The bimolecular structure of the interleukin 2 receptor

The structure of the receptors for interleukin 2 has recently been largely resolved, being composed of noncovalently linked 55 kDa and 75 kDa polypeptides. Here, Kendall Smith discusses how the low affinity binding sites present on these molecules combine to give rise to the single high affinity site found on normal T cells.