The family Filoviridae includes Ebola virus and Marburg
virus, which are associated with sporadic outbreaks and high case fatality
rates. A maximum containment laboratory (Biosafety Level-4) is required
to study infectious forms of these viruses, and we have a full-suit BSL-4
laboratory at Texas Biomed. Our laboratory is interested in multiple
aspects of filovirus biology with a view to exploiting this knowledge to
further the development of vaccines and therapeutics.
Typically, RNA viruses have high spontaneous mutation rates
due to error prone RNA-dependent RNA polymerases. The consequences of
high spontaneous mutation and replication rates are populations composed of
heterogeneous swarms of related variant sequences, sometimes called quasispecies.
We are investigating the importance of this diversity to filovirus replication
and pathogenesis in vitro and in vivo and are particularly interested in
exploiting the mutation rate as a therapeutic mechanism. Specifically, we
work to understand the roles of the individual genotype populations in virus
infection; for example, in any Ebola virus population there is a mixture of
genotypes that appear to control the expression of different forms of the virus
glycoprotein (GP). The ratios of the genotypes is dynamic and changes
dependent on the origin species of cells used to propagate virus, and even in
an infected animal. These changes are certainly important for the
development of vaccines and therapeutic – that require animal models – but also
for viral pathogenesis.
Many of these studies exploit recent advances in
sequencing. We have several Illumina sequencing machines on our campus
and a miSeq in our laboratory. This system permits quantification of the
individual viral genotypes in a sample and we have developed techniques to
rapidly sequence whole viral genomes, including the 5’ and 3’ termini. We
are expanding the use of these machines into other areas including gene
expression and ribosomal profiling of cells and tissues infected with BSL-4 pathogens.
Alfson KJ, Beadles MW, and A. Griffiths*. (2014) A new approach to determining whole viral genomic sequences including termini using a single deep sequencing run. Journal of Virological Methods. 208 (1), 1-5
Alfson, Beadles, Menzie, Patterson, Carrion, and Griffiths*. (2015)Genetic Changes at the Glycoprotein Editing Site Associated with Serial Passage of Sudan Virus. J Infect Dis. pii: jiv216.
Alfson, Avena, Beadles, Staples, Nunneley, Ticer, Dick, Owston, Reed, Patterson, Carrion, and Griffiths*. (2015) Particle to plaque-forming unit ratio of Ebola virus influences disease course and survival in cynomolgus macaques. Journal of Virology. 89:6773-6781. PMCID: PMCID: PMC4468478 [Available on 2016-01-01]. Selected by journal for Spotlight feature
Cai, Parks, Wall, Stott, Stambaugh, Alfson, Griffiths, Mathies, Carrion, Patterson, Hawking, and Schmidt. (2015)Diagnosis of Ebola virus infection via amplification-free direct detection of single nucleic acids on a chip. Scientific Reports. 5:14494. 1-8.
Colgrove, Liu, Griffiths, Raja, DeLuca, Newman, Coen, and Knipe. (2015) History and genomic sequence analysis of the herpes simplex virus 1 KOS and KOS1.1 sub-strain. Virology. 487. 215-221
Alfson, Worwa, Carrion, and Griffiths*. (2015)Determination of the spontaneous mutation rate of Ebola virus and exploitation of this rate therapeutically. Journal of virology. 90(5):2345-55. Selected by journal for Spotlight feature
Cnops, van Griensven, Honko, Bausch, Sprecher, Hill, Colebunders, Johnson, Griffiths, Palacios, Kraft, Kobinger, Hewlett, Norwood, Sabeti, Jahrling, Formenty, Kuhn, and Arien. (2016) Essentials of filoviral load quantification. Lancet Infectious Diseases. 16(7): e134-e138
Sanabria-Solano, Gonzales, Richerioux, Bertrand, Griffiths, Langelier, and Pearson. (2016) Regulation of viral gene expression by the expression of herpes simplex virus 1 UL24 protein. Virology. 495: 148-160
Harden, Prasad, Griffiths, and Munger. (2017) Modulation of microRNA-mRNA target pairs by human papillomavirus 16 oncoproteins. mBio. 8(1); e02170-16
Du, Cai, Park, Wall, Stott, Alfson, Griffiths, Carrion, Patterson, Hawkins, Schmidt, and Mathies. (2017) Multiplexed efficient on-chop sample preparation and sensitive amplification-free detection of Ebola virus. Biosensors and Bioelectronics. 91; 489-496.
Alfson, Avena, Worwa, Carrion, Griffiths*. Development of a lethal intranasal exposure model of Ebola virus in the cynomolgus macaque. Accepted for publication in Viruses.