登革病毒(dengue virus; DV)是一種具脂套膜的單股RNA病毒，屬於黃病毒科中黃病毒屬的DV亞屬，經由節肢動物感染人類，主要以埃及斑蚊和白線斑蚊叮咬宿主的途徑進而傳播給感染者並引起疾病的發生；流行病學的統計顯示登革病毒好發於在熱帶與亞熱帶國家，由以東南亞為最，是目前台灣地區很重要的公共衛生問題。
登革病毒感染會造成兩種病症：較輕微的登革熱及會致命的登革出血熱/登革休克症狀。登革熱會造成發燒、血管浸潤、嗜中性球低下症及補體活化等臨床症狀。而嗜中性球是人體內最重要的第一線防禦細胞，在受到外來微生物的侵入後，嗜中性球會受吸引到發炎組織並清除病原。嗜中性球在清除外來微生物(細菌)，目前已研究的相當透澈，然而嗜中性球在病毒感染的角色至今還不是很清楚。因此在本篇的研究我們想了解嗜中性球在登革病毒感染的角色，我們利用純化出的嗜中性球和登革病毒在體外培養，進而去了解嗜中性球受登革病毒刺激後對於病毒及嗜中性球生物活性的影響。
實驗結果顯示活的登革病毒可以使嗜中性球的存活率下降並使IL-8 MIP-1a與MIP-1b等化學趨化激素和LDH的上升，而利用紫外光去活性的登革病毒只發現到MIP-1b的產生。此外利用MPO酵素來作為觀察嗜中性球去顆粒作用的指標，發現不論是登革病毒的存活與否皆可刺激MPO的產生，而在登革病人的血清中也可以偵測到大量的MPO與IL-8含量。
另一方面我們利用共軛焦顯微鏡發現登革病毒可以藉由嗜中性球的吞噬作用進入體內，並刺激使得嗜中性球細胞表面的CD11b與TLR4表現量增加，同時我們也觀測到登革病毒也可使內皮細胞表面表現ICAM-1黏著分子增加並使得嗜中性球較易和內皮細胞黏著。
綜而言之，嗜中性球可以經由吞噬作用殺死登革病毒並活化產生化學趨化激素、去顆粒酵素與細胞表面的黏著分子，這些變化可能導致嗜中性球壞死及較易和內皮細胞黏著而造成嗜中性球減少及相關病變。

Dengue viruses (DV) are lipid-enveloped RNA viruses, which are transmitted by the mosquito vectors, Aedes aegypti and Aedes albopictus. DV are the most important flaviviruses in tropical and subtropical countries. Infection with DV may cause mild dengue fever or life threatening diseases such as dengue hemorrhagic fever and dengue shock syndrome. Vascular leakage, hemorrhage, neutropenia and complement activation are the hallmarks of these diseases. Polymorphonuclear leukocytes (PMNs) or neutrophils are critical effectors cells of the innate immune system, which can protect hosts by migrating to inflammatory sites and killing pathogen. However, the role of PMNs in the pathogenesis of DV infection is unclear. In this study, human neutrophils were incubated with DV to understand the effect of DV on the biological activities of neutrophils. Live but not UV inactivated DV (UV-DV) decreased the viability of neutrophils and increased the release of LDH and chemokines such as IL-8, and macrophage inflammatory protein (MIP-1a) from neutrophils. However, the granule enzyme, myeloperoxidase (MPO), was released from both live and UV-DV-stimulated neutrophils. In addition, the levels of IL-8 and MPO in the sera of dengue patients were also increased. Using fluorescent confocal microscopy, we found that DV was phagocytosed into neutrophils and co-localized with FITC-beads in neutrophils. Furthermore, DV-stimulation also increased the expression of CD11b neutrophils and ICAM-1 of HMEC-1 endothelial cell line and increased the binding of neutrophils to endothelial cell. In addition, the signal transduction molecule Toll-like receptor 4 (TLR4) was also increased in DV stimulated neutrophils. Taken together, neutrophils can uptake DV through phagocytosis and kill the virus. In this process, adherence of neutrophils to endothelial cells and necrosis of neutrophils were increased along with the release of chemokines, granule enzymes, and the expression of surface molecule. Therefore neutrophils may play important roles in the innate immune response against DV infection and may also contribute to the pathogenesis of dengue virus infection.

