The effect of anti-immunoglobulin antibodies of Fc rosettes.

This study demonstrated that Fc rosettes detected by antibody-labeled bovine erythrocytes can be inhibited by immune complexes of rabbit IgG (b4 allotype) and anti-b4 IgG, thus showing that these complexes effectively compete for the receptor for erythrocyte-antibody rosettes. Incubation of mouse lymphocytes with goat F(ab')2 anti-mouse IgG did not inhibit Fc rosettes. When immunoglobulin on murine and human B lymphocytes was redistributed in a polar cap on the membrane by interaction with anti-immunoglobulin antibodies, the number of Fc rosettes after 'capping' was unchanged; most of the indicator erythrocytes, however, were distributed in a cap as well. This erythrocyte cap was superimposed on the immunoglobulin cap.