Inhibition, escape, and attenuated growth of severe acute respiratory syndrome coronavirus treated with antisense morpholino oligomers.
The recently emerged severe acute respiratory syndrome coronavirus (SARS-CoV) is a potent pathogen of humans and is capable of rapid global spread. Peptide-conjugated antisense morpholino oligomers (P-PMO) were designed to bind by base pairing to specific sequences in the SARS-CoV (Tor2 strain) genome. The P-PMO were tested for their capacity to inhibit production of infectious virus as well as to probe the function of conserved viral RNA motifs and secondary structures. Several virus-targeted P-PMO and a random-sequence control P-PMO showed low inhibitory activity against SARS coronavirus. Certain other virus-targeted P-PMO reduced virus-induced cytopathology and cell-to-cell spread as a consequence of decreasing viral amplification. Active P-PMO were effective when administered at any time prior to peak viral synthesis and exerted sustained antiviral effects while present in culture medium. P-PMO showed low nonspecific inhibitory activity against translation of nontargeted RNA or growth of the arenavirus lymphocytic choriomeningitis virus. Two P-PMO targeting the viral transcription-regulatory sequence (TRS) region in the 5' untranslated region were the most effective inhibitors tested. After several viral passages in the presence of a TRS-targeted P-PMO, partially drug-resistant SARS-CoV mutants arose which contained three contiguous base point mutations at the binding site of a TRS-targeted P-PMO. Those partially resistant viruses grew more slowly and formed smaller plaques than wild-type SARS-CoV. These results suggest PMO compounds have powerful therapeutic and investigative potential toward coronavirus infection.
Neuman
Benjamin W
BW
The Scripps Research Institute, Division of Virology, Department of Neuropharmacology, La Jolla, CA 92037, USA. bneuman@scripps.edu
Stein
David A
DA
Kroeker
Andrew D
AD
Churchill
Michael J
MJ
Kim
Alice M
AM
Kuhn
Peter
P
Dawson
Philip
P
Moulton
Hong M
HM
Bestwick
Richard K
RK
Iversen
Patrick L
PL
Buchmeier
Michael J
MJ
D020121:5' Untranslated Regions; D000818:Animals; D000998:Antiviral Agents / Q000494:pharmacology*; D001483:Base Sequence; D002522:Chlorocebus aethiops; D003588:Cytopathogenic Effect, Viral; D015195:Drug Design; D024882:Drug Resistance, Viral; D008969:Molecular Sequence Data; D009025:Morpholines / Q000494:pharmacology*; D060172:Morpholinos; D009154:Mutation; D009690:Nucleic Acid Conformation; D010455:Peptides; D045473:Severe acute respiratory syndrome-related coronavirus / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development; D012692:Serial Passage; D045169:Severe Acute Respiratory Syndrome; D014158:Transcription, Genetic / Q000187:drug effects; D014709:Vero Cells
D020121:5' Untranslated Regions; D000998:Antiviral Agents; D009025:Morpholines; D060172:Morpholinos; D010455:Peptides