Natural product derived immune-regulatory agents.

We can now declare that the clinical goal of immune intervention as a therapeutic strategy for neoplastic, infectious, autoimmune and inflammatory diseases, has been achieved and in many instances obtained regulatory approval. Although, interest in and optimism for this approach has fluctuated, in the last 20years, immunotherapy has progressed from trials with crude microbial mixtures and extracts to the sophisticated use of pure cultured bacterial, synthetized active moieties identified from crude extracts, analogues therefrom and agonists and antagonists identified during screening resulting in reproducible pharmacologically active compounds with multiple mechanisms of action. Our current understanding of the mechanism of action for immunoregulatory agents contributes to the future discovery of improved strategies to use these and future immunotherapies. In this review we have identified and discussed, those drugs that have been approved and or are in clinical development as immunoregulatory agents, emphasizing those derived from or associated with natural product.