Multimerization of surfactant protein D, but not its collagen domain, is required for antiviral and opsonic activities related to influenza virus

Autor: John E. Heuser, Bruce Linders, Tesfaldet Tecle, Erika C. Crouch, Paul S. Kingma, Mitchell R. White, Kevan L. Hartshorn, Nilgun Kacak
Rok vydání: 2008
Předmět:
Zdroj: Journal of immunology (Baltimore, Md. : 1950). 181(11)
ISSN: 1550-6606
Popis: Surfactant protein D (SP-D) plays important roles in the initial innate defense against influenza A virus (IAV). The collagen domain of SP-D is probably critical for its homeostatic functions in vivo and has been implicated in the modulation of macrophage responses to SP-D-ligand complexes. For the current studies, we used a panel of rat SP-D mutants lacking all or part of the collagen domain to more specifically evaluate the contributions of this domain to viral interactions. SP-D multimers lacking the collagenous sequence efficiently neutralized Phil82 IAV, promoted neutrophil uptake of IAV, and also potentiated the IAV-induced neutrophil respiratory burst response. A dodecameric mutant with shortened collagenous arms showed enhanced viral aggregation and neuraminidase inhibition, and an increased capacity to inhibit a partially collectin-resistant strain of IAV. By contrast, truncated molecules lacking an N-terminal and collagen domain showed no detectable antiviral and opsonizing activity, despite preservation of lectin activity and detectable viral binding. Thus, multimerization, which is mediated by the N-peptide, is more important than the collagen domain for efficient viral neutralization and opsonization. However, the structure of the collagen domain significantly influences the anti-viral activity of multimerized forms of SP-D.
Databáze: OpenAIRE