Discovery of interleukin-2 (IL-2)
In the 1970s, researchers sought to define whether retroviruses are causative agents of human diseases, including cancers. In order to discover and study human retroviruses, researchers first needed to identify a way to grow and maintain T lymphocytes, or T-cells, long-term in the lab.
IRP researchers led by Robert Gallo, M.D., found a way to successfully grow T-cells in culture for more than nine months. They accomplished the feat by first stimulating lymphocytes with phytohemagglutinin, a protein found in plants, and then examining for the production of potential growth factors in the culture fluid. The team identified T-cell growth factor (TCFG), now known as interleukin-2 (IL-2).
The discovery and purification of IL-2 allowed researchers to grow T-cells and study their immunology, which led to the discovery of human T-cell leukemia virus (HTLV), the first retrovirus identified in humans.
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