Aaskov, J. G., H. M. Geysen, et al. (1989). "Serologically defined linear epitopes in the envelope protein of dengue 2 (Jamaica strain 1409)." Arch Virol 105(3-4): 209-21.
Alam, R., P. A. Forsythe, et al. (1992). "Macrophage inflammatory protein-1 alpha activates basophils and mast cells." J Exp Med 176(3): 781-6.
Baggiolini, M., A. Walz, et al. (1989). "Neutrophil-activating peptide-1/interleukin 8, a novel cytokine that activates neutrophils." J Clin Invest 84(4): 1045-9.
Baldelli, F., R. Preziosi, et al. (2000). "Programmed granulocyte neutrophil death in patients at different stages of HIV infection." Aids 14(8): 1067-9.
Bale, J. F., Jr., M. E. O'Neil, et al. (1985). "The interaction of murine cytomegalovirus with murine neutrophils: effect on migratory and phagocytic activities." J Leukoc Biol 38(6): 723-34.
Bandres, J. C., J. Trial, et al. (1993). "Increased phagocytosis and generation of reactive oxygen products by neutrophils and monocytes of men with stage 1 human immunodeficiency virus infection." J Infect Dis 168(1): 75-83.
Bhamarapravati, N. and S. Yoksan (1989). "Study of bivalent dengue vaccine in volunteers." Lancet 1(8646): 1077.
Bielefeldt-Ohmann, H., M. Meyer, et al. (2001). "Dengue virus binding to human leukocyte cell lines: receptor usage differs between cell types and virus strains." Virus Res 73(1): 81-9.
Burg, N. D. and M. H. Pillinger (2001). "The neutrophil: function and regulation in innate and humoral immunity." Clin Immunol 99(1): 7-17.
Butthep, P., A. Bunyaratvej, et al. (1993). "Dengue virus and endothelial cell: a related phenomenon to thrombocytopenia and granulocytopenia in dengue hemorrhagic fever." Southeast Asian J Trop Med Public Health 24 Suppl 1: 246-9.
Casali, P. and M. B. Oldstone (1983). "Immune complexes in viral infection." Curr Top Microbiol Immunol 104: 7-48.
Cassatella, M. A. (1995). "The production of cytokines by polymorphonuclear neutrophils." Immunol Today 16(1): 21-6.
Chang, D. M. and M. F. Shaio (1994). "Production of interleukin-1 (IL-1) and IL-1 inhibitor by human monocytes exposed to dengue virus." J Infect Dis 170(4): 811-7.
Chen, Y., T. Maguire, et al. (1997). "Dengue virus infectivity depends on envelope protein binding to target cell heparan sulfate." Nat Med 3(8): 866-71.
Chen, Y. C., S. Y. Wang, et al. (1999). "Bacterial lipopolysaccharide inhibits dengue virus infection of primary human monocytes/macrophages by blockade of virus entry via a CD14-dependent mechanism." J Virol 73(4): 2650-7.
Cinatl, J., Jr., R. Blaheta, et al. (2000). "Decreased neutrophil adhesion to human cytomegalovirus-infected retinal pigment epithelial cells is mediated by virus-induced up-regulation of Fas ligand independent of neutrophil apoptosis." J Immunol 165(8): 4405-13.
Debets-Ossenkopp, Y., E. L. Mills, et al. (1982). "Effect of influenza virus on phagocytic cells." Eur J Clin Microbiol 1(3): 171-7.
Domachowske, J. B., C. A. Bonville, et al. (2000). "The chemokine macrophage-inflammatory protein-1 alpha and its receptor CCR1 control pulmonary inflammation and antiviral host defense in paramyxovirus infection." J Immunol 165(5): 2677-82.
Dooley, J. R. and J. S. Burkle (1966). "Three faces of dengue." Arch Intern Med 117(2): 170-4.
Duesberg, U., A. von dem Bussche, et al. (2002). "Cell activation by synthetic lipopeptides of the hepatitis C virus (HCV)--core protein is mediated by toll like receptors (TLRs) 2 and 4." Immunol Lett 84(2): 89-95.
