Lymphocyte requirement for the functional development of follicle-associated epithelium

Follicular development in the bursa of Fabricius was disrupted by testosterone treatment and chorioallantoic membrane grafting. Analysis by a quantitative histological technique demonstrated that testosterone treatment causes a dose dependent delay in development by inhibiting lymphoid proliferation. Inhibition of lymphoid development prevented the development of carbon transport ability by follicle associated epithelium. Reconstitution of follicular development by grafting treated bursae to the chorioallantoic membrane of untreated hosts results in the development of functional follicle associated epithelium. These results establish the lymphoid requirement for the development of transport ability by the follicle-associated epithelium.