On Jun. 1, 2000, scientists at the Oklahoma Medical Research Foundation (OMRF) announced the discovery of a new interferon-like substance they named “limitin” because of its ability to limit tumor cell growth.

Limitin is partially similar in structure to the type I interferons, naturally occurring proteins first discovered for their ability to curtail viral replication. However, limitin was discovered in an unexpected way and may have unique biological activities.

Limitin arrests the division of some mouse cell tumors in culture and causes other tumors to die. This discovery and an initial description of limitin activities will be described in the June issue of Nature Medicine.