The new immunology.

Among the biomedical sciences, immunology stands out as a discipline in which knowledge emanating from fundamental research has rapidly been transferred to the clinical paradigm, with consequent improvement in human health. Virtually all medical subspecialties have benefitted from diagnostic reagents and technologies provided by basic immunology. In terms of numbers of lives saved, immunologic-based therapeutic strategies, most notably vaccination, rank among the most effective measures ever achieved by medical intervention. Yet, despite immunology's profound impact on medicine and the longstanding recognition of many of the general principles and cellular components involved in immunity, until relatively recently, the operational workings of the immune system eluded precise definition. The abstract nature of the immune system rendered the field intangible or, at the very least, confusing, to the nonimmunologic medical community. However, in recent years, this situation has changed radically, as cell cloning, hybridoma, and recombinant DNA technologies have provided the means to delineate the precise immunologic cellular structures and interactions. The purpose of this review is to highlight a few of the most significant advances in immunology during the past decade, and to show how they have made possible the translation of abstract concepts of classical immunology into tangible, structural information. Striking gains in the understanding of antigen recognition, one of the most fundamental aspects of immunity, are described as an illustrative case.