Antibody against p58 surface antigen of RA-2 rat rhabdomyosarcoma cells inhibits their metastatic activity.
Antibodies generated against the whole membrane preparation isolated from rhabdomyosarcoma RA-2 cells were shown by immunoblotting and immunoaffinity chromatography to recognize 58-kDa polypeptide, p58. The latter was confirmed to be a surface molecule in a test of radioiodination of RA-2 membrane by lodogen. The antibodies added to a suspension of RA-2 cells before their inoculation into rats decreased metastatic activity 50-fold without any noticeable influence on RA-2 proliferation level and viability. The data indicate that masking of p58 surface antigen by antibodies could make RA-2 cells unable to form experimental metastases in lung. We suggest that p58 may participate in the specific recognition by RA-2 of lung endothelial cells.