The laboratory investigates the pathogenesis of viruses belonging to the tickborne encephalitis (TBE) virus complex of flaviviruses. Endemic throughout much of the northern hemisphere, these viruses can cause severe encephalitis, meningitis, or hemorrhagic fevers with relatively high mortality rates. Our research utilizes in vitro and animal models (mouse and tick) to examine the biology of acute and persistent infection in mammalian and arthropod systems. Understanding these aspects of virus biology will increase understanding of these important pathogens and may provide targets for the design of countermeasures. Methods employed include confocal microscopy, electron microscopy, electron cryotomography, immunohistochemistry, microarray analysis, nucleic acid sequencing, and molecular virology.

Figure 1. Reconstructed electron tomogram depicting endoplasmic reticulum (green), viral induced vesicles (blue), and virions (red) in Vero cells infected for 40 hours with a tickborne flavivirus. The vesicles are thought to form by budding into cisternae of the endoplasmic reticulum and to contain viral replication complexes, sequestering them from intracellular antiviral sensors.

Credit

NIAID

Figure 1. Reconstructed electron tomogram depicting endoplasmic reticulum (green), viral induced vesicles (blue), and virions (red) in Vero cells infected for 40 hours with a tickborne flavivirus. The vesicles are thought to form by budding into cisternae of the endoplasmic reticulum and to contain viral replication complexes, sequestering them from intracellular antiviral sensors.

Dr. Bloom received his M.D. in 1971 from Washington University School of Medicine in St. Louis, Mo., and then joined the Rocky Mountain Laboratories (RML) of NIAID in 1972 as a research associate. From 1975 to 1977, he was a postdoctoral fellow in the NIAID Laboratory of the Biology of Viruses on the NIH campus in Bethesda, MD. He returned to RML as a tenured investigator in 1977 and was a charter member of the Laboratory of Persistent Viral Diseases. He is a world expert in the molecular biology and pathogenesis of parvoviruses and is considered an authority in biocontainment. In 2004, Dr. Bloom’s research group changed its focus to the pathogenesis of tickborne flaviviruses. In 2002, Dr. Bloom was appointed associate director for RML in NIAID’s Division of Intramural Research, and among his duties have been program supervision of the permitting, construction, and staffing of NIAID's first biosafety level-4 facility. In 2008, Dr. Bloom was named associate director for science management for RML in NIAID’s Division of Intramural Research. He has also served as acting chief of the NIAID new Laboratory of Virology and acting chief of the NIAID Laboratory of Human Bacterial Pathogenesis.

Luwanika Mlera, Ph.D., Visting Fellow; Wessam Melik, Ph.D., Visiting Fellow; Danielle Offerdahl, M.S., Microbiologist, Technician; Jennifer Lam, Post-baccalaureate IRTA; Niall Gallagher-Clancy, Summer Intern; Madison Channer, Student IRTA

Mlera L, Melik W, Bloom ME. The role of viral persistence in flavivirus biology. Pathog Dis. 2014 Apr 15. Epub ahead of print.

Offerdahl DK, Dorward DW, Hansen BT, Bloom ME. A three-dimensional comparison of tick-borne flavivirus infection in mammalian and tick cell lines. PLoS One. 2012;7(10):e47912.

Taylor RT, Lubick KJ, Robertson SJ, Broughton JP, Bloom ME, Bresnahan WA, Best SM. TRIM79α, an interferon-stimulated gene product, restricts tick-borne encephalitis virus replication by degrading the viral RNA polymerase. Cell Host Microbe. 2011 Sep 15;10(3):185-96.

McNally KL, Mitzel DN, Anderson JM, Ribeiro JM, Valenzuela JG, Myers TG, Godinez A, Wolfinbarger JB, Best SM, Bloom ME.Differential salivary gland transcript expression profile in Ixodes scapularis nymphs upon feeding or flavivirus infection. Ticks Tick Borne Dis. 2012 Feb;3(1):18-26.

Laurent-Rolle M, Boer EF, Lubick KJ, Wolfinbarger JB, Carmody AB, Rockx B, Liu W, Ashour J, Shupert WL, Holbrook MR, Barrett AD, Mason PW, Bloom ME, García-Sastre A, Khromykh AA, Best SM. The NS5 protein of the virulent West Nile virus NY99 strain is a potent antagonist of type I interferon-mediated JAK-STAT signaling. J Virol. 2010 Apr;84(7):3503-15.

Risi GF, Bloom ME, Hoe NP, Arminio T, Carlson P, Powers T, Feldmann H, Wilson D. Preparing a community hospital to manage work-related exposures to infectious agents in BioSafety level 3 and 4 laboratories. Emerg Infect Dis. 2010 Mar;16(3):373-8.