Immunologic insights into uveitis and retinitis: the immunoregulatory circuit

The immune response is a complex series of cellular interactions, which is controlled by several regulatory mechanisms to insure an appropriate response. One of the most important mechanisms of control is the suppressor T cell immunoregulatory circuit. The immune response is presented in detail and examined from three different perspectives: 1) a clinical disease in which it is markedly abnormal--namely, the acquired immune deficiency syndrome or AIDS, 2) a clinical disease in which no systemic abnormality is apparent but where a local derangement in immunoregulation may be important--namely, idiopathic uveitis, and 3) a situation in which it is purposefully altered by medications for therapeutic purposes. Three drugs currently used in the treatment of uveitis--prednisone, cyclophosphamide, and cyclosporine--will be examined and compared.