嬰兒或小孩被腸病毒71型感染後，部分會導致嚴重的症狀甚至死亡。不幸的是，對於重症的病人，目前可行的照護方式也只能給予支持性的治療，因為目前沒有有效的抗腸病毒71型的藥物來治療病患。本實驗使用的三種抗病毒藥物，ribavirin，mycophenolic acid (MPA)，和6-azauridine，在先前的研究都顯示能在試管內有效的抑制不同種類病毒的感染，ribavirin也被應用在臨床上治療病毒感染。我們首先利用人類肌肉細胞和神經元細胞來測試這些藥物對抗腸病毒的能力。在實驗中我們發現，三種藥物的處理都能減低腸病毒在細胞內的複製，並且減少細胞病變的產生以及保護細胞不被腸病毒感染。而這三種藥物對細胞的生長只有些微的影響，並且對細胞也只有少許的毒性，這說明了我們觀察到這些藥物可以抗腸病毒的現象，並不是因為這些藥物抑制了細胞的生長或是毒殺了細胞而造成的。進一步地，我們利用從腹腔感染腸病毒的小鼠模式，來測試這些藥物治療被腸病毒感染的小鼠的效果。由實驗結果發現，用ribavirin治療的小鼠，其中樞神經系統內病毒的含量，疾病的嚴重度及死亡率有顯著的降低，並且有70%的存活率，然而給予生理食鹽水當作控制組的小鼠，不只產生了嚴重的麻痺現象，其存活率也只有27%。因此我們認為，給予ribavirin的治療能保護被腸病毒感染的小鼠。然而，MPA或6-azauridine的治療卻無法降低疾病的嚴重度及死亡率。我們的實驗結果顯示ribavirin有作為抗腸病毒71型藥物的潛力。

Enterovirus 71 (EV71) infection causes severe syndromes and deaths in infants and young children. Unfortunately, only supportive care is available for infected patients so far, because there is no effective antiviral agent to control EV71 infection. There are three antiviral drugs, ribavirin, mycophenolic acid (MPA), and 6-azauridine, which have been shown to effectively inhibit several viral infections. In this study, we tested the anti-EV71 effects of these drugs in vitro using human muscle and neuronal cells. All three drugs were shown to reduce EV71 replication and cytopathic effect, and protect infected cells from EV71 infection. These drugs only slightly affected the proliferation of human muscle and neuronal cells and had little toxicity to the cells, indicating that the antiviral activities of these drugs were not likely due to their inhibition on cell proliferation or cytotoxicity. Furthermore, ICR mice infected with EV71 by intraperitoneal inoculation were used to test the efficacy of these drugs in vivo. Infected mice treated with ribavirin showed marked reduction in viral loads in the central nervous system, morbidity, and mortality with a 70% survival rate. In contrast, infected mice given only phosphate-buffered saline showed severe paralysis with a 27% survival rate. Thus, ribavirin treatment protected mice from EV71 infection. However, MPA and 6-azauridine did not protect EV71-infected mice from death and paralysis. Our data suggest that ribavirin could be a potential anti-EV71 agent.

1. Bougie, I., and M. Bisaillon. 2004. The broad spectrum antiviral nucleoside ribavirin as a substrate for a viral RNA capping enzyme. J Biol Chem 279:22124-30.
2. Briolant, S., D. Garin, N. Scaramozzino, A. Jouan, and J. M. Crance. 2004. In vitro inhibition of Chikungunya and Semliki Forest viruses replication by antiviral compounds: synergistic effect of interferon-alpha and ribavirin combination. Antiviral Res 61:111-7.
3. Bussereau, F., M. Picard, J. Blancou, and P. Sureau. 1988. Treatment of rabies in mice and foxes with antiviral compounds. Acta Virol 32:33-49.
4. Carr, S. F., E. Papp, J. C. Wu, and Y. Natsumeda. 1993. Characterization of human type I and type II IMP dehydrogenases. J Biol Chem 268:27286-90.
5. Chumakov, K. M., I. K. Lavrova, L. I. Martianova, M. B. Korolev, V. N. Bashkirtsev, and M. K. Voroshilova. 1979. Investigation of physicochemical properties of Bulgarian strain 258 of enterovirus type 71. Brief report. Arch Virol 60:359-62.
6. Crance, J. M., N. Scaramozzino, A. Jouan, and D. Garin. 2003. Interferon, ribavirin, 6-azauridine and glycyrrhizin: antiviral compounds active against pathogenic flaviviruses. Antiviral Res 58:73-9.
