Our novel antiviral host target discovery platform – The Zirus Gene Trap – represents a very cost effective and efficient platform for the discovery of targets and drugs to block viral infection.

Zirus scientists infect each cell in a colony of identical cells with a retrovirus, a small particle that causes a random insertion into the cell’s DNA. The insertion randomly disrupts the function of a single gene in a single cell into which it is inserted. Collectively, these unique cells create a library of cells each having a different single gene disrupted.

Importantly, cells that require the disrupted gene to survive will die and are not identified by the gene trap. Thus, genes that are essential to cell survival, and likely toxic if targeted with drugs, are selected against, and only the less toxic gene targets are identified.

Zirus scientists then infect every remaining cell with a virus that normally kills all cells, and identify those cells that survive the infection. Since all cells would normally be killed by the virus, the surviving cells must have survived due to a gene disruption of a human host RNA or protein that the virus must use, or hijack, to replicate. These specifically identified genes and their RNA and proteins, when turned off, prevent a particular virus from replicating.

Using this technique, we have discovered hundreds of human cellular targets essential for viral replication.

Above: The Zirus Gene Trap retrovirus infecting cells.