Thymus grafts induce B cell development in nude, X-linked immune deficient mice

Mice simultaneously expressing the mutations nude and X-linked immune deficiency (xid) were previously shown to have pro-B cells and/or early pre-B cells while lacking C mu+ and surface Ig+ cells. We now report that thymus grafts restore both T cells and B cells in nude-xid mice. By the use of Thy-1 and Igh allogeneic donors it was shown that both the T and B cells were host derived. The B cells had a functional phenotype typical of xid mice. It is concluded that the maturation of xid B cells past the pro-B or early pre-B stage is T cell dependent.