Phenotypic characterization of peripheral T cells and their dynamics in scrub typhus patients.

Phenotypic characterization of peripheral T cells and their dynamics in scrub typhus patients.

Blog Article

BackgroundScrub typhus, caused by Orientia tsutsugamushi infection, is one of the main causes of febrile illness in the Asia-Pacific region.Although cell-mediated immunity plays an important role in protection, little is known about the phenotypic changes and dynamics of leukocytes in scrub typhus patients.Methodology/principal findingsTo reveal the underlying mechanisms of immunological pathogenesis, we extensively analyzed peripheral blood leukocytes, especially T cells, during acute and convalescent phases of infection in human patients and compared with healthy volunteers.

We observed neutrophilia and CD4(+) T lymphopenia in the acute phase of infection, followed by marigold velvet curtains proliferation of CD8(+) T cells what is faux shagreen made of during the convalescent phase.Massive T cell apoptosis was detected in the acute phase and preferential increase of CD8(+) T cells with activated phenotypes was observed in both acute and convalescent phases, which might be associated or correlated with elevated serum IL-7 and IL-15.Interestingly, peripheral Treg cells were significantly down-regulated throughout the disease course.

Conclusions/significanceThe remarkable decrease of CD4(+) T cells, including Treg cells, during the acute phase of infection may contribute to the loss of immunological memory that are often observed in vaccine studies and recurrent human infection.