The mabs react with plakophilin 2, a member of the arm-repeat family of proteins which can occur in at least 2 splice forms (2a and 2b). Plakophilin 2 assembles with other proteins to form the desmosomal plaque in simple and glandular epithelia, the basal layer of certain stratified epithelia, all layers of some stratified epithelia, and in nonepithelial desmosome-possessing tissues such as myocardium, Purkinje fibers, and dendritic reticulum of lymph node follicles. In all these cells, including a variety of cell types devoid of desmosomes, plakophilin 2 is highly enriched in the karyoplasm. Polypeptide reacting: Plakophilin 2, Mr 100 kD (SDS-PAGE); MW calculated from aa sequence: 92,750 (pI 9.33) and 97,410 (pI 9.38)
Tumors specifically detected: Positive staining was obtained with several carcinomas derived from simple-type epithelia (e.g. hepatomas, colon carcinomas) and some adenocarcinomas derived from stratified epithelia (oesophagus carcinoma). The antibody was negative with all leiomyosarcomas tested.