Homologous but Not Heterologous Contact Increases the Insulin Secretion of Individual Pancreatic B-cells

Exp Cell Res. 1989 Sep;184(1):72-80. doi: 10.1016/0014-4827(89)90365-0.

Abstract

To assess whether and how specifically contact influences the functioning of differentiated cells, we have studied the secretion of adult pancreatic B-cells as a function of aggregation to either homologous B-cells or other heterologous endocrine islet cell types, all present in a mixed cell suspension. Using an immunological plaque assay for insulin, we have quantitated the proportion of single and aggregated B-cells inducing the formation of a hemolytic plaque (a reflection of the size of the secreting cell population) and the area of these plaques (a reflection of the hormonal output of individual cells or aggregates) after a 30-min stimulation by 16.7 mM glucose. By taking into account the number of B-cells within the aggregates, we have calculated from these data the insulin output on a per B-cell basis. We show here that the homologous contact between companion B-cells promotes the recruitment of secreting B-cells and increases their individual secretion of insulin twofold over that of single B-cells. By contrast, heterologous B- to non-B-cell contact was not effective in enhancing the recruitment of secreting B-cells and in promoting their individual secretion. These findings show that a highly differentiated cell function, such as insulin secretion, is controlled specifically by homologous cell to cell contacts.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Adhesion
  • Cell Communication
  • Glucose / pharmacology
  • In Vitro Techniques
  • Insulin / metabolism*
  • Insulin Secretion
  • Islets of Langerhans / cytology
  • Islets of Langerhans / metabolism*
  • Rats
  • Rats, Inbred Strains
  • Secretory Rate / drug effects

Substances

  • Insulin
  • Glucose