ANTIBODIES TO INTERMEDIATE FILAMENTS AS DIAGNOSTIC-TOOLS - HUMAN GASTROINTESTINAL CARCINOMAS EXPRESS PREKERATIN

Abstract

Primary gastrointestinal carcinomas (25) were studied using immunofluorescence microscopy with affinity-purified antibodies to prekeratin and to vimentin. The tissues were alcohol fixed and paraffin embedded before use. In all cases (i.e., 1 case of esophagal carcinoma, 7 stomach carcinomas and 17 large bowel carcinomas) the tumor cells were stained by antibodies to prekeratin. In cases in which only very few tumor cells were present, such as signet ring carcinoma, immunofluorescence with prekeratin antibody provided an easy way to visualize single tumor cells. When the same specimens were tested with antibodies to vimentin, the tumor cells were unstained, and only the fibroblasts and vessels of the stroma were decorated. Four tumors were negative when tested with antibodies specific for desmin, glial fibrillary acidic protein or neurofilaments. Three metastases to the abdominal region from tumors originating in the ovary, stomach and large bowel were like the primary tumors in that the tumor cells were positive when stained with antibodies to prekeratin and negative when tested with the antibodies to vimentin.