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- Gustafsson, Dan J, et al.
(författare)
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The Arg279Gln [corrected] substitution in the adenovirus type 11p (Ad11p) fiber knob abolishes EDTA-resistant binding to A549 and CHO-CD46 cells, converting the phenotype to that of Ad7p.
- 2006
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Ingår i: Journal of Virology. - 0022-538X .- 1098-5514. ; 80:4, s. 1897-905
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Tidskriftsartikel (refereegranskat)abstract
- The major determinant of adenovirus (Ad) attachment to host cells is the C-terminal knob domain of the trimeric fiber protein. Ad type 11p (Ad11p; species B2) in contrast to Ad7p (species B1) utilizes at least two different cellular attachment receptors, designated sBAR (species B adenovirus receptor) and sB2AR (species B2 adenovirus receptor). CD46 has recently been identified as one of the Ad11p attachment receptors. However, CD46 did not seem to constitute a functional receptor for Ad7p. Although Ad7p shares high knob amino acid identity with Ad11p, Ad7p is deficient in binding to both sB2AR and CD46. To determine what regions of the Ad11p fiber knob are necessary for sB2AR-CD46 interaction, we constructed recombinant fiber knobs (rFK) with Ad11p/Ad7p chimeras and Ad11p sequences having a single amino acid substitution from Ad7p. Binding of the constructs to A549 and CHO-CD46 BC1 isoform-expressing cells was analyzed by flow cytometry. Our results indicate that an Arg279Gln [corrected] substitution is sufficient to convert the Ad11p receptor-interaction phenotype to that of Ad7p and abolish sB2AR and CD46 interaction. Also a Glu279Arg substitution in Ad7p rFKs increases CD46 binding. Thus, the lateral HI loop of the Ad11p fiber knob seems to be the key determinant for Ad11p sB2AR-CD46 interaction. This result is comparable to another non-coxsackie-adenovirus receptor binding Ad (Ad37p), where substitution of one amino acid abolishes virus-cell interaction. In conjunction with previous results, our findings also strongly suggest that sB2AR is equivalent to CD46.
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| 2. |
- Segerman, Anna, et al.
(författare)
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Adenovirus types 11p and 35 attach to and infect primary lymphocytes and monocytes, but hexon expression in T-cells requires prior activation.
- 2006
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Ingår i: Virology. - : Elsevier BV. - 0042-6822 .- 1096-0341. ; 349:1, s. 96-111
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Tidskriftsartikel (refereegranskat)abstract
- Hematopoietic cells are attractive targets for gene therapy, but the conventional adenovirus (Ad) vectors, based on Ad5, transduce these cells inefficiently. One reason for low permissiveness of hematopoietic cells to infection by species C Ads appears to be inefficient attachment. Vectors pseudotyped with species B fibers are clearly more efficient at transducing hematopoietic cells than Ad5. To evaluate which Ad species B type(s) would be the most efficient vector(s) for primary T-cells, B-cells and monocytes, attachment to and entry of the species B1 serotypes 3p and 7p and the species B2 serotypes 11p and 35 into primary PBMCs was studied. Ad11p and Ad35 were the only serotypes to show efficient binding and for which uptake by PBMCs could be detected. Infection of PBMCs by Ad5, Ad11p and Ad35 was compared. Expression of Ad hexons was detected in stimulated PBMCs, most frequently in T-cells, and in unstimulated monocytes, although B-cells appear to be refractory to productive infection. Replication of Ad DNA was severely restricted in most PBMCs. Neither hexon expression nor genome replication could be detected in unstimulated lymphocytes, but FISH and a real-time PCR-based assay suggested that Ad11p and Ad35 DNA reach the nucleus. Activation thus appears to be required for T-cells to be permissive to Ad gene expression. In summary, there are substantial differences between Ad3p and Ad7p on the one hand and Ad11p and Ad35 on the other, in their ability to interact with PBMCs. Ad11p and Ad35 probably represent vectors of choice for these cell types.
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