A human DNA enzyme called APOBEC3B is capable of mutating and killing two viruses— Epstein-Barr virus (EBV) and Kaposi’s sarcoma herpesvirus (KSHV)—as it invades and replicates inside the body. However, researchers discovered that each virus can produce defense proteins (BORF2 and ORF61, respectively) that bind directly to this enzyme.
The team—from the University of Minnesota, the Howard Hughes Medical Institute, and the University of Toronto—used CRISPR/Cas9-mediated genome engineering to delete EBV’s defense protein, rendering APOBEC3B unable to mutate and kill the viral DNA and directing away from sites of virus replication.
“People infected with EBV or KSHV will have the virus for life,” said Adam Cheng of the University of Minnesota Medical School. “In most cases, the virus will remain dormant. However, sometimes these viruses can reactivate and lead to abnormal, cancerous cell growth. But now, in the wake of our research, data suggests it may be possible to suppress the virus indefinitely.”