Exploring the Use of Genetic Engineering to Treat Equine Infectious Anemia

SUMMARY: Researchers will use the CRISPR-Cas9 system to edit viral DNA out of cells to determine if this methodology could provide a new treatment/cure for equine infectious anemia.

THE PROBLEM: Equine infectious anemia (EIA), also known as “swamp fever,” is a serious and lifelong disease in horses caused by a virus named Equine Infectious Anemia Virus (EIAV). Once a horse is infected, the virus hides inside certain white blood cells (known as monocytes and macrophages) by inserting its genetic material into the horse’s DNA. This allows the virus to stay in the body and keep reproducing. There is currently no cure or vaccine, so infected horses must either be euthanized or kept in strict isolation for life.

THE PROJECT: This pilot study will test a new and innovating approach using CRISPR-Cas9 technology, often described as “molecular scissors.” CRISPR-Cas9 can cut out specific pieces of DNA, and the goal here is to remove the virus’s DNA from infected horse cells without harming the cells. The research project has two main parts. First, the team will create small pieces of RNA, called guide RNAs, that will help the CRISPR-Cas9 scissors find and cut the virus’s DNA within horse cells. These will be tested in lab-grown horse dermal cells already infected with the virus. The most effective guides will then be combined to make the DNA removal more efficient. In the second step, the best guide RNA combination will be used in immune cells collected from healthy horses, which will be infected with the virus in the lab. The team will test whether CRISPR-Cas9 can fully remove the virus’s DNA, stopping the cell from making more virus, and avoid any harmful effects on the cells.

POTENTIAL IMPACT: If successful, this method could lead to new treatments for EIA, improve horse welfare, and help guide research into fighting other animal viruses.