Immune function in patients with acute pancreatitis.

Background: The aim of this study was to clarify the relationship between the balance of T-helper (Th)1 and Th2 cytokines, and the numbers of CD4+ T and CD8+ T-cells, and was investigated, together with the plasma concentration of the antigen, an apoptosis marker, in patients with mild and acute pancreatitis (AP).

Methods: Plasma concentrations of soluble (s) CD4, sCD8, sIL-2-R, IL-12, IFN-gamma and sFas antigen were measured by ELISA, and CD4+ T, and CD8+ T lymphocyte counts were measured by flow cytometry.

Results: Both CD4+ T and CD8+ T-cells were reduced in number; in the severe cases the reduction in the former was more pronounced. A significant positive correlation was noted among the concentrations of sCD4, sIL-2-R and IL-12, and a significant positive correlation was also found between sCD4 and sFas. During the early stage of AP, the concentrations of sCD4, sCD8, sIL-2-R, IL-12 and IFN-gamma increased more in the severe cases compared with those who had milder symptoms; however, these increases were moderated during the clinical course.

Conclusion: We considered that these Th1 type CD4+ T cells probably induce the activation of macrophages and further pro-inflammatory reactions during the early stage of AP, as well as exerting direct cytotoxicity effects through Fas/Fas ligand expression.