Transgenics and the Study of Tolerance

The complex mechanism by which an organism becomes immunologically self-tolerant and yet remains responsive to foreign antigens is not well understood. Transgenic technology, which makes possible the controlled expression of select genes in the developing mammal, provides us with a versatile tool for the study of tolerance in vivo. The permanent integration of selected genes into the mouse germline has allowed the expression of self-reactive T- and B-cell receptors, the ectopic expression of self-antigens, and the expression of modified self-antigens. In this review, we discuss methods for the production of transgenic mice and highlight experiments that have used transgenic animals to study tolerance.