The alphavbeta5 integrin of hematopoietic and nonhematopoietic cells is a transduction receptor of RGD-4C fiber-modified adenoviruses.
Gene Ther
; 10(19): 1643-53, 2003 Sep.
Article
em En
| MEDLINE
| ID: mdl-12923563
ABSTRACT
Epithelial and endothelial cells expressing the primary Coxsackie virus B adenovirus (Ad) receptor (CAR) and integrin coreceptors are natural targets of human Ad infections. The fiber knob of species A, C, D, E and F Ad serotypes binds CAR by mimicking the CAR-homodimer interface, and the penton base containing arginine-glycine-aspartate (RGD) motifs binds with low affinity to alphav integrins inducing cell activation. Here, we generated seven different genetically modified Ad vectors with RGD sequences inserted into the HI loop of fiber knob. All mutants bound and infected CAR and alphav integrin-positive epithelial cells with equal efficiencies. However, the Ads containing two additional cysteines, both N and C terminals of the RGD sequence (RGD-4C), were uniquely capable of transducing CAR-less hematopoietic and nonhematopoietic human tumor cell lines and primary melanoma cells. Both binding and transduction of RGD-4C Ad were blocked by soluble RGD peptides. Flow cytometry of cell surface integrins and virus binding to CAR-less cells in the presence of function-blocking anti-integrin antibodies indicated that the alphavbeta5 integrin, but not alphavbeta3, alphaIIbbeta3 or beta1,alpha5 or alpha6-containing integrins served as a functional transduction receptor of the RGD-4C Ads. However, in cells with low levels of alphavbeta5 integrin, the function-blocking anti-alphavbeta5 antibodies were not effective, unlike soluble RGD peptides. Collectively, our data demonstrate that the alphavbeta5 integrin is a functional transduction receptor of RGD-4C Ads in the absence of CAR, and that additional RGD receptors are targets of these viruses. The RGD-4C vectors further extend the tropism of Ads towards potential human therapies.
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Base de dados:
MEDLINE
Assunto principal:
Células-Tronco Hematopoéticas
/
Terapia Genética
/
Leucemia
/
Integrinas
/
Adenoviridae
/
Receptores de Vitronectina
/
Vetores Genéticos
Limite:
Humans
Idioma:
En
Ano de publicação:
2003
Tipo de documento:
Article