Enhancing of measles virus infection by magnetofection
Introduction
Virus isolation from clinical specimens is crucial for the diagnosis and surveillance of viral diseases. For this purpose, concentration of virus is required if specimens contain only low titer of viruses. Ultracentrifugation and polyethylene glycol precipitation are used commonly to concentrate viruses. The former method needs special equipment, so that it is not suitable for screening purpose, while the latter method needs the removal of viscous solutions. Shell vial culture is used to enhance the detection level of virus antigens (Gleaves et al., 1984) and is only applicable to some large viruses such as cytomegalovirus.
Magnetofection has been developed for enhancing delivery of non-viral gene vectors as well as adenoviral or retroviral gene vectors to target cells. In this method, polyethylenimine-conjugated super-paramagnetic nanoparticles are mixed with adenoviral or retroviral vectors and targeted to cells under a magnetic field (Scherer et al., 2002).
In the present study, it is demonstrated that magnetofection enhances infection of measles virus belonging to Paramyxoviridae in both receptor-positive and -negative cells. Magnetofection could be useful for isolation of measles virus from clinical specimens.
Section snippets
Cells and viruses
Vero (African green monkey kidney) cells expressing a measles virus receptor, human SLAM (Vero/hSLAM), were grown in Dulbecco's modified essential medium supplemented with 10% fetal calf serum and 400 μg/ml of G418 for stable expression of human SLAM gene product after transfection (Tatsuo et al., 2000, Ono et al., 2001). HeLa (human cervical carcinoma) cells and B95a (adherent marmoset β-lymphoblastoid) cells (Kobune et al., 1990) were grown in Dulbecco's modified essential medium supplemented
CombiMag dose
In order to evaluate the effect of magnetofection on wild-type measles virus infection accurately, we used MV-EGFP and counted the number of EGFP-expressing cells after infection of Vero/hSLAM cells. The dose dependence of CombiMag on MV–EGFP infection was determined first. When 0–2 μl of CombiMag were mixed with 50 μl of MV–EGFP (5 × 102 TCID50) and inoculated to Vero/hSLAM cells in 96-well cluster plate, the number of EGFP-expressing cells increased in proportion to the amount of CombiMag (Fig. 1
Acknowledgements
We thank Dr. Y. Yanagi for providing Vero/hSLAM cells and MV–EGFP virus. This work was supported in part by the Ministry of Education, Culture, Sports, Science and Technology of Japan.
References (10)
- et al.
Specific inhibition of paramyxovirus and myxovirus replication by oligopeptides with amino acid sequences similar to those at the N-termini of the F1 or HA2 viral polypeptides
Virology
(1980) - et al.
Virus concentration using polyethyleneimine-conjugated magnetic beads for improving the sensitivity of nucleic acid amplification tests
J. Virol. Methods
(2003) - et al.
Rapid detection of cytomegalovirus in MRC-5 cells inoculated with urine specimens by using low-speed centrifugation and monoclonal antibody to an early antigen
J. Clin. Microbiol.
(1984) - et al.
SLAM(CD150)-independent measles virus entry as revealed by recombinant virus expressing green fluorescent protein
J. Virol.
(2002) - et al.
Marmoset lymphoblastoid cells as a sensitive host for isolation of measles virus
J. Virol.
(1990)
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