ABSTRACT
Tolerance is best-defined as a state of antigen-specific immunological unresponsiveness. This definition has two important corollaries:
1. When tolerance is experimentally induced, it does not affect the immune response to antigens other than the one used to induce tolerance. This is a very important feature that differentiates tolerance from generalized immunosuppression, in which there is a depression of the immune response to a wide array of different antigens. Tolerance may be transient or permanent, whereas immunosuppression is usually transient.
