Antiviral activity of gliotoxin, gentian violet and brilliant green against Nipah and Hendra virus in vitro.
BACKGROUND
Using a recently described monolayer assay amenable to high throughput screening format for the identification of potential Nipah virus and Hendra virus antivirals, we have partially screened a low molecular weight compound library (>8,000 compounds) directly against live virus infection and identified twenty eight promising lead molecules. Initial single blind screens were conducted with 10 microM compound in triplicate with a minimum efficacy of 90% required for lead selection. Lead compounds were then further characterised to determine the median efficacy (IC50), cytotoxicity (CC50) and the in vitro therapeutic index in live virus and pseudotype assay formats.


RESULTS
While a number of leads were identified, the current work describes three commercially available compounds: brilliant green, gentian violet and gliotoxin, identified as having potent antiviral activity against Nipah and Hendra virus. Similar efficacy was observed against pseudotyped Nipah and Hendra virus, vesicular stomatitis virus and human parainfluenza virus type 3 while only gliotoxin inhibited an influenza A virus suggesting a non-specific, broad spectrum activity for this compound.


CONCLUSIONS
All three of these compounds have been used previously for various aspects of anti-bacterial and anti-fungal therapy and the current results suggest that while unsuitable for internal administration, they may be amenable to topical antiviral applications, or as disinfectants and provide excellent positive controls for future studies.
Aljofan
Mohamad
M
Australian Animal Health Laboratory, CSIRO Livestock Industries, Geelong, Australia. Mohamad.Aljofan@csiro.au
Sganga
Michael L
ML
Lo
Michael K
MK
Rootes
Christina L
CL
Porotto
Matteo
M
Meyer
Adam G
AG
Saubern
Simon
S
Moscona
Anne
A
Mungall
Bruce A
BA
D000818:Animals; D000998:Antiviral Agents / Q000737:chemistry / Q000494:pharmacology*; D002522:Chlorocebus aethiops; D004353:Drug Evaluation, Preclinical; D016679:Genome, Viral / Q000187:drug effects; D005840:Gentian Violet / Q000737:chemistry / Q000494:pharmacology*; D005912:Gliotoxin / Q000737:chemistry / Q000494:pharmacology*; D045404:Hendra Virus / Q000187:drug effects*; D015394:Molecular Structure; D045405:Nipah Virus / Q000187:drug effects* / Q000235:genetics; D000644:Quaternary Ammonium Compounds / Q000737:chemistry / Q000494:pharmacology*; D014709:Vero Cells
D000998:Antiviral Agents; D000644:Quaternary Ammonium Compounds; D005912:Gliotoxin; C006798:brilliant green; D005840:Gentian Violet