Louis Pasteur's now famous phrase in describing scientific discoveries, "chance favors the prepared mind" is apt for the story of the discovery of the interleukin 2 (IL2) molecule. One often hears of the serendipity involved in scientific discovery, one of the most famous of which is the discovery of penicillin by Fleming. He noticed that bread mold growing on a discarded bacterial culture dish had a zone of absent bacterial growth surrounding it. Subsequently, Fleming teamed up with the chemist Florey and in a series of experiments, they painstakingly identified the active antibacterial chemical. Also, one often hears of a person "being in the right place at the right time" to make a discovery, which appears obvious once the discovery is made known. Sir Peter Medawar classified discoveries into "synthetic and analytic". A synthetic discovery is one that is made as if by accident, when there was no intention "to find" the thing discovered. Thus, in this instance the discovery amounts to the realization that something new has occurred. For if the investigator does not realize that a discovery has been made, it is as if nothing has happened. By comparison, an analytical discovery results from a direct quest to uncover and make known the characteristics of something that is suspected or known to exist, but is unknown as to the particulars.

Thus, the discovery of penicillin was both a synthetic discover by Fleming and an analytic discovery by Florey. The discovery that genes were comprised of nucleic acids by Avery, McCloud and McCarty would be an example of analytic discovery, in that their experiments were a focused effort to discover the chemical composition of the genetic material. Medawar pointed out that one often gets more credit for the synthetic than the analytic discovery. However, this is not always the case, in that another analytic discovery was More often than not, the preparation of the scientist in making a discovery is more important than luck. Ben Hogan, upon winning yet another US Open back in the 1950s was accused of being lucky with his putting by his radio interviewer. His response: "You know it's strange, but I have found that the more that I practice, the luckier I get". More...


The concept that interleukins mediate their effects on target cells by means of interacting with specific cellular receptors was first introduced with the discovery and characterization of the IL2 receptor (IL2R) in 1981. Subsequently over the course of the 1980s the structure and function of the three IL2R chains were elucidated, and many additional interleukin receptors were discovered. Thereafter, the 1990s focused on experiments that discovered and characterized the intracellular signaling molecules and transcription factors activated by the interleukin-receptor interactions.

These experiments transformed immunology from a descriptive science to one concerned with the molecular mechanisms of the control of the cells that mediate immune responses.

The next decade promises to be focused on the discovery of the genes activated by the cytokine-receptor interaction at the cell surface, while the next century should see the evolution of this basic knowledge into a new understanding, which hopefully can be translated to new therapies for disorders of the immune system. More...