Fc receptor-bearing lymphoid cells in the chicken. I. Characterization of the Fc(IgG) receptor.

The receptor for FC(IgG) on chicken lymphoid cells was investigated by EA rosette techniques using sheep erythrocytes sensitized with a sub-agglutinating dose of anti-sheep erythrocyte (SRBC) chicken serum. Chicken lymphocytes did not form rosettes with SRBC coated with rabbit antibody, and human and mouse lymphocytes did not bind SRBC sensitized with chicken antibody. Only avian sera were effective in blocking the Fc receptor. Similarities between chicken and mammalian Fc receptors were demonstrated as both are pronase sensitive, trypsin resistant, and are distinct from surface immunoglobulin. Fc receptors were also distinguished from avian bursa- and thymus-specific antigens. Additional Fc receptor-bearing cells were revealed in bursa, spleen and bone marrow lymphocytes after neuraminidase treatment.