T lymphocyte cytokine profile at a single cell level in alveolar Echinococcosis.

The metacestode Echinococcus multilocularis causes a life-threatening disease in humans, named alveolar echinococcosis (AE). A comparative analysis of the early activation marker CD69 on peripheral blood mononuclear cells (PBMC) of patients with AE and healthy controls after in vitro culture with crude E. multilocularis antigen revealed that specific expression of CD69 was induced in CD4(+)T lymphocytes as well as in CD8(+)T lymphocytes. Using a protocol for intracellular staining of cytokines followed by fluorescence activating cell sorting (FACS) analysis, production of interleukin (IL)-2, IL-5 and IL-10 was detected in CD4(+)as well as in CD8(+)lymphocytes. Most notably, there was a definite increase in the expression of IL-10 in CD8(+) lymphocytes from patients with alveolar echinococcosis. The data support an important role of CD8(+) lymphocytes in the long persistence of the metacestode.