Differential expression of chemokines in normal pancreas and in chronic pancreatitis

Background & Aims: Cellular infiltrates are present already in early stages of chronic pancreatitis. The mechanisms responsible for their recruitment are unknown. Hence, we determined the differential expression of chemokine genes and their cellular sources in normal and affected pancreatic tissues. Methods: Pancreatic tissues from 23 patients with chronic pancreatitis and from 4 normal controls were subjected to in situ hybridization for detecti ng messenger RNA (mRNA) of the chemokine genes interleukin 8, ENA-78, MIG, MCP-1, and 1-309. Results: Normal pancreatic tissues lack cells expressing; mRNA for IL-8, ENA-78, MIG, and MCP-1. In contrast, pancreatic lobuli with mild to moderate signs of tissue alterations strongly expressed MCP-1 mRNA in centroacinar ducts, endothelia, fibroblasts, macrophages, T cells, and occasionally in nerves. Interleukin 8 and ENA-78 mRNA is preferentially det ected in centroacinar ducts of pancreatic lobuli with more advanced alterat ions. Variable numbers of pancreas-infiltrating T cells express MIG mRNA. 1 -309 mRNA, however, is consistently observed in normal acini and in tissue with mild to moderate signs of tissue alterations. Conclusions: The observe d differential expression of distinct chemokine genes in pancreatic parench yma and infiltrates from patients with chronic pancreatitis strongly sugges ts an involvement of distinct chemokines in the initiation and perpetuation of disease.