7. Crotty, S., and R. Andino. 2002. Implications of high RNA virus mutation rates: lethal mutagenesis and the antiviral drug ribavirin. Microbes Infect 4:1301-7.
8. Crotty, S., C. E. Cameron, and R. Andino. 2001. RNA virus error catastrophe: direct molecular test by using ribavirin. Proc Natl Acad Sci U S A 98:6895-900.
9. Crotty, S., D. Maag, J. J. Arnold, W. Zhong, J. Y. Lau, Z. Hong, R. Andino, and C. E. Cameron. 2000. The broad-spectrum antiviral ribonucleoside ribavirin is an RNA virus mutagen. Nat Med 6:1375-9.
10. Danes, L., E. Sladka, J. Hancil, and J. Horacek. 1988. Cross reactivity among human enterovirus serotypes as revealed by microneutralization assay technique. J Hyg Epidemiol
Microbiol Immunol 32:233-8.
11. Davis, G. L., R. Esteban-Mur, V. Rustgi, J. Hoefs, S. C. Gordon, C. Trepo, M. L. Shiffman, S. Zeuzem, A. Craxi, M. H. Ling, and J. Albrecht. 1998. Interferon alfa-2b alone or in combination with ribavirin for the treatment of relapse of chronic hepatitis C. International Hepatitis Interventional Therapy Group. N Engl J Med 339:1493-9.
12. Dostal, M., and R. Jelinek. 1979. Embryotoxicity of transplacentally and intraamniotically administered 6-azauridine in mice. Teratology 19:143-8.
13. Fuchizaki, U., S. Kaneko, Y. Nakamoto, Y. Sugiyama, K. Imagawa, M. Kikuchi, and K. Kobayashi. 2003. Synergistic antiviral effect of a combination of mouse interferon-alpha and interferon-gamma on mouse hepatitis virus. J Med Virol 69:188-94.
14. Gilbert, G. L., K. E. Dickson, M. J. Waters, M. L. Kennett, S. A. Land, and M. Sneddon. 1988. Outbreak of enterovirus 71 infection in Victoria, Australia, with a high incidence of neurologic involvement. Pediatr Infect Dis J 7:484-8.
15. Gong, Z. J., S. De Meyer, C. Clarysse, C. Verslype, J. Neyts, E. De Clercq, and S. H. Yap. 1999. Mycophenolic acid, an immunosuppressive agent, inhibits HBV replication in vitro. J Viral Hepat 6:229-36.
16. Hagiwara, A., I. Tagaya, and T. Yoneyama. 1978. Epidemic of hand, foot and mouth disease associated with enterovirus 71 infection. Intervirology 9:60-3.
17. Hall, C. B., E. E. Walsh, J. F. Hruska, R. F. Betts, and W. J. Hall. 1983. Ribavirin treatment of experimental respiratory syncytial viral infection. A controlled double-blind study in young adults. Jama 249:2666-70.
18. Holland, J. J., E. Domingo, J. C. de la Torre, and D. A. Steinhauer. 1990. Mutation frequencies at defined single codon sites in vesicular stomatitis virus and poliovirus can be increased only slightly by chemical mutagenesis. J Virol 64:3960-2.
19. Hossain, M. M., J. J. Coull, G. L. Drusano, and D. M. Margolis. 2002. Dose proportional inhibition of HIV-1 replication by mycophenolic acid and synergistic inhibition in combination with abacavir, didanosine, and tenofovir. Antiviral Res 55:41-52.
20. Hsiung, G. D. a. J. R. W. 2000. Enterovirus infections with special reference to enterovirus 71. J. Microbiol. Immunol. Infect. 33:1-8.
21. Huang, Y. F., P. C. Chiu, C. C. Chen, Y. Y. Chen, K. S. Hsieh, Y. C. Liu, P. H. Lai, and H. W. Chang. 2003. Cardiac troponin I: a reliable marker and early myocardial involvement with meningoencephalitis after fatal enterovirus-71 infection. J Infect 46:238-43.
22. Huggins, J. W., C. M. Hsiang, T. M. Cosgriff, M. Y. Guang, J. I. Smith, Z. O. Wu, J. W. LeDuc, Z. M. Zheng, J. M. Meegan, Q. N. Wang, and et al. 1991. Prospective, double-blind, concurrent, placebo-controlled clinical trial of intravenous ribavirin therapy of hemorrhagic fever with renal syndrome. J Infect Dis 164:1119-27.
23. Ishimaru, Y., S. Nakano, K. Yamaoka, and S. Takami. 1980. Outbreaks of hand, foot, and mouth disease by enterovirus 71. High incidence of complication disorders of central nervous system. Arch Dis Child 55:583-8.
