Interaction between a synthetic polypeptide, TIGAL, and Fc receptors on non-bursa-derived chicken lymphoid cells

Autoradiographic studies have shown that radioiodinated TIGAL binds in vitro to a small but varying fraction of lymphoid cells from bursectomized, agammaglobulinemic chickens, whereas no binding of radioiodinated TGAL or a variety of other radioiodinated antigens can be observed. The binding of [125I]TIGAL is inhibited by antigen-antibody complexes. Radioiodinated antigen-antibody complexes are bound to a similar proportion of the lymphoid cells from bursectomized chickens, and this binding is inhibited by preincubation of the cells with unlabeled TIGAL but not with TGAL. These results indicate a cross-reaction at the level of Fc receptors between determinants on TIGAL and on IgG.