B-cell and T-cell function in systemic lupus erythematosus.

The process of autoantibody production in systemic lupus erythematosus is characterized by findings of both an antigen-driven response and polyclonal B-cell activation. Autoantibody production does not appear to be critically dependent on the presence of the CD5+ B cell subset. Increasing evidence supports a role for T helper cell type 2 cytokines, such as interleukin-4 and interleukin-6, in promoting and perpetuating B-cell hyperactivity and autoantibody formation.