Elbim, C., S. Pillet, et al. (2001). "The role of phagocytes in HIV-related oxidative stress." J Clin Virol 20(3): 99-109.
Engelich, G., M. White, et al. (2002). "Role of the respiratory burst in co-operative reduction in neutrophil survival by influenza A virus and Escherichia coli." J Med Microbiol 51(6): 484-90.
Friedland, J. S. (1996). "Chemokines in viral disease." Res Virol 147(2-3): 131-8.
Gagnon, S. J., F. A. Ennis, et al. (1999). "Bystander target cell lysis and cytokine production by dengue virus-specific human CD4(+) cytotoxic T-lymphocyte clones." J Virol 73(5): 3623-9.
Graham, G. J., E. G. Wright, et al. (1990). "Identification and characterization of an inhibitor of haemopoietic stem cell proliferation." Nature 344(6265): 442-4.
Green, S., D. W. Vaughn, et al. (1999). "Early immune activation in acute dengue illness is related to development of plasma leakage and disease severity." J Infect Dis 179(4): 755-62.
Gregson, A. and R. Edelman (2003). "Dengue virus infection." Pediatr Infect Dis J 22(2): 179-81.
Gubler, D. J. (1998). "Dengue and dengue hemorrhagic fever." Clin Microbiol Rev 11(3): 480-96.
Gubler, D. J., D. Reed, et al. (1978). "Epidemiologic, clinical, and virologic observations on dengue in the Kingdom of Tonga." Am J Trop Med Hyg 27(3): 581-9.
Guzman, M. G. and G. Kouri (2002). "Dengue: an update." Lancet Infect Dis 2(1): 33-42.
Halstead, S. B. (1982). "Immune enhancement of viral infection." Prog Allergy 31: 301-64.
Halstead, S. B. and E. J. O'Rourke (1977). "Antibody-enhanced dengue virus infection in primate leukocytes." Nature 265(5596): 739-41.
Halstead, S. B., J. S. Porterfield, et al. (1980). "Enhancement of dengue virus infection in monocytes by flavivirus antisera." Am J Trop Med Hyg 29(4): 638-42.
Harn, M. R., Y. L. Chiang, et al. (1993). "[The 1991 dengue epidemic in Kaohsiung City]." J Formos Med Assoc 92 Suppl 1: S39-43.
Heldenberg, D. (1999). "[Severe transient neutropenia due to parvovirus B19]." Harefuah 137(3-4): 113-4, 174.
Henchal, E. A. and J. R. Putnak (1990). "The dengue viruses." Clin Microbiol Rev 3(4): 376-96.
Hober, D., A. S. Delannoy, et al. (1996). "High levels of sTNFR p75 and TNF alpha in dengue-infected patients." Microbiol Immunol 40(8): 569-73.
Hober, D., L. Poli, et al. (1993). "Serum levels of tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), and interleukin-1 beta (IL-1 beta) in dengue-infected patients." Am J Trop Med Hyg 48(3): 324-31.
Jaovisidha, P., M. E. Peeples, et al. (1999). "Respiratory syncytial virus stimulates neutrophil degranulation and chemokine release." J Immunol 163(5): 2816-20.
Jones, A., J. M. Qui, et al. (2002). "Neutrophil survival is prolonged in the airways of healthy infants and infants with RSV bronchiolitis." Eur Respir J 20(3): 651-7.
Juffrie, M., G. M. van Der Meer, et al. (2000). "Inflammatory mediators in dengue virus infection in children: interleukin-8 and its relationship to neutrophil degranulation." Infect Immun 68(2): 702-7.
Kaufmann, A., R. Salentin, et al. (2001). "Defense against influenza A virus infection: essential role of the chemokine system." Immunobiology 204(5): 603-13.
Keshavarzian, A., R. D. Fusunyan, et al. (1999). "Increased interleukin-8 (IL-8) in rectal dialysate from patients with ulcerative colitis: evidence for a biological role for IL-8 in inflammation of the colon." Am J Gastroenterol 94(3): 704-12.
