Binding of staphylococcal enterotoxin A (SEA) with human splenic lymphocytes.

1. The presence of specific binding of [125I]SEA with human splenocytes is established. 2. The association of toxin at 4 C is characterized by saturation, reversibility and a great affinity to a receptor (Kd = 4.0 x 10(-7) M). 3. The number of binding sites on a cell is equal to 6000. 4. At 23 C the binding of labelled toxin with a cell described by a biphasic curve. 5. Priming increases the association of SEA with the splenocytes and correspondingly increases the production level of gamma-interferon.