Publication: Binding of flavivirus nonstructural protein NS1 to C4b binding protein modulates complement activation
Issued Date
2011-07-01
Resource Type
ISSN
15506606
00221767
00221767
Other identifier(s)
2-s2.0-79960404180
Rights
Mahidol University
Rights Holder(s)
SCOPUS
Bibliographic Citation
Journal of Immunology. Vol.187, No.1 (2011), 424-433
Suggested Citation
Panisadee Avirutnan, Richard E. Hauhart, Pawit Somnuke, Anna M. Blom, Michael S. Diamond, John P. Atkinson Binding of flavivirus nonstructural protein NS1 to C4b binding protein modulates complement activation. Journal of Immunology. Vol.187, No.1 (2011), 424-433. doi:10.4049/jimmunol.1100750 Retrieved from: https://repository.li.mahidol.ac.th/handle/20.500.14594/12028
Research Projects
Organizational Units
Authors
Journal Issue
Thesis
Title
Binding of flavivirus nonstructural protein NS1 to C4b binding protein modulates complement activation
Abstract
The complement system plays a pivotal protective role in the innate immune response to many pathogens including flaviviruses. Flavivirus nonstructural protein 1 (NS1) is a secreted nonstructural glycoprotein that accumulates in plasma to high levels and is displayed on the surface of infected cells but absent from viral particles. Previous work has defined an immune evasion role of flavivirus NS1 in limiting complement activation by forming a complex with C1s and C4 to promote cleavage of C4 to C4b. In this study, we demonstrate a second mechanism, also involving C4 and its active fragment C4b, by which NS1 antagonizes complement activation. Dengue,West Nile, or yellow fever virus NS1 directly associated with C4b binding protein (C4BP), a complement regulatory plasma protein that attenuates the classical and lectin pathways. Soluble NS1 recruited C4BP to inactivate C4b in solution and on the plasma membrane. Mapping studies revealed that the interaction sites of NS1 on C4BP partially overlap with the C4b binding sites. Together, these studies further define the immune evasion potential of NS1 in reducing the functional capacity of C4 in complement activation and control of flavivirus infection. Copyright © 2011 by The American Association of Immunologists, Inc.