The role of regulatory T lymphocytes in asthma pathogenesis.

Several subtypes of regulatory or suppressive T cells have been described that can prevent activation of effector T cells in vitro and in vivo in animal models. Recent evidence suggests a deficit in suppressive activity of both CD4(+)CD25(+) regulatory T cells, and interleukin (IL)-10 producing regulatory T cells may play a role in development of allergic sensitization. If therapies can be devised to redress the balance between regulatory and effector T cells, there may be hope for the control and prevention of asthma.