunol. Immunopathol. 2006, 114:224-237.
    • (2006) Vet. Immunol. Immunopathol. , vol.114 , pp. 224-237
    • Jamin, A.1    Gorin, S.2    Le Potier, M.F.3    Kuntz-Simon, G.4
  • 24
    • 0035179882 scopus 로고    scopus 로고
    • Specialization and complementarity in microbial molecule recognition by human myeloid and plasmacytoid dendritic cells
    • Jarrossay D., Napolitani G., Colonna M., Sallusto F., Lanzavecchia A. Specialization and complementarity in microbial molecule recognition by human myeloid and plasmacytoid dendritic cells. Eur. J. Immunol. 2001, 31:3388-3393.
    • (2001) Eur. J. Immunol. , vol.31 , pp. 3388-3393
    • Jarrossay, D.1    Napolitani, G.2    Colonna, M.3    Sallusto, F.4    Lanzavecchia, A.5
  • 25
    • 34248582612 scopus 로고    scopus 로고
    • TLR7 imidazoquinoline ligand 3M-019 is a potent adjuvant for pure protein prototype vaccines
    • Johnston D., Zaidi B., Bystryn J.C. TLR7 imidazoquinoline ligand 3M-019 is a potent adjuvant for pure protein prototype vaccines. Cancer Immunol. Immunother. 2007, 56:1133-1141.
    • (2007) Cancer Immunol. Immunother. , vol.56 , pp. 1133-1141
    • Johnston, D.1    Zaidi, B.2    Bystryn, J.C.3
  • 26
    • 0035903288 scopus 로고    scopus 로고
    • Subsets of human dendritic cell precursors express different toll-like receptors and respond to different microbial antigens
    • Kadowaki N., Ho S., Antonenko S., Malefyt R.W., Kastelein R.A., Bazan F., Liu Y.J. Subsets of human dendritic cell precursors express different toll-like receptors and respond to different microbial antigens. J. Exp. Med. 2001, 194:863-869.
    • (2001) J. Exp. Med. , vol.194 , pp. 863-869
    • Kadowaki, N.1    Ho, S.2    Antonenko, S.3    Malefyt, R.W.4    Kastelein, R.A.5    Bazan, F.6    Liu, Y.J.7
  • 28
    • 33748963475 scopus 로고    scopus 로고
    • In vivo effects of oligodeoxynucleotides containing synthetic immunostimulatory motifs in the immune response to swine streptococcic septicemia vaccine in weaned piglets
    • Linghua Z., Xingshan T., Fengzhen Z. In vivo effects of oligodeoxynucleotides containing synthetic immunostimulatory motifs in the immune response to swine streptococcic septicemia vaccine in weaned piglets. Mol. Immunol. 2007, 44:1141-1149.
    • (2007) Mol. Immunol. , vol.44 , pp. 1141-1149
    • Linghua, Z.1    Xingshan, T.2    Fengzhen, Z.3
  • 29
    • 33846650334 scopus 로고    scopus 로고
    • Vaccination with porcine reproductive and respiratory syndrome killed virus vaccine and immunostimulatory oligodeoxynucleotides induces specific immunity in piglets
    • Linghua Z., Xingshan T., Fengzhen Z. Vaccination with porcine reproductive and respiratory syndrome killed virus vaccine and immunostimulatory oligodeoxynucleotides induces specific immunity in piglets. Vaccine 2007, 25:1735-1742.
    • (2007) Vaccine , vol.25 , pp. 1735-1742
    • Linghua, Z.1    Xingshan, T.2    Fengzhen, Z.3
  • 30
    • 33644797214 scopus 로고    scopus 로고
    • Co-administration of porcine-specific CpG oligodeoxynucleotide enhances the immune responses to pseudorabies attenuated virus vaccine in newborn piglets in vivo
    • Linghua Z., Yong G., Xingshan T., Fengzhen Z. Co-administration of porcine-specific CpG oligodeoxynucleotide enhances the immune responses to pseudorabies attenuated virus vaccine in newborn piglets in vivo. Dev. Comp. Immunol. 2006, 30:589-596.
    • (2006) Dev. Comp. Immunol. , vol.30 , pp. 589-596
    • Linghua, Z.1    Yong, G.2    Xingshan, T.3    Fengzhen, Z.4
  • 31
    • 33847068799 scopus 로고    scopus 로고
    • Advances in swine biomedical model genomics
    • Lunney J.K. Advances in swine biomedical model genomics. Int. J. Biol. Sci. 2007, 3:179-184.