King, A. D., A. Nisalak, et al. (1999). "B cells are the principal circulating mononuclear cells infected by dengue virus." Southeast Asian J Trop Med Public Health 30(4): 718-28.
King, C. A., J. S. Marshall, et al. (2000). "Release of vasoactive cytokines by antibody-enhanced dengue virus infection of a human mast cell/basophil line." J Virol 74(15): 7146-50.
Kuo, C. H., D. I. Tai, et al. (1992). "Liver biochemical tests and dengue fever." Am J Trop Med Hyg 47(3): 265-70.
Kurane, I., B. L. Innis, et al. (1991). "Activation of T lymphocytes in dengue virus infections. High levels of soluble interleukin 2 receptor, soluble CD4, soluble CD8, interleukin 2, and interferon-gamma in sera of children with dengue." J Clin Invest 88(5): 1473-80.
Kurane, I., B. L. Innis, et al. (1989). "Human T cell responses to dengue virus antigens. Proliferative responses and interferon gamma production." J Clin Invest 83(2): 506-13.
Kurt-Jones, E. A., L. Popova, et al. (2000). "Pattern recognition receptors TLR4 and CD14 mediate response to respiratory syncytial virus." Nat Immunol 1(5): 398-401.
La Russa, V. F. and B. L. Innis (1995). "Mechanisms of dengue virus-induced bone marrow suppression." Baillieres Clin Haematol 8(1): 249-70.
Larochelle, B., L. Flamand, et al. (1998). "Epstein-Barr virus infects and induces apoptosis in human neutrophils." Blood 92(1): 291-9.
Leff, J. A., M. A. Oppegard, et al. (1992). "Progressive increases in serum catalase activity in advancing human immunodeficiency virus infection." Free Radic Biol Med 13(2): 143-9.
Lin, S. F., H. W. Liu, et al. (1989). "[Hematological aspects of dengue fever]." Gaoxiong Yi Xue Ke Xue Za Zhi 5(1): 12-6.
Lin, Y. L., H. Y. Lei, et al. (2002). "Heparin inhibits dengue-2 virus infection of five human liver cell lines." Antiviral Res 56(1): 93-6.
Lin, Y. W., K. J. Wang, et al. (2002). "Virus replication and cytokine production in dengue virus-infected human B lymphocytes." J Virol 76(23): 12242-9.
Liu, H. W., T. L. Ho, et al. (1989). "Clinical observations of virologically confirmed dengue fever in the 1987 outbreak in southern Taiwan." Gaoxiong Yi Xue Ke Xue Za Zhi 5(1): 42-9.
Liu, W. T., C. L. Chen, et al. (1991). "Isolation of dengue virus with a human promonocyte cell line." Am J Trop Med Hyg 44(5): 494-9.
Lloyd, A. R. and J. J. Oppenheim (1992). "Poly's lament: the neglected role of the polymorphonuclear neutrophil in the afferent limb of the immune response." Immunol Today 13(5): 169-72.
Malasit, P. (1987). "Complement and dengue haemorrhagic fever/shock syndrome." Southeast Asian J Trop Med Public Health 18(3): 316-20.
Mentor, N. A. and I. Kurane (1997). "Dengue virus infection of human T lymphocytes." Acta Virol 41(3): 175-6.
Morens, D. M., S. B. Halstead, et al. (1987). "Profiles of antibody-dependent enhancement of dengue virus type 2 infection." Microb Pathog 3(4): 231-7.
Mori, M., I. Kurane, et al. (1997). "Cytokine production by dengue virus antigen-responsive human T lymphocytes in vitro examined using a double immunocytochemical technique." J Leukoc Biol 61(3): 338-45.
Murayama, T., N. Mukaida, et al. (2000). "The immediate early gene 1 product of human cytomegalovirus is sufficient for up-regulation of interleukin-8 gene expression." Biochem Biophys Res Commun 279(1): 298-304.
Nathanson, N., M. Davis, et al. (1966). "Histological studies of the monkey neurovirulence of group B arboviruses. II. Selection of indicator centers." Am J Epidemiol 84(3): 524-40.
Rizvi, N., U. C. Chaturvedi, et al. (1987). "Macrophage functions during dengue virus infection: antigenic stimulation of B cells." Immunology 62(3): 493-8.