24. Jordan, I., T. Briese, N. Fischer, J. Y. Lau, and W. I. Lipkin. 2000. Ribavirin inhibits West Nile virus replication and cytopathic effect in neural cells. J Infect Dis 182:1214-7.
25. Kaiser, L., C. E. Crump, and F. G. Hayden. 2000. In vitro activity of pleconaril and AG7088 against selected serotypes and clinical isolates of human rhinoviruses. Antiviral Res 47:215-20.
26. Klein, R. J., A. E. Friedman-Kien, and E. Brady. 1974. Herpes simplex virus skin infection in hairless mice: treatment with antiviral compounds. Antimicrob Agents Chemother 5:318-22.
27. Lanford, R. E., D. Chavez, B. Guerra, J. Y. Lau, Z. Hong, K. M. Brasky, and B. Beames. 2001. Ribavirin induces error-prone replication of GB virus B in primary tamarin hepatocytes. J Virol 75:8074-81.
28. Lin, K. H., K. P. Hwang, G. M. Ke, C. F. Wang, L. Y. Ke, Y. T. Hsu, Y. C. Tung, P. Y. Chu, B. H. Chen, H. L. Chen, C. L. Kao, J. R. Wang, H. L. Eng, S. Y. Wang, L. C. Hsu, and H. Y. Chen. 2006. Evolution of EV71 genogroup in Taiwan from 1998 to 2005: an emerging of subgenogroup C4 of EV71. J Med Virol 78:254-62.
29. Lin, T. Y., L. Y. Chang, S. H. Hsia, Y. C. Huang, C. H. Chiu, C. Hsueh, S. R. Shih, C. C. Liu, and M. H. Wu. 2002. The 1998 enterovirus 71 outbreak in Taiwan: pathogenesis and management. Clin Infect Dis 34 Suppl 2:S52-7.
30. Lin, T. Y., S. J. Twu, M. S. Ho, L. Y. Chang, and C. Y. Lee. 2003. Enterovirus 71 outbreaks, Taiwan: occurrence and recognition. Emerg Infect Dis 9:291-3.
31. Malinoski, F. J., S. E. Hasty, M. A. Ussery, and J. M. Dalrymple. 1990. Prophylactic ribavirin treatment of dengue type 1 infection in rhesus monkeys. Antiviral Res 13:139-49.
32. McCormick, J. B., I. J. King, P. A. Webb, C. L. Scribner, R. B. Craven, K. M. Johnson, L. H. Elliott, and R. Belmont-Williams. 1986. Lassa fever. Effective therapy with ribavirin. N Engl J Med 314:20-6.
33. McJunkin, J. E., R. Khan, E. C. de los Reyes, D. L. Parsons, L. L. Minnich, R. G. Ashley, and T. F. Tsai. 1997. Treatment of severe La Crosse encephalitis with intravenous ribavirin following diagnosis by brain biopsy. Pediatrics 99:261-7.
34. McMinn, P. C. 2002. An overview of the evolution of enterovirus 71 and its clinical and public health significance. FEMS Microbiol Rev 26:91-107.
35. Mele, T. S., and P. F. Halloran. 2000. The use of mycophenolate mofetil in transplant recipients. Immunopharmacology 47:215-45.
36. Miles, K. K., S. T. Stern, P. C. Smith, F. K. Kessler, S. Ali, and J. K. Ritter. 2005. An investigation of human and rat liver microsomal mycophenolic acid glucuronidation: evidence for a principal role of UGT1A enzymes and species differences in UGT1A specificity. Drug Metab Dispos 33:1513-20.
37. Morrey, J. D., D. F. Smee, R. W. Sidwell, and C. Tseng. 2002. Identification of active antiviral compounds against a New York isolate of West Nile virus. Antiviral Res 55:107-16.
38. Nolan, M. A., M. E. Craig, M. M. Lahra, W. D. Rawlinson, P. C. Prager, G. D. Williams, A. M. Bye, and P. I. Andrews. 2003. Survival after pulmonary edema due to enterovirus 71 encephalitis. Neurology 60:1651-6.
39. Okamoto, M., Y. Wakabayashi, A. Higuchi, Y. Kadotani, S. Ogino, H. Ushigome, K. Akioka, S. Kaihara, and N. Yoshimura. 2005. Therapeutic drug monitoring of mycophenolic acid in renal transplant recipients. Transplant Proc 37:859-60.
