Cell lines derived from C57BL/6 mice are tumorigenic in SCID mice. Individual MOVCAR cell lines isolated from C57BL/6 mice (MOVCAR 12, 5612, 5447 and 5438) were tested for tumorigenicity in SCID mice by i.p. injection of 0.5 - 1.0 × 107 cells. H&E stained sections show the presence of tumor cells in the ovary (a-d) and peritoneum (i-l). The tumors derived from all cell lines were poorly differentiated carcinomas. The neoplastic cells were usually arranged in solid sheets and occasionally formed glandular structures and/or irregular slit-like spaces. On the peritoneal surface, these cells also formed papillary structures. Immunohistochemical detection of TAg (e-h and m-p) shows positively staining tumor cells with no staining of surrounding normal tissue. All micrographs were taken at the same magnification and the calibration bar shown in panel p corresponds to 100 μm.