Topographical associations between islet endocrine cells and duct epithelial cells in the adult human pancreas.
OBJECTIVE
The pancreatic ducts, endocrine islets and exocrine acini are three functionally related components. From birth to adulthood, the islets and ducts are regarded as independent entities. The objective of this study is to investigate the topographical associations between the islet endocrine cells and duct epithelial cells in the adult human pancreas.


METHODS
Panels of immunomarkers for the exocrine acinar cells (amylase), duct cells [cytokeratin 19 (CK19)], endocrine cells (chromogranin A, neurone specific enolase, synaptophysin) and islet hormones (glucagon, insulin, somatostatin, pancreatic polypeptide) were applied to sequential pancreatic tissue sections obtained from autopsy specimens of 10-nondiabetic human adults. Double immunofluorescent staining with CK19 and islet hormones was performed to confirm the islet to duct interrelationship.


RESULTS
Sequential sectioning and immunostaining showed that 45% of the 172 islets examined appeared as single endocrine cell units or small clusters of < 10 endocrine cells on at least one plane of section. A topographical association was found between the islet endocrine cells and duct epithelial cells. Topographical associations with CK 19-stained duct cells occurred in 10.9% of the islet insulin-containing beta-cells and in 8.9% of the islet glucagon-producing alpha-cells. The frequency of topographical associations increased toward the more distally located duct systems. The CK19-stained duct cells and amylase-labelled acinar cells were less frequently in association with other islet hormone-producing cells.


CONCLUSIONS
Topographical associations between islet endocrine cells and pancreatic duct cells are frequent in adult human pancreas. The islet-duct association suggests possible functional interactions between the two interrelated pancreatic compartments.
Zhao
Hai-Lu
HL
Department of Medicine and Therapeutics, the Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong SAR, China. zhaohailu@cuhk.edu.hk
Sui
Yi
Y
Guan
Jing
J
Lai
Fernand M M
FM
Gu
Xue-Mei
XM
He
Lan
L
Zhu
Xun
X
Rowlands
Dewi K
DK
Xu
Gang
G
Tong
Peter C Y
PC
Chan
Juliana C N
JC
D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000378:metabolism; D055098:Endocrine Cells / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D004847:Epithelial Cells / Q000166:cytology* / Q000276:immunology / Q000378:metabolism; D005260:Female; D005934:Glucagon / Q000378:metabolism; D006801:Humans; D007328:Insulin / Q000378:metabolism; D007515:Islets of Langerhans / Q000166:cytology* / Q000276:immunology / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D010179:Pancreas / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D010183:Pancreatic Ducts / Q000166:cytology* / Q000276:immunology / Q000378:metabolism
D015415:Biomarkers; D007328:Insulin; D005934:Glucagon