Molecular identification of the human tumor necrosis factor receptor on interleukin-2-stimulated peripheral blood lymphocytes

Abstract

The human tumor necrosis factor (TNF) receptor on interleukin (IL)-2-stimulated lymphocytes was characterized by binding and crosslinking techniques. The TNF receptor on IL-2-activated lymphocytes has an affinity of approximately 50 p m. Conventional crosslinking studies with the DSS analog bis(sulfosuccinimidyl) suberate demonstrated a ligand-receptor complex molecular weight of 106–108 kDa. Lectin precipitation experiments indicated that the receptor is a glycoprotein with an affinity for lectin isolated from Ricinus communis. Affinity crosslinking studies with the iodinateable, cleavable crosslinker sulfosuccinimidyl 2-( p-azido-salicylamido) ethyl 1,3′-dithiopropionate demonstrated that the TNF receptor, by itself, in the absence of bound ligand, has a molecular weight of approximately 90 kDa. Furthermore, these results indicate that the crosslinked TNF:TNF-receptor complexes observed at 104–108 kDa are composed of receptor and monomeric TNF.