Activities of Acyclic Nucleoside Phosphonates against Orf Virus in Human and Ovine Cell Monolayers and Organotypic Ovine Raft Cultures

ABSTRACT Orf virus, a member of the Parapoxvirus genus, causes a contagious pustular dermatitis in sheep, goats, and humans. Previous studies have demonstrated the activity of (S)-1-[3-hydroxy-2-(phosphonomethoxy)propyl]cytosine (HPMPC; cidofovir; Vistide) against orf virus in cell culture and humans. We have evaluated a broad range of acyclic nucleoside phosphonates (ANPs) against several orf virus strains in primary lamb keratinocytes (PLKs) and human embryonic lung (HEL) monolayers. HPMPC, (S)-9-[3-hydroxy-2-(phosphonomethoxy)propyl]-2,6- diaminopurine (HPMPDAP), and (R)-9-[3-hydroxy-2-(phosphonomethoxy)propoxy]-2,4-diaminopyrimidine (HPMPO-DAPy) were three of the most active compounds that were subsequently tested in a virus yield assay with PLK and HEL cells by virus titration and DNA quantification. HPMPC, HPMPDAP, and HPMPO-DAPy were evaluated for their activities against orf virus replication in organotypic epithelial raft cultures from differentiated PLK cells. At the highest concentrations (50 and 20 μg/ml), full protection was provided by the three drugs, while at 5 μg/ml, only HPMPDAP and HPMPC offered partial protection. The activities of the three compounds in the raft culture system were confirmed by quantification of infectious virus and viral DNA. These findings provide a rationale for the use of HPMPC and other ANPs in the treatment of orf (contagious ecthyma) in humans and animals.

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Activities of Alkoxyalkyl Esters of Cidofovir (CDV), Cyclic CDV, and (S)-9-(3-Hydroxy-2-Phosphonylmethoxypropyl)Adenine against Orthopoxviruses in Cell Monolayers and in Organotypic Cultures

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01489-05 ◽

2006 ◽

Vol 50 (7) ◽

pp. 2525-2529 ◽

Cited By ~ 26

Author(s):

Ilya Lebeau ◽

Graciela Andrei ◽

Fabiana Dal Pozzo ◽

James R. Beadle ◽

Karl Y. Hostetler ◽

...

Keyword(s):

Vaccinia Virus ◽

Three Dimensional ◽

Cowpox Virus ◽

Organotypic Cultures ◽

Cell Monolayers ◽

Acyclic Nucleoside Phosphonates ◽

Acyclic Nucleoside

ABSTRACT The potencies of several alkoxyalkyl esters of acyclic nucleoside phosphonates against vaccinia virus and cowpox virus were evaluated in cell monolayers and three-dimensional epithelial raft cultures. Prodrugs were at least 20-fold more active than their parent compounds. Octadecycloxyethyl-(S)-9-(3-hydroxy-2-phosphonylmethoxypropyl)adenine emerged as the most potent derivative.

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Activities of Several Classes of Acyclic Nucleoside Phosphonates against Camelpox Virus Replication in Different Cell Culture Models

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00838-07 ◽

2007 ◽

Vol 51 (12) ◽

pp. 4410-4419 ◽

Cited By ~ 36

Author(s):

Sophie Duraffour ◽

Robert Snoeck ◽

Marcela Krečmerová ◽

Joost van Den Oord ◽

Rita De Vos ◽

...

Keyword(s):

Human Skin ◽

Ex Vivo ◽

Virus Yield ◽

Histological Evaluation ◽

Human Embryonic Lung ◽

3 Dimensional ◽

Culture Models ◽

Acyclic Nucleoside Phosphonates ◽

Acyclic Nucleoside ◽

Cell Culture Models

ABSTRACT Camelpox virus (CMLV) is the closest known virus to variola virus. Here we report on the anti-CMLV activities of several acyclic nucleoside phosphonates (ANPs) related to cidofovir [(S)-1-(3-hydroxy-2-phosphonomethoxypropyl)cytosine (HPMPC; Vistide)] against two CMLV strains, CML1 and CML14. Cytopathic effect (CPE) reduction assays performed with human embryonic lung fibroblast monolayers revealed the selectivities of the first two classes of ANPs (cHPMPA, HPMPDAP, and HPMPO-DAPy) and of the hexadecyloxyethyl ester of 1-{[(5S)-2-hydroxy-2-oxido-1,4,2-dioxaphosphinan-5-yl]methyl}-5-azacytosine (HDE-cHPMP-5-azaC), belonging to the newly synthesized ANPs, which are HPMP derivatives containing a 5-azacytosine moiety. The inhibitory activities of ANPs against both strains were also confirmed with primary human keratinocyte (PHK) monolayers, despite the higher toxicity of those molecules on growing PHKs. Virus yield assays confirmed the anti-CML1 and anti-CML14 efficacies of the compounds selected for the highest potencies in CPE reduction experiments. Ex vivo studies were performed with a 3-dimensional model of human skin, i.e., organotypic epithelial raft cultures of PHKs. It was ascertained by histological evaluation, as well as by virus yield assays, that CMLV replicated in the human skin equivalent. HPMPC and the newly synthesized ANPs proved to be effective at protecting the epithelial cells against CMLV-induced CPE. Moreover, in contrast to the toxicity on PHK monolayers, signs of toxicity in the differentiated epithelium were seen only at high ANP concentrations. Our results demonstrate that compounds belonging to the newly synthesized ANPs, in addition to cidofovir, represent promising candidates for the treatment of poxvirus infections.

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Morphogenesis of a New Human Herpes-Type Virus Isolate (Sasha Virus)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100073404 ◽

1973 ◽

Vol 31 ◽

pp. 592-593

Author(s):

R. F. Zeigel ◽

W. Munyon

Keyword(s):

Virus Isolate ◽

Calf Serum ◽

Uranyl Acetate ◽

Human Herpes ◽

Human Embryonic Lung ◽

Human Herpes Virus ◽

Intracytoplasmic Inclusions ◽

Hel Cells ◽

And Control

In continuing studies on the role of viruses in biochemical transformation, Dr. Munyon has succeeded in isolating a highly infectious human herpes virus. Fluids of buccal pustular lesions from Sasha Munyon (10 mo. old) uiere introduced into monolayer sheets of human embryonic lung (HEL) cell cultures propagated in Eagles’ medium containing 5% calf serum. After 18 hours the cells exhibited a dramatic C.P.E. (intranuclear vacuoles, peripheral patching of chromatin, intracytoplasmic inclusions). Control HEL cells failed to reflect similar changes. Infected and control HEL cells were scraped from plastic flasks at 18 hrs. of incubation and centrifuged at 1200 × g for 15 min. Resultant cell packs uiere fixed in Dalton's chrome osmium, and post-fixed in aqueous uranyl acetate. Figure 1 illustrates typical hexagonal herpes-type nucleocapsids within the intranuclear virogenic regions. The nucleocapsids are approximately 100 nm in diameter. Nuclear membrane “translocation” (budding) uias observed.

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