Failure to detect soluble tumor associated antigen by radioimmunoassay in bovine lymphoma

The detection of circulating soluble tumor-associated antigen by radioimmunoassay was attempted in cows with lymphoma. The assay system did detect PAGE-purified tumor-associated antigen but did not detect immunoreactive substances in the sera of 20 affected animals and 20 normal cattle. Similarly, ultrafiltration of low pH-dissociated serum to separate immune complexes did not aid in the detection of antigen.