How does the body achieve the functional silencing of antigen reactive clones?

a reasonable if fairly narrow essay (narrow in subject that is) can't remember How does the body achieve the functional silencing of antigen reactive clones? The central tenet of the immune system is the ability to recognise and remove non-self components without affecting self components. The T cells and B cells of the immune system express a vast repertoire of antigen receptors. It is thought that the germline TCR repertoire is composed of in the …

…lation of IgM in the anti-MHC specific B cells prevented their homing to the peripheral lymphoid organs, accounting for their absence. In the case of the anti-HEL B cells, they express IgD which could mediate this homing process. However despite IgD ligation being sufficient for activation, these cells are unresponsive and so a mechanism of tachyphylaxis whereby there are changes in the signal transduction across the membrane may be playing a part.- bit tenuous.