title: A comitogenic serum glycoprotein in T lymphocyte activation.
abstract: The production of Interleukin-2 is induced in helper cells, probably of T-cell origin, after stimulation by Interleukin-1. PHA is known to induce production of Interleukin-1 and Interleukin-2 in human PBL. We observed that PHA-induced mitogenesis in PBL requires the presence of a 90-KD-serum glycoprotein, which we were able to distinguish from other known serum proteins of similar molecular weight. Its biological activity can be destroyed by removal of its sialic acid residues. Evidence presented in this paper indicates that the function of this protein is related to the induction of synthesis and/or release of Interleukin-2. The presence of PHA does not seem to be essential at the level of Interleukin-2 production; the glycoprotein is able to induce Interleukin-2 in cooperation with a soluble mediator, which is produced by adherent cells. This mediator causes T-cell mitogenesis in PBL, provided serum or the 90-KD glycoprotein is present in the culture. It is not able to support the growth of a CTL line. We suggest the name PHILIP (Plasmatic Human Interleukin-2-Inducing Protein) for the 90-KD molecule.
mesh_terms: D011232:Chemical Precipitation; D002846:Chromatography, Affinity; D002850:Chromatography, Gel; D006023:Glycoproteins / Q000096:biosynthesis / Q000097:blood* / Q000494:pharmacology; D006358:Hot Temperature; D006801:Humans; D007376:Interleukin-2 / Q000032:analysis / Q000096:biosynthesis / Q000494:pharmacology*; D007525:Isoelectric Focusing; D008213:Lymphocyte Activation; D008934:Mitogens / Q000032:analysis / Q000302:isolation & purification / Q000494:pharmacology*; D009439:Neuraminidase / Q000494:pharmacology; D013300:Streptokinase / Q000494:pharmacology; D013601:T-Lymphocytes / Q000276:immunology; D014357:Trypsin / Q000494:pharmacology
chemical_list: D006023:Glycoproteins; D007376:Interleukin-2; D008934:Mitogens; D009439:Neuraminidase; D013300:Streptokinase; D014357:Trypsin