Biomedical subjects

Kate L Dishart

Publications and source records attributed to Kate L Dishart.

3 recordsLinked to original sources

PubMed2004

Development of efficient viral vectors selective for vascular smooth muscle cells.

The vascular smooth muscle cell (SMC) is integral to the pathogenesis of neointimal formation associated with late vein graft failure, in-stent restenosis, and transplant arteriopathy. Viral vectors transduce SMC with low efficiency and hence, there is a need for improvement. We aimed to enhance the efficiency and selectivity of gene delivery to human SMC. Targeting ligands were identified using phage display on primary human saphenous vein SMC with linear and cyclic libraries. Two linear peptides, EYHHYNK (EYH) and GETRAPL (GET), were incorporated into the HI loop of adenovirus (Ad) fibers and the capsid protein of adeno-associated virus-2 (AAV-2). Exposure of human venous SMC to EYH-modified (but not the GET-modified) Ad vector resulted in a significant increase in transgene expression levels at short, clinically relevant exposure times. Similarly, the EYH-modified AAV vector resulted in enhanced gene transfer to human venous SMC but not endothelial cells in a time- and dose-dependent manner. The EYH-modified AAV vector also enhanced (up to 70-fold) gene delivery to primary human arterial SMC. Hence, incorporation of EYH into Ad and AAV capsids resulted in a significant and selective enhancement in transduction of SMC and has implications for improving local gene delivery to the vasculature.

Adenoviridae↗

PubMed2003

Transductional and transcriptional targeting of cancer cells using genetically engineered viral vectors.

Gene delivery vectors, including adenovirus (Ad) and adeno-associated virus (AAV), are inefficient and non-selective for cancer due to low levels of viral receptors with high levels on other tissues, including liver. We tested Ads and AAVs with the SIGYPLP-targeting peptide inserted into virus capsids for transduction in a panel of cancer cells. Six of twelve lines (C8161, PC-3, G-CCM, MKN-45, LnCAP and A549) were transduced, independently of native viral tropism. Furthermore the candidate cancer gene therapy promoter FLT-1 was active in three of these six cell lines. This offers the potential for dual targeting of selected cancer cells.

Adenoviridae↗

PubMed2003

Third-generation lentivirus vectors efficiently transduce and phenotypically modify vascular cells: implications for gene therapy.

Grafting of saphenous vein (SV) conduits into the arterial circulation triggers a number of adaptive pathological changes characterized by progressive medial thickening, neointima formation and accelerated atheroma. Previous studies have shown that modification of vein graft biology is possible by adenovirus (Ad)-mediated gene transfer, although gene expression is transient. Advancement of vascular gene therapy to the clinic is compromised by the lack of safe and efficient vector systems that provide sustained therapeutic gene delivery to the vasculature. Due to inadequacies of both Ad and adeno-associated virus (AAV) serotype-2 (AAV-2) systems, we have evaluated gene delivery to endothelial cells (ECs) and smooth muscle cells (SMCs) using alternate AAV serotypes and a third-generation vesicular stomatis virus glycoprotein-pseudotyped lentiviral system. Transduction of both primary human SV EC and SMC was lower using all alternate AAV serotypes compared to AAV-2. However, transduction of both cell types by lentivirus was efficient even at clinically relevant exposure times (15 min), was without toxicity and was promoter sensitive. Transduction levels at lower doses were further enhanced with the addition of the surfactant Poloxamer-407 (P-407). Direct comparison with Ad and AAV-2 confirmed the unique potential for this system. Moreover, we constructed and overexpressed the therapeutic gene tissue inhibitor of metalloproteinase-3 (TIMP-3) using lentivirus and demonstrated transgene production comparable to Ad with concomitant blockade of SMC migration and induction of cell death. We have demonstrated for the first time the potential for third-generation lentiviral vectors, but not alternate AAV serotypes, as efficient vascular gene delivery vectors.

Cardiovascular System↗