Quantitative characterization of cell transduction by HSV-1 amplicons using flow cytometry and real-time PCR
Autor: | Richard Wade-Martins, Yasser Elsherbini, Leonard W. Seymour, Mark Stevenson |
---|---|
Jazyk: | angličtina |
Rok vydání: | 2016 |
Předmět: |
Green Fluorescent Proteins
Herpesvirus 1 Human Biology medicine.disease_cause Origin of replication Polymerase Chain Reaction Virus Flow cytometry law.invention Transduction (genetics) law Genes Reporter Transduction Genetic Virology Chlorocebus aethiops medicine Animals Vero Cells Polymerase chain reaction medicine.diagnostic_test Amplicon Flow Cytometry Molecular biology Herpes simplex virus Real-time polymerase chain reaction |
Popis: | Herpes simplex virus type 1 (HSV-1) amplicon preparations are usually quantified as transducing units/ml (TU/ml), with little information on genomic copy/TU ratios. In the present study, two HSV-1 amplicons expressing enhanced green fluorescent protein (EGFP) were analysed by quantitative PCR (qPCR) and transducing activity to obtain genomic copy/TU ratios. One vector (pHSV-GL) contains the HSV-1 packaging signal (pac) and origin of replication (oriS) and the other (pHSV/EBV-GL) includes Epstein-Barr virus (EBV) episomal maintenance elements. The pHSV-GL and pHSV/EBV-GL amplicons were prepared at titres of 7.55x10(7) and 7.24x10(7)TU/ml, containing 2.56x10(9) and 1.33x10(9) genomic copies/ml respectively. This produced preliminary estimates of genomic copy/TU ratios of 34:1 and 18:1. However standard transduction conditions did not deplete fully the supernatant of transducing particles since the same supernatant was subsequently able to achieve 25% the initial transduction efficiency, although centrifugation of amplicon particles onto cells improved infectivity by 1.8-fold. Finally, qPCR analysis of FACS-purified EGFP-expressing cells showed the presence of approximately 3 amplicon genomes/transduced cell, independent of the infection dose. Accordingly, the initial estimated genomic copy/TU ratio for pHSV-GL was revised to 6.3:1. Measuring the genomic copy/TU ratios is an important parameter for comparing the quality of amplicon preparations and standardizing experimental conditions. |
Databáze: | OpenAIRE |
Externí odkaz: |