The autologous mixed lymphocyte response: delayed T cell tolerance to B cells in XID mice

The autologous mixed lymphocyte response (AMLR) is characterized by the proliferation of neonatal, but not adult, thymic T cells when cocultured with adult syngeneic B cells. Studies of the AMLR have revealed a temporal correlation between loss of T cell self-reactivity and development of stimulatory B cells. Such observations impart a role for B cells in the development of T cell tolerance. To test this hypothesis, we studied the AMLR in X-chromosome-linked immune-defective (XID) mice. As B cell maturation is delayed in this strain, we postulated that the AMLR-stimulatory capacity of B cells from XID mice might be impaired and lead to delayed acquisition of T cell tolerance. This report provides evidence that T cell tolerance to self-B cells is delayed in XID mice. Normal mice possess tolerant thymic T cells by 1 week of age, whereas thymic T cells in the XID mouse remain self-reactive through 4 weeks of age. These results reinforce a role for B cells in the development of T cell tolerance to self.