Immunoblotting of monoclonal anti-cytoskeletal antibodies with cytoskeletal extracts of HeLa and MCF-7 cells.

Cytoskeletal extracts of HeLa and MCF-7 cells were separated by SDS polyacrylamide gel electrophoresis, electrotransferred to nitrocellulose paper and exposed to five of our monoclonal antibodies (mabs) against structures of the cytoplasm as demonstrated in indirect immunofluorescence. Three of them reacted with cytokeratins according to histological evidence. All mabs tested in this study were reactive in immunoblotting. The broad-range anti-cytokeratin antibody A45-B/B3 was shown to react with cytokeratin polypeptides 8 and 18 and possibly 7, but not with cytokeratin 17.A53-B/A2 bound only to cytokeratin 19.Mab A 51-B/H4 showed a reaction with cytokeratin 18. Two mabs not yet described in detail (A45-C/H1 and A45-C/H9) reacted with a single band of 25 kD and may detect a cytoskeleton-associated protein.