The structural integrity of the islet in vitro: The effect of incubation temperature

Citation
A. Ilieva et al., The structural integrity of the islet in vitro: The effect of incubation temperature, PANCREAS, 19(3), 1999, pp. 297-303
Citations number
52
Categorie Soggetti
da verificare
Journal title
PANCREAS
ISSN journal
08853177 → ACNP
Volume
19
Issue
3
Year of publication
1999
Pages
297 - 303
Database
ISI
SICI code
0885-3177(199910)19:3<297:TSIOTI>2.0.ZU;2-M
Abstract
The purpose of this study was to examine the effect of incubation temperatu re on the structural integrity of the islet during culture. Islets were iso lated from the pancreas of the Syrian golden hamster and cultured in a coll agen gel for less than or equal to 12 days at 24 degrees C or 37 degrees C. At 24 degrees C, cells in the islet periphery died, leading to a complete disintegration of the mantle region in 37.4 +/- 5.6% of the islets. In comp arison, at 37 degrees C, few islets exhibited mantle disintegration (p < 0. 001). Insulin immunoreactivity was distributed nonhomogeneously in islets a t 24 degrees C, and the intensity of the staining, by using a semiquantitat ive scale (0-3), was +1. Islets cultured at 37 degrees C had a normal homog eneous distribution of insulin immunoreactivity with a score of +3. As the pancreas is a complex gland composed of different cell types, and cell-cell interactions are known to be important in the maintenance of cell survival , additional experiments were repeated to include the coculture of islets w ith duct epithelial cells. The proportion of islets that developed mantle d isintegration was now reduced to 2.5 +/- 0.3% (p < 0.001), comparable to th at seen at 37 degrees C. Similar results were obtained for islets cultured in the presence of duct-conditioned medium (DCM). Together with the preserv ation of the islet mantle, islets cultured in the presence of duct epitheli al cells or DCM had a normal homogeneous distribution of insulin immunoreac tivity, with a staining intensity of +3. We conclude that incubation temper ature has a profound effect on the structural integrity of islets, and that the detrimental effects of low-temperature culture can be mitigated by coc ulture of islets with secretory products derived from pancreatic ductal cel ls. These data provide evidence for a trophic relation between pancreatic i slets and ductal epithelium.