Mouse monoclonal antibodies with restricted specificity for human renal cell carcinoma and ability to modulate the tumor cell growth in vitro.

Three mouse monoclonal antibodies (MAbs), KRC-1, -2 and -3(IgG1) were produced against cultured cells of human renal cell carcinoma (RCC) cell lines. All of them had restricted specificity for subset of RCC, but did not react with other tumor cell lines, tumor and normal tissues including kidney. The effect of these MAbs on the tumor cell growth in vitro was examined both in soft agar and in plate culture systems. All of them showed modulator effect on the tumor cell growth: KRC-1 showed stimulation effect and others, KRC-2 and -3, suppression one in the both systems. The specificity was observed in the modulator effects. KRC-1 detected a 135 kd glycoprotein in immunoblotting. KRC-2 detected a high molecular weight antigen (ca. 1200 kd) in gel filtration. All the antigens showed affinity for Con A lectin. Molecular properties of the antigens appeared to be different from those of previously reported RCC-associated antigens. The three MAbs seem to be useful to study mechanism of growth regulation in transformed cells.