Open AccessA Morpholino Oligomer Targeting Highly Conserved Internal Ribosome Entry Site Sequence Is Able To Inhibit Multiple Species of Picornavirus
Author(s) -
Jeffrey K. Stone,
René Rijnbrand,
David A. Stein,
Yanxia Ma,
Yan Yang,
Patrick L. Iversen,
Raul Andino
Publication year - 2008
Publication title -
antimicrobial agents and chemotherapy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.07
H-Index - 259
eISSN - 1070-6283
pISSN - 0066-4804
DOI - 10.1128/aac.00011-08
Subject(s) - picornavirus , internal ribosome entry site , biology , coxsackievirus , poliovirus , virology , rhinovirus , enterovirus , picornaviridae , morpholino , virus , microbiology and biotechnology , rna , ribosome , cell culture , genetics , gene , gene knockdown
Members of the generaEnterovirus andRhinovirus (familyPicornaviridae ) cause a wide range of human diseases. An established vaccine is available only for poliovirus, and no effective therapy is available for the treatment of infections caused by any pathogenic picornavirus. Peptide-conjugated phosphorodiamidate morpholino oligomers (PPMO) are single-stranded DNA-like antisense agents that readily enter cells. A panel of PPMO was tested for their antiviral activities against various picornaviruses. PPMO targeting conserved internal ribosome entry site (IRES) sequence were highly active against human rhinovirus type 14, coxsackievirus type B2, and poliovirus type 1 (PV1), reducing PV1 titers by up to 6 log10 in cell cultures. Comparative sequence analysis led us to design a PPMO (EnteroX) targeting 22 nucleotides of IRES sequence that are perfectly conserved across greater than 99% of all human enteroviruses and rhinoviruses. EnteroX reduced PV1 replication in cell culture to an extent similar to that of other IRES-specific PPMO. Resistant PV1 arose in cell cultures after 12 passages in the presence of EnteroX and were found to have two mutations within the EnteroX target sequence. Nevertheless, cPVR transgenic mice treated once daily by intraperitoneal (i.p.) injection with EnteroX before and/or after i.p. infection with 3 × 108 PFU (three times the 50% lethal dose) of PV1 had an approximately 80% higher rate of survival than the controls. The viral titer in tissues taken at day 5 postinfection showed that animals in the EnteroX-treated group averaged over 3, 4, and 5 log10 less virus in the small intestine, spinal cord, and brain, respectively, than the amount in the control animals. These results suggest that EnteroX may have broad therapeutic potential against entero- and rhinoviruses.