Reactivity of serum from rous-sarcoma-bearing chickens with autochthonous and with allogeneic tumor cells: preferential autochthonous recognition.

Complement-medicated cytotoxicity and indirect immunofluorescence assays showed that sera from random-bred chickens bearing Rous sarcoma (RS) tumors are usually more reactive in vitro against RS cells of autochthonous than of allogeneic origin. Absorption of such sera with autochthonous, but not with allogeneic, RS cells abrogated the fluorescence staining capacity. Sera from tumor-bearing birds did not stain normal chicken embryo cells (CEC), but reacted with a higher proportion of CEC transformed by the RS virus than with cultured PS tumor cells. Tumor cells incubated at 37 degrees C with autochthonous serum and fluorescent horse anti-chicken immunoglobulin conjugate displayed cell surface fluorescence patching.