Photoinactivation of vesicular stomatitis virus by a photodynamic agent, chlorophyll derivatives from silkworm excreta.
The efficacy of chlorophyll derivatives from silkworm excreta (CpD) in photodynamic antimicrobial chemotherapy (PACT) was studied. An enveloped animal virus, vesicular stomatitis virus (VSV), was used as a target organism. For CpD mediated PACT, the viruses in suspensions were treated with various doses of CpD (15-60 microg/ml) and visible red light was fixed at 120 mJ/cm(2). The antiviral effect of the CpD-PACT was measured 1 h after light irradiation by the extent of suppression of plaque forming units (pfu). In cultures inoculated with PACT-treated VSV, suppression of pfu was prominent and the results were demonstrated in a dose-dependent manner. In assays of RT-PCR, a single dose of 30 microg/ml CpD and light caused complete inhibition of viral RNA synthesis in the host cells, which agreed with the complete loss of plaque forming activity observed in pfu assays. An in vitro transcription assay for viral RNA using [3H]UTP and gel electrophoresis for the level of M protein was conducted. A gradual decrease in viral RNA transcription and an immediate decrease in M protein levels were observed in cells inoculated with the CpD-PACT-treated virus. These results demonstrated that CpD is a potential photodynamic antiviral agent, which causes inactivation of the matrix protein as well as transcription mechanisms involved in VSV replication.
Lim
Dae-Seog
DS
Department of Microbiology, College of Medicine, Yonsei University, CPO Box 8044, Seoul 120-752, South Korea.
Ko
Si-Hwan
SH
Kim
Seung-Jin
SJ
Park
Young-Jae
YJ
Park
Jeon-Han
JH
Lee
Won-Young
WY
D000818:Animals; D001483:Base Sequence; D012831:Bombyx / Q000378:metabolism*; D002460:Cell Line; D002734:Chlorophyll / Q000378:metabolism*; D017931:DNA Primers; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D008027:Light; D017319:Photosensitizing Agents / Q000494:pharmacology*; D012367:RNA, Viral; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014721:Vesicular stomatitis Indiana virus / Q000187:drug effects*
D017931:DNA Primers; D017319:Photosensitizing Agents; D012367:RNA, Viral; D002734:Chlorophyll