Immunohistochemical detection of cytokeratins in the irradiated rat mandibular gland

UNLABELLED: BACKGROUND/MATERIAL AND METHODS: The present study is a prerequisite for the exploration of the cytokeratin (CK) profile in rat salivary gland tumors. In 59 rat mandibular glands we investigated the distribution of CK by immunohistochemical analysis. The animals differed in age and pretreatment status (irradiation versus no irradiation).

RESULTS: The monoclonal antibodies (CKE3, Ks13.1, NCL5D3, K8.12; against CK 17, CK 13, CK 8 and CK 13/15/16, respectively) identified different epithelial structures in rat salivary gland tissue, including intercalated duct cells (ICD), striated duct cells (SD), granular convoluted tubules (GTC), excretory duct cells (ECD) and myoepithelial cells (MC). As typical results, CKE3 usually stained the ICD, SD and ECD moderately to strongly and stained the GTC slightly. K8.12 staining was restricted to ECD and MC. Differences in immunoreactivity were seen between irradiated and non-irradiated glands, predominantly with stronger staining in the irradiated group.

CONCLUSIONS: Previous radiation has to be considered when interpreting immunohistochemical stainings of salivary gland tissue, especially in tumor differentiation studies following irradiation.