Immunohistochemical localization of interleukin-6 in human pancreatitis

The aim of the study was to identify immunohistochemically the localization of interleukin (IL)-6 in normal pancreas and in chronic pancreatitis (CP). Samples of tissues of normal pancreas (n=5) and CP (n=16), were verified histopathologically and then IL-6 was localized by immunohistochemical staining using the monoclonal antihuman IL-6 antibody and test LSAB2-HRP to visualize IL-6/Ab complexes. In slices of the pancreas, derived from patients with CP, a much stronger immunohistochemical reaction was noticed as compared with controls specimens. IL-6 was localized in exocrine, islet cells and ducts cells of the pancreas. Interestingly, this cytokine was detected in cytoplasm and very close to nucleus. Moreover, in cases of CP with inflammatory infiltration, there were a markedly stronger IL-6 expression, than that observed in specimens without infiltrate. In conclusion, the results presented herein clearly demonstrated a moderate and strong expression of IL-6 in exocrine and endocrine cells of patients with CP. These observations provide further support for the existence of local immune-pancreatic interactions.