We have located links that may give you full text access.
JOURNAL ARTICLE
RESEARCH SUPPORT, NON-U.S. GOV'T
Killing effect of coexpressing cytosine deaminase and thymidine kinase on rat vascular smooth muscle cells.
Chinese Medical Journal 2004 October
BACKGROUND: Vascular smooth muscle cell (VSMC) proliferation following arterial injury plays a critical role in a variety of vascular proliferative disorders, such as atherosclerosis and restenosis after balloon angioplasty. Herpes simplex virus-thymidine kinase (HSV-TK)/ganciclovir (GCV) and E. coli cytosine deaminase (CD)/5-fluorocytosine (5-Fc) suicide gene systems have been successfully employed in cardiovascular gene therapy, respectively. We reasoned that coexpression of both HSV-TK with CD suicide genes would lead to increased cell killing. To test this imagine, the adenoviral vectors expressing TK and/or CD genes were developed and tested on vascular smooth muscle cells.
METHODS: Adenoviral vectors, including Ad-EF1alpha-CD-cytomegalovirus (CMV)-TK coexpressing both CD and TK double suicide genes, Ad-EF1alpha-CD and Ad-CMV-TK expressing CD and TK respectively, and control vector Ad-CMV-LacZ, were constructed and prepared with homologous recombination in RecA + E. coli cells. Integration and expression of CD and/or TK gene were identified by PCR and Western blot. Primary cultured VSMCs were infected at a multiplicity of infection (MOI) of 20 with exposure to their matching prodrugs 5-Fc and GCV. Cell mortality was measured by methyl thiazolyl tetrazolium (MTT) assays. Flow cytometry analysis was used to detect cell death. Apoptotic cells were analyzed using Hoechst 33342 fluorescence dye as a DNA probe. Genomic DNA cleavage of apoptotic VSMCs was tested by agarose gel electrophoresis.
RESULTS: Recombinant adenovirus expressing CD and/or TK suicide genes were successfully constructed. Both single and double suicide genes could be integrated into adenoviral genome and expressed. Cytotoxic effects of Ad-EF1alpha-CD-CMV-TK double suicide genes combined with 5-Fc and GCV were higher than those of Ad-CMV-TK and Ad-EF1alpha-CD single gene groups. The rate of cell survival was only (9 +/- 3)% in the Ad-EF1alpha-CD-CMV-TK group, but (37 +/- 3)% in the Ad-CMV-TK and (46 +/- 4)% in the Ad-EF1alpha-CD groups (P < 0.05). Flow cytometry analysis indicated that the killing mechanisms of the groups were different. Necrosis and apoptosis were involved in the mechanism of the double gene group. Based on the DNA stainability with Hoechst 33342, the apoptotic rates of VSMCs in the Ad-EF1alpha-CD-CMV-TK [(11.0 +/- 2.1)%] and Ad-CMV-TK [(12.0 +/- 2.2)%] groups were higher than those in Ad-CMV-LacZ [(1.2 +/- 0.11)%] and Ad-EF1alpha-CD [(5.0 +/- 1.8)%] groups (P < 0.05, respectively). DNA smear could be observed in both Ad-CMV-TK and Ad-EF1alpha-CD-CMV-TK groups after administration of prodrugs.
CONCLUSIONS: The killing effect on rat VSMCs mediated by adenoviral CD/TK double suicide genes is superior to that of single suicide gene. The killing mechanism of recombinant adenovirus coexpressing CD/TK double suicide genes is mainly through cytotoxic effect and apoptosis.
METHODS: Adenoviral vectors, including Ad-EF1alpha-CD-cytomegalovirus (CMV)-TK coexpressing both CD and TK double suicide genes, Ad-EF1alpha-CD and Ad-CMV-TK expressing CD and TK respectively, and control vector Ad-CMV-LacZ, were constructed and prepared with homologous recombination in RecA + E. coli cells. Integration and expression of CD and/or TK gene were identified by PCR and Western blot. Primary cultured VSMCs were infected at a multiplicity of infection (MOI) of 20 with exposure to their matching prodrugs 5-Fc and GCV. Cell mortality was measured by methyl thiazolyl tetrazolium (MTT) assays. Flow cytometry analysis was used to detect cell death. Apoptotic cells were analyzed using Hoechst 33342 fluorescence dye as a DNA probe. Genomic DNA cleavage of apoptotic VSMCs was tested by agarose gel electrophoresis.
RESULTS: Recombinant adenovirus expressing CD and/or TK suicide genes were successfully constructed. Both single and double suicide genes could be integrated into adenoviral genome and expressed. Cytotoxic effects of Ad-EF1alpha-CD-CMV-TK double suicide genes combined with 5-Fc and GCV were higher than those of Ad-CMV-TK and Ad-EF1alpha-CD single gene groups. The rate of cell survival was only (9 +/- 3)% in the Ad-EF1alpha-CD-CMV-TK group, but (37 +/- 3)% in the Ad-CMV-TK and (46 +/- 4)% in the Ad-EF1alpha-CD groups (P < 0.05). Flow cytometry analysis indicated that the killing mechanisms of the groups were different. Necrosis and apoptosis were involved in the mechanism of the double gene group. Based on the DNA stainability with Hoechst 33342, the apoptotic rates of VSMCs in the Ad-EF1alpha-CD-CMV-TK [(11.0 +/- 2.1)%] and Ad-CMV-TK [(12.0 +/- 2.2)%] groups were higher than those in Ad-CMV-LacZ [(1.2 +/- 0.11)%] and Ad-EF1alpha-CD [(5.0 +/- 1.8)%] groups (P < 0.05, respectively). DNA smear could be observed in both Ad-CMV-TK and Ad-EF1alpha-CD-CMV-TK groups after administration of prodrugs.
CONCLUSIONS: The killing effect on rat VSMCs mediated by adenoviral CD/TK double suicide genes is superior to that of single suicide gene. The killing mechanism of recombinant adenovirus coexpressing CD/TK double suicide genes is mainly through cytotoxic effect and apoptosis.
Full text links
Related Resources
Trending Papers
Heart failure with preserved ejection fraction: diagnosis, risk assessment, and treatment.Clinical Research in Cardiology : Official Journal of the German Cardiac Society 2024 April 12
Proximal versus distal diuretics in congestive heart failure.Nephrology, Dialysis, Transplantation 2024 Februrary 30
World Health Organization and International Consensus Classification of eosinophilic disorders: 2024 update on diagnosis, risk stratification, and management.American Journal of Hematology 2024 March 30
Efficacy and safety of pharmacotherapy in chronic insomnia: A review of clinical guidelines and case reports.Mental Health Clinician 2023 October
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app
All material on this website is protected by copyright, Copyright © 1994-2024 by WebMD LLC.
This website also contains material copyrighted by 3rd parties.
By using this service, you agree to our terms of use and privacy policy.
Your Privacy Choices
You can now claim free CME credits for this literature searchClaim now
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app