Human islets of Langerhans express Fas ligand and undergo apoptosis in response to interleukin-1beta and Fas ligation.

  1. A C Loweth,
  2. G T Williams,
  3. R F James,
  4. J H Scarpello and
  5. N G Morgan
  1. Department of Biological Sciences, Keele University, Staffs, UK.

    Abstract

    IDDM results from a progressive loss of pancreatic beta-cells that, in humans, may be triggered by a combination of genetic and environmental factors. Recently, attention has been focused on the hypothesis that the loss of beta-cells is initiated by inappropriate induction of apoptosis. We now demonstrate that human islets of Langerhans undergo apoptosis upon exposure to interleukin-1beta. The cytokine also sharply increases the number of cells that enter apoptosis on treatment with a stimulatory anti-Fas antibody. Western blotting and immunocytochemistry clearly show for the first time that human pancreatic beta-cells normally express Fas ligand. The results suggest that human islet cells are primed to undergo apoptosis by interleukin-1beta and that this involves the close association between cell-surface Fas and its ligand.

    | Table of Contents