    • (2007) Int. J. Biol. Sci. , vol.3 , pp. 179-184
    • Lunney, J.K.1
  • 32
    • 7044247326 scopus 로고    scopus 로고
    • Cytokines and synthetic double-stranded RNA augment the T helper 1 immune response of swine to porcine reproductive and respiratory syndrome virus
    • Meier W.A., Husmann R.J., Schnitzlein W.M., Osorio F.A., Lunney J.K., Zuckermann F.A. Cytokines and synthetic double-stranded RNA augment the T helper 1 immune response of swine to porcine reproductive and respiratory syndrome virus. Vet. Immunol. Immunopathol. 2004, 102:299-314.
    • (2004) Vet. Immunol. Immunopathol. , vol.102 , pp. 299-314
    • Meier, W.A.1    Husmann, R.J.2    Schnitzlein, W.M.3    Osorio, F.A.4    Lunney, J.K.5    Zuckermann, F.A.6
  • 33
    • 0142058176 scopus 로고    scopus 로고
    • Recent advances in the discovery and delivery of vaccine adjuvants
    • O'Hagan D.T., Valiante N.M. Recent advances in the discovery and delivery of vaccine adjuvants. Nat. Rev. Drug Discov. 2003, 2:727-735.
    • (2003) Nat. Rev. Drug Discov. , vol.2 , pp. 727-735
    • O'Hagan, D.T.1    Valiante, N.M.2
  • 34
    • 27744607686 scopus 로고    scopus 로고
    • Distinct roles for the NF-kappaB1 and c-Rel transcription factors in the differentiation and survival of plasmacytoid and conventional dendritic cells activated by TLR-9 signals
    • O'Keeffe M., Grumont R.J., Hochrein H., Fuchsberger M., Gugasyan R., Vremec D., Shortman K., Gerondakis S. Distinct roles for the NF-kappaB1 and c-Rel transcription factors in the differentiation and survival of plasmacytoid and conventional dendritic cells activated by TLR-9 signals. Blood 2005, 106:3457-3464.
    • (2005) Blood , vol.106 , pp. 3457-3464
    • O'Keeffe, M.1    Grumont, R.J.2    Hochrein, H.3    Fuchsberger, M.4    Gugasyan, R.5    Vremec, D.6    Shortman, K.7    Gerondakis, S.8
  • 35
    • 0036525950 scopus 로고    scopus 로고
    • IFN-alpha2a induces IP-10/CXCL10 and MIG/CXCL9 production in monocyte-derived dendritic cells and enhances their capacity to attract and stimulate CD8+ effector T cells
    • Padovan E., Spagnoli G.C., Ferrantini M., Heberer M. IFN-alpha2a induces IP-10/CXCL10 and MIG/CXCL9 production in monocyte-derived dendritic cells and enhances their capacity to attract and stimulate CD8+ effector T cells. J. Leukoc. Biol. 2002, 71:669-676.
    • (2002) J. Leukoc. Biol. , vol.71 , pp. 669-676
    • Padovan, E.1    Spagnoli, G.C.2    Ferrantini, M.3    Heberer, M.4
  • 36
    • 57849113547 scopus 로고    scopus 로고
    • Characterization of interaction between porcine reproductive and respiratory syndrome virus and porcine dendritic cells
    • Park J.Y., Kim H.S., Seo S.H. Characterization of interaction between porcine reproductive and respiratory syndrome virus and porcine dendritic cells. J. Microbiol. Biotechnol. 2008, 18:1709-1716.
    • (2008) J. Microbiol. Biotechnol. , vol.18 , pp. 1709-1716
    • Park, J.Y.1    Kim, H.S.2    Seo, S.H.3
  • 37
    • 0037114141 scopus 로고    scopus 로고
    • Cutting edge: differential chemokine production by myeloid and plasmacytoid dendritic cells
    • Penna G., Vulcano M., Roncari A., Facchetti F., Sozzani S., Adorini L. Cutting edge: differential chemokine production by myeloid and plasmacytoid dendritic cells. J. Immunol. 2002, 169:6673-6676.
    • (2002) J. Immunol. , vol.169 , pp. 6673-6676
    • Penna, G.1    Vulcano, M.2    Roncari, A.3    Facchetti, F.4    Sozzani, S.5    Adorini, L.6
  • 39
    • 33645518610 scopus 로고    scopus 로고
    • Upon viral exposure, myeloid and plasmacytoid dendritic cells produce 3 waves of distinct chemokines to recruit immune effectors
    • Piqueras B., Connolly J., Freitas H., Palucka A.K., Banchereau J. Upon viral exposure, myeloid and plasmacytoid dendritic cells produce 3 waves of distinct chemokines to recruit immune effectors. Blood 2006, 107:2613-2618.
