Isolation, purification, and partial characterization of suppressin, a novel inhibitor of cell proliferation

Academic Article


  • Pituitary tissues were investigated for the presence of regulatory molecules that would alter the function of lymphoid cells. A novel endogenous polypeptide inhibitor of basal and mitogen-stimulated splenocyte DNA synthesis and proliferation, suppressin, was isolated from bovine pituitary glands. Suppressin is a potent inhibitor of basal and mitogen-stimulated splenocyte proliferation at picomole and nanomole concentrations with 50% inhibition occurring 2.8 x 10-9 M. Suppressin was purified to apparent homogeneity using sequential (NH4)2SO4 precipitation, ion-exchange chromatography, and preparative native gel electrophoresis. Biochemical characterizations of suppressin showed that this inhibitory molecule was a monomeric polypeptide with (i) a M(r) = 63,000 and (ii) a pI of 8.1. Finally, metabolic labeling studies using a rat pituitary tumor cell line, GH3, showed that suppressin was synthesized de novo and secreted by these cells.
  • Authors

    Published In

    Pubmed Id

  • 12421826
  • Author List

  • LeBoeuf RD; Burns JN; Bost KL; Blalock JE
  • Start Page

  • 158
  • End Page

  • 165
  • Volume

  • 265
  • Issue

  • 1