Autologous transplanted colonic carcinoma in Sprague-Dawley rats

Thirty-five adult male Sprague-Dawley rats received weekly subcutaneous injections of 1,2-dimethylhydrazine (DMH) for 12 weeks. At the end of this period, 31 rats had developed colonic carcinomas (CC). A fragment (1 mm3) of each CC was autotransplanted into the subcapsular space of the left kidney of the respective rats. After an additional 3 weeks, the rats were sacrificed. The left kidney in 20 of the 31 rats (65%) demonstrated tumors at the site of transplantation. The transplanted tumors demonstrated markers of viability such as a PCNA positive cells, mitotic figures, mucin secretion, neo-vascularization, invasion of the adjacent kidney tissue and infiltration of mononuclear cells. The frequency of tumor cells exhibiting the tumor associated antigens CO17-1A, GA73-3, BR55-2, GICA 19-9 was similar or higher in most of the autotransplants when compared to the donor tumor. Since MAb17-1A is being used in immunotherapy of metastatic CC in humans, the present model may offer a feasible method to assess various biotherapeutic approaches of metastatic CC based on the use of MAb17-17A.