    • (2006) Blood , vol.107 , pp. 2613-2618
    • Piqueras, B.1    Connolly, J.2    Freitas, H.3    Palucka, A.K.4    Banchereau, J.5
  • 41
    • 22144432944 scopus 로고    scopus 로고
    • Toll-like receptor, MHC II, B7 and cytokine expression by porcine monocytes and monocyte-derived dendritic cells in response to microbial pathogen-associated molecular patterns
    • Raymond C.R., Wilkie B.N. Toll-like receptor, MHC II, B7 and cytokine expression by porcine monocytes and monocyte-derived dendritic cells in response to microbial pathogen-associated molecular patterns. Vet. Immunol. Immunopathol. 2005, 107:235-247.
    • (2005) Vet. Immunol. Immunopathol. , vol.107 , pp. 235-247
    • Raymond, C.R.1    Wilkie, B.N.2
  • 42
    • 33744521498 scopus 로고    scopus 로고
    • The adjuvant effects of the toll-like receptor 3 ligand polyinosinic-cytidylic acid poly (I:C) on antigen-specific CD8+ T cell responses are partially dependent on NK cells with the induction of a beneficial cytokine milieu
    • Salem M.L., El-Naggar S.A., Kadima A., Gillanders W.E., Cole D.J. The adjuvant effects of the toll-like receptor 3 ligand polyinosinic-cytidylic acid poly (I:C) on antigen-specific CD8+ T cell responses are partially dependent on NK cells with the induction of a beneficial cytokine milieu. Vaccine 2006, 24:5119-5132.
    • (2006) Vaccine , vol.24 , pp. 5119-5132
    • Salem, M.L.1    El-Naggar, S.A.2    Kadima, A.3    Gillanders, W.E.4    Cole, D.J.5
  • 45
    • 44949231424 scopus 로고    scopus 로고
    • Analyzing real-time PCR data by the comparative C(T) method
    • Schmittgen T.D., Livak K.J. Analyzing real-time PCR data by the comparative C(T) method. Nat. Protoc. 2008, 3:1101-1108.
    • (2008) Nat. Protoc. , vol.3 , pp. 1101-1108
    • Schmittgen, T.D.1    Livak, K.J.2
  • 46
    • 39449128293 scopus 로고    scopus 로고
    • Th17 T cells: linking innate and adaptive immunity
    • Stockinger B., Veldhoen M., Martin B. Th17 T cells: linking innate and adaptive immunity. Semin. Immunol. 2007, 19:353-361.
    • (2007) Semin. Immunol. , vol.19 , pp. 353-361
    • Stockinger, B.1    Veldhoen, M.2    Martin, B.3
  • 49
  • 50
    • 0035972043 scopus 로고    scopus 로고
    • The adjuvant effect of synthetic oligodeoxynucleotide containing CpG motif converts the anti-Haemophilus influenzae type b glycoconjugates into efficient anti-polysaccharide and anti-carrier polyvalent vaccines
    • von Hunolstein C., Mariotti S., Teloni R., Alfarone G., Romagnoli G., Orefici G., Nisini R. The adjuvant effect of synthetic oligodeoxynucleotide containing CpG motif converts the anti-Haemophilus influenzae type b glycoconjugates into efficient anti-polysaccharide and anti-carrier polyvalent vaccines. Vaccine 2001, 19:3058-3066.
    • (2001) Vaccine , vol.19 , pp. 3058-3066
    • von Hunolstein, C.1    Mariotti, S.2    Teloni, R.3    Alfarone, G.4    Romagnoli, G.5    Orefici, G.6    Nisini, R.7
  • 51
    • 33846414395 scopus 로고    scopus 로고
    • Porcine reproductive and respiratory syndrome virus productively infects monocyte-derived dendritic cells and compromises their antigen-presenting ability
    • Wang X., Eaton M., Mayer M., Li H., He D., Nelson E., Christopher-Hennings J. Porcine reproductive and respiratory syndrome virus productively infects monocyte-derived dendritic cells and compromises their antigen-presenting ability. Arch. Virol. 2007, 152:289-303.
    • (2007) Arch. Virol. , vol.152 , pp. 289-303
    • Wang, X.1    Eaton, M.2    Mayer, M.3    Li, H.4    He, D.5    Nelson, E.6    Christopher-Hennings, J.7


* 이 정보는 Elsevier사의 SCOPUS DB에서 KISTI가 분석하여 추출한 것입니다.