Researchers Identify Protein that Fights West Nile Virus
New Haven, Conn. – Yale and 㽶Ƶ scientists have
identified a protein that is critical in fighting mosquito-borne
West Nile Virus in mice. This finding could have therapeutic
implications for controlling the potentially deadly virus in
humans. The study appears in the Advance Online Publication of
Nature Immunology.
Researchers studied the role of caspase-12, a protein that
activates secretion of substances that are part of the body’s
immune response. Caspase-12’s function in fighting bacterial
infection has been studied before, but its role in viral immunity
has not.
The Yale-McGill team found that caspase-12 regulated the signaling
of RIG-I, a protein of the immune system that detects viral
infection by recognizing its genetic components. This recognition
pattern is necessary to trigger the immune system’s response to
West Nile Virus.
“Mice without caspase-12 protein died more rapidly from West Nile
virus infection and had higher levels of virus than normal mice,”
explained co-author Erol Fikrig, M.D., professor of epidemiology,
public health and microbial pathogenesis at Yale School of Medicine
and a Howard Hughes Medical Institute investigator.
West Nile Virus has spread rapidly through North America over the
past decade, and can be life-threatening to those with susceptible
immune systems.
The team’s findings open possible avenues of future research on
whether the human immune system can be regulated in the same way,
noted co-author Maya Saleh, Ph.D., assistant professor of medicine
at 㽶Ƶ and medical scientist in the Division of
Critical Care at the Research Institute of the 㽶Ƶ
Health Centre. “Our results now set the stage for the development
of pharmacological compounds to boost the activity of caspase-12 in
promoting virus elimination,” Saleh said. “These findings have
significant potential to be translated into therapies.”
Other authors are Penghua Wang, Alvaro Arjona, Yue Zhang, Jianfeng
Dai and Long Yang of Yale School of Medicine, Hameeda Sultana of
Yale and a Howard Hughes Medical Institute Investigator, Philippe
M. LeBlanc and Karine Doiron of 㽶Ƶ Department of
Microbiology and Immunology.
The study was funded by grants from the National Institutes of
Health, the Howard Hughes Medical Institute, the Northeast
Biodefense Center, the Canadian Institutes for Health Research and
the Burroughs Wellcome Fund.