Flow cytometry resonance energy transfer suggests an association between low-affinity interleukin 2 binding sites and HLA class I molecules.

Using flow cytometry energy transfer we have studied the sterical proximity of interleukin 2 receptors and the heavy chain of the major histocompatibility complex at the surface of normal lymphocytes. Our data suggest that class I molecules may be part of a low-affinity interleukin 2 receptor multimolecular complex, where the MHC class I heavy chain is in close proximity to the actual interleukin 2 binding site, in contrast to the light chain (beta 2-microglobulin).