40. Padalko, E., E. Verbeken, P. Matthys, J. L. Aerts, E. De Clercq, and J. Neyts. 2003. Mycophenolate mofetil inhibits the development of Coxsackie B3-virus-induced myocarditis in mice. BMC Microbiol 3:25.
41. Pevear, D. C., T. M. Tull, M. E. Seipel, and J. M. Groarke. 1999. Activity of pleconaril against enteroviruses. Antimicrob Agents Chemother 43:2109-15.
42. Schmidt, N. J., E. H. Lennette, and H. H. Ho. 1974. An apparently new enterovirus isolated from patients with disease of the central nervous system. Journal of Infectious Diseases 129:304-9.
43. Schmidt, N. J., E. H. Lennette, and H. H. Ho. 1974. An apparently new enterovirus isolated from patients with disease of the central nervous system. J Infect Dis 129:304-9.
44. Shia, K. S., W. T. Li, C. M. Chang, M. C. Hsu, J. H. Chern, M. K. Leong, S. N. Tseng, C. C. Lee, Y. C. Lee, S. J. Chen, K. C. Peng, H. Y. Tseng, Y. L. Chang, C. L. Tai, and S. R. Shih. 2002. Design, synthesis, and structure-activity relationship of pyridyl imidazolidinones: a novel class of potent and selective human enterovirus 71 inhibitors. J Med Chem 45:1644-55.
45. Shih, S. R., M. S. Ho, K. H. Lin, S. L. Wu, Y. T. Chen, C. N. Wu, T. Y. Lin, L. Y. Chang, K. C. Tsao, H. C. Ning, P. Y. Chang, S. M. Jung, C. Hsueh, and K. S. Chang. 2000. Genetic analysis of enterovirus 71 isolated from fatal and non-fatal cases of hand, foot and mouth disease during an epidemic in Taiwan, 1998. Virus Res 68:127-36.
46. Tam, R. C., B. Pai, J. Bard, C. Lim, D. R. Averett, U. T. Phan, and T. Milovanovic. 1999. Ribavirin polarizes human T cell responses towards a Type 1 cytokine profile. J Hepatol 30:376-82.
47. Thevenot, T., P. Mathurin, J. Moussalli, M. Perrin, F. Plassart, C. Blot, P. Opolon, and T. Poynard. 1997. Effects of cirrhosis, interferon and azathioprine on adverse events in patients with chronic hepatitis C treated with ribavirin. J Viral Hepat 4:243-53.
48. Wang, Y. F., C. T. Chou, H. Y. Lei, C. C. Liu, S. M. Wang, J. J. Yan, I. J. Su, J. R. Wang, T. M. Yeh, S. H. Chen, and C. K. Yu. 2004. A mouse-adapted enterovirus 71 strain causes neurological disease in mice after oral infection. J Virol 78:7916-24.
49. Wen, Y. Y., T. Y. Chang, S. T. Chen, C. Li, and H. S. Liu. 2003. Comparative study of enterovirus 71 infection of human cell lines. J Med Virol 70:109-18.
50. Wong, P. N., S. K. Mak, K. Y. Lo, G. M. Tong, Y. Wong, C. L. Watt, and A. K. Wong. 2003. Clinical presentation and outcome of severe acute respiratory syndrome in dialysis patients. Am J Kidney Dis 42:1075-81.
51. Wu, J., H. Y. Xie, G. P. Jiang, X. Xu, and S. S. Zheng. 2003. The effect of mycophenolate acid on hepatitis B virus replication in vitro. Hepatobiliary Pancreat Dis Int 2:410-3.
52. Yan, J. J., I. J. Su, P. F. Chen, C. C. Liu, C. K. Yu, and J. R. Wang. 2001. Complete genome analysis of enterovirus 71 isolated from an outbreak in Taiwan and rapid identification of enterovirus 71 and coxsackievirus A16 by RT-PCR. J Med Virol 65:331-9.
53. Yan, J. J., J. R. Wang, C. C. Liu, H. B. Yang, and I. J. Su. 2000. An outbreak of enterovirus 71 infection in Taiwan 1998: a comprehensive pathological, virological, and molecular study on a case of fulminant encephalitis. J Clin Virol 17:13-22.
54. Yang, T. T., L. M. Huang, C. Y. Lu, C. L. Kao, W. T. Lee, P. I. Lee, C. M. Chen, F. Y. Huang, C. Y. Lee, and L. Y. Chang. 2005. Clinical features and factors of unfavorable outcomes for non-polio enterovirus infection of the central nervous system in northern Taiwan, 1994-2003. J Microbiol Immunol Infect 38:417-24.