Deficient Transendothelial Migration of Leukocytes in Q Fever: The Role Played by Interleukin-10.

Chronic Q fever is characterized by deficient cell-mediated immune response, lack of granulomas, and dysregulation of the cytokine network. Altered transendothelial migration(TM) of peripheral-blood mononuclear cells might account for impaired immune response. TM of lymphocytes and monocytes was decreased in patients with Q fever endocarditis, compared with that in patients recovering from acute Q fever and in control subjects. This defect is related to interleukin (IL)—10, a cytokine involved in the chronic evolution of the disease; neutralizing anti—IL-10 antibodies corrected TM of mononuclear cells from patients with Q fever endocarditis. IL-10 may account for deficient protective immunity in patients with Q fever endocarditis by impairing TM. [ABSTRACT FROM AUTHOR]