[Alterations of lymphocyte subsets and indicators of immune suppression in patients with acute pancreatitis]

Assessment of changes in lymphocyte number and some indicators of the immune suppression (frequency of regulatory T cells (Treg), the level of expression of CTLA-4 (cytolytic T lymphocyte-associated antigen 4) and interleukin (IL)-10) in patients with acute pancreatitis (AP).

Peripheral blood samples of 21 patients with AP (including 11 patients with pancreatic necrosis (PN)) were studied for analysis of lymphocyte subsets and 11 blood samples of healthy donors were estimated as control. Evaluation of the expression of molecules of lymphocytes was carried out by flow cytometry.

It was found that percentage of CD3+ T cells and their subpopulation of CD4+ T-helper cells in patients with AP were decreased as compared to the control group. Substantial changes were observed in patients with PN: together with decrease in the number of T cells, CD19+ B cells and CD4+ CD25+ activated T-helper cells were also reduced, and the percentage of CD8+ T cells was higher. The immunoregulatory index (CD4+/CD8+) was lower in the group of patients, than in control group. The frequency of Treg cells (CD4+ CD25hi and CD4+ CD25+ CD127lo) was higher in patients with AP than in the control. The expression level of the inhibitory molecule CTLA-4 in the subset of CD4+ CD25hi Treg cells in patients with AP was also increased. Moreover, it was found that the expression level of anti-inflammatory cytokine IL-10 was higher in T-helper cells from patients with AP.

Changes in cellular immunity (especially patients with PN) werefound in patients wish AP. These changes may indicate the possible development of secondary immunodeficiency. This is probably related to the generation of immune suppression, since the values of the investigated parameters (frequency of Treg cells, the expression of CTLA-4 and IL-10) in patients with AP were higher than in controls.