Roebuck, K. A. (1999). "Oxidant stress regulation of IL-8 and ICAM-1 gene expression: differential activation and binding of the transcription factors AP-1 and NF-kappaB (Review)." Int J Mol Med 4(3): 223-30.
Rosen, L. (1977). "The Emperor's New Clothes revisited, or reflections on the pathogenesis of dengue hemorrhagic fever." Am J Trop Med Hyg 26(3): 337-43.
Rot, A., M. Krieger, et al. (1992). "RANTES and macrophage inflammatory protein 1 alpha induce the migration and activation of normal human eosinophil granulocytes." J Exp Med 176(6): 1489-95.
Rothman, A. L. and F. A. Ennis (1999). "Immunopathogenesis of Dengue hemorrhagic fever." Virology 257(1): 1-6.
Rudnick, A. (1967). "Aedes aegypti and haemorrhagic fever." Bull World Health Organ 36(4): 528-32.
Schall, T. J., K. Bacon, et al. (1993). "Human macrophage inflammatory protein alpha (MIP-1 alpha) and MIP-1 beta chemokines attract distinct populations of lymphocytes." J Exp Med 177(6): 1821-6.
Spain-Santana, T. A., S. Marglin, et al. (2001). "MIP-1 alpha and MIP-1 beta induction by dengue virus." J Med Virol 65(2): 324-30.
Stapleton, P. P., H. P. Redmond, et al. (1998). "Myeloperoxidase (MPO) may mediate neutrophil adherence to the endothelium through upregulation of CD11B expression--an effect downregulated by taurine." Adv Exp Med Biol 442: 183-92.
Takeda, K. and S. Akira (2001). "Regulation of innate immune responses by Toll-like receptors." Jpn J Infect Dis 54(6): 209-19.
Tassaneetrithep, B., T. H. Burgess, et al. (2003). "DC-SIGN (CD209) mediates dengue virus infection of human dendritic cells." J Exp Med 197(7): 823-9.
Taub, D. D., J. R. Ortaldo, et al. (1996). "Beta chemokines costimulate lymphocyte cytolysis, proliferation, and lymphokine production." J Leukoc Biol 59(1): 81-9.
Thein, S., M. M. Aung, et al. (1997). "Risk factors in dengue shock syndrome." Am J Trop Med Hyg 56(5): 566-72.
Vaughn, D. W., S. Green, et al. (1997). "Dengue in the early febrile phase: viremia and antibody responses." J Infect Dis 176(2): 322-30.
Wang, S. Z. and K. D. Forsyth (2000). "The interaction of neutrophils with respiratory epithelial cells in viral infection." Respirology 5(1): 1-10.
Wang, S. Z., P. K. Smith, et al. (1998). "The apoptosis of neutrophils is accelerated in respiratory syncytial virus (RSV)-induced bronchiolitis." Clin Exp Immunol 114(1): 49-54.
Willems, J., M. Joniau, et al. (1989). "Human granulocyte chemotactic peptide (IL-8) as a specific neutrophil degranulator: comparison with other monokines." Immunology 67(4): 540-2.
Wu, S. J., G. Grouard-Vogel, et al. (2000). "Human skin Langerhans cells are targets of dengue virus infection." Nat Med 6(7): 816-20.
Wu, Y. C. (1986). "[Epidemic dengue 2 on Liouchyou Shiang, Pingtung County in 1981]." Zhonghua Min Guo Wei Sheng Wu Ji Mian Yi Xue Za Zhi 19(3): 203-11.
Yang, J. J., R. Kettritz, et al. (1996). "Apoptosis of endothelial cells induced by the neutrophil serine proteases proteinase 3 and elastase." Am J Pathol 149(5): 1617-26.
Yang, K. D., C. L. Wang, et al. (1995). "Production of cytokines and platelet activating factor in secondary dengue virus infections." J Infect Dis 172(2): 604-5.
Zhu, Z., W. Tang, et al. (1997). "Rhinovirus stimulation of interleukin-8 in vivo and in vitro: role of NF-kappaB." Am J Physiol 273(4 Pt 1): L814-24.