A new Sendai virus vector deficient in the matrix gene does not form virus particles and shows extensive cell-to-cell spreading.
A new recombinant Sendai virus vector (SeV/DeltaM), in which the gene encoding matrix (M) protein was deleted, was recovered from cDNA and propagated in a packaging cell line expressing M protein by using a Cre/loxP induction system. The titer of SeV/DeltaM carrying the enhanced green fluorescent protein gene in place of the M gene was 7 x 10(7) cell infectious units/ml or more. The new vector showed high levels of infectivity and gene expression, similar to those of wild-type SeV vector, in vitro and in vivo. Virus maturation into a particle was almost completely abolished in cells infected with SeV/DeltaM. Instead, SeV/DeltaM infection brought about a significant increase of syncytium formation under conditions in which the fusion protein was proteolytically cleaved and activated by trypsin-like protease. This shows that SeV/DeltaM spreads markedly to neighboring cells in a cell-to-cell manner, because both hemagglutinin-neuraminidase and active fusion proteins are present at very high levels on the surface of cells infected with SeV/DeltaM. Thus, SeV/DeltaM is a novel type of vector with the characteristic features of loss of virus particle formation and gain of cell-to-cell spreading via a mechanism dependent on the activation of the fusion protein.
Inoue
Makoto
M
DNAVEC Research Inc., Tsukuba-shi, Ibaraki 305-0856, Japan. inoue@dnavec.co.jp
Tokusumi
Yumiko
Y
Ban
Hiroshi
H
Kanaya
Takumi
T
Shirakura
Masayuki
M
Tokusumi
Tsuyoshi
T
Hirata
Takahiro
T
Nagai
Yoshiyuki
Y
Iida
Akihiro
A
Hasegawa
Mamoru
M
D000818:Animals; D001921:Brain / Q000821:virology; D002459:Cell Fusion; D002460:Cell Line; D003588:Cytopathogenic Effect, Viral; D005822:Genetic Vectors; D005849:Gerbillinae; D015726:Giant Cells / Q000502:physiology; D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D051381:Rats; D029082:Sendai virus / Q000235:genetics / Q000472:pathogenicity* / Q000502:physiology; D014760:Viral Fusion Proteins / Q000235:genetics / Q000378:metabolism; D014763:Viral Matrix Proteins / Q000172:deficiency* / Q000235:genetics; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism; D014771:Virion / Q000378:metabolism*; D019065:Virus Assembly
D008164:Luminescent Proteins; C097020:M protein, Sendai virus; D014760:Viral Fusion Proteins; D014763:Viral Matrix Proteins; D014764:Viral Proteins; D049452:Green Fluorescent Proteins