Abstract:

Objective   To investigate the effect of allogeneic anti-CD3 monoclonal antibody activated killer (CD3AK) cells on human renal carcinoma xenografts in severe combined immunodeficiency (SCID) mice. Methods  Xenograft models were established by injecting human renal cancer cells into the left lower limb of SCID mice, and then CD3AK cells were injected into the tail vein to observe the biological characteristics of the mice. The 32 healthy male SCID mice were randomly divided into 4 groups (n=8 each): allogeneic CD3AK cells were injected intravenously before tumor-bearing (group A); PBS was injected intravenously before tumor-bearing (group B); allogeneic CD3AK cells were injected intravenously after tumor-bearing (group C); PBS was injected intravenously after tumor-bearing (group D). The CD3+ expression was detected with immunohistochemical method; the body weight of mice and tumor volume were measured; the spleen index (spleen weight / body weight) was calculated to observe the inhibition of allogeneic CD3AK cells on renal carcinoma growth and on the immune function of mice. Results  Compared with the control group ( B and D ), the average spleen index was significantly increased, while the tumor weight was markedly reduced and the tumor growth was slow in group A and C group (P<0.05). There was no statistical difference of average spleen index between group A and group C (P>0.05). Compared with group C, the tumor weight was remarkably reduced and the tumor growth was retarded in group A (P<0.05). Immunohistochemistry showed that CD3+ cells were positively expressed in tumor tissues in group C, but not expressed in other groups. Conclusion  Allogeneic CD3AK cells can remarkably inhibit the growth of renal carcinoma xenografts in SCID mice, as well as enhancing the immune function of mice to play its antitumor effect.

Key words: Allogeneic anti-CD3 monoclonal antibody activated killer (CD3AK) cells, SCID mice, Renal neoplasm, Tumor xenografts