Strain specific analysis of MUC1 gene expression in wild-type C57BL/6 mice and hMUC1 mice by RT-PCR. Mouse Muc1 mRNA was detectable only in splenocytes of wild-type C57BL/6 mice (+/+). Human MUC1 mRNA was detectable only in homozygous B-hMUC1 mice (H/H), but not in wild-type mice. 

Western blot analysis of MUC1 protein expression in homozygous B-hMUC1 mice. Various tissue lysates were collected from wild-type C57BL/6 mice (+/+) and homozygous B-hMUC1 mice(H/H), and then analyzed by western blot with anti-MUC1 antibody. 40 μg total proteins were loaded for western blotting analysis. Human and mouse MUC1 was detected in wild-type mice and homozygous B-hMUC1 mice due to the cross-reactivity of antibodies.

Subcutaneous homograft tumor growth of B-hMUC1 MC38 cells. B-hMUC1 MC38 cells (5x10⁵) and wild-type MC38 cells (5x10⁵) were subcutaneously implanted into wild-type C57BL/6 mice (female, 8-week-old, n=6). Tumor volume and body weight were measured twice a week. (A) Average tumor volume ± SEM. (B)  Body weight (Mean± SEM). Volume was expressed in mm³ using the formula: V=0.5 X long diameter X short diameter². As shown in panel A, B-hMUC1 MC38 cells were unable to establish tumors in wild-type C57BL/6 mice.

Subcutaneous homograft tumor growth of B-hMUC1 MC38 cells. B-hMUC1 MC38 cells(2-C07 clone) (5x10⁵) and wild-type MC38 cells (5x10⁵) were subcutaneously implanted into B-hMUC1 mice (female, 8-week-old, n=6). Tumor volume and body weight were measured twice a week. (A) Average tumor volume ± SEM. (B)  Body weight (Mean± SEM). Volume was expressed in mm³ using the formula: V=0.5 X long diameter X short diameter². As shown in panel A, B-hMUC1 MC38 cells were able to establish tumors in vivo and can be used for efficacy studies.