Significant elevated number of CD3 + CD25+ T cells in peripheral blood was detected 21 weeks following tumor induction, when animals were given 3 times of drug administration in SL3261R group (P < 0.05 compared with all groups), suggesting the recombinant bacteria-based 4-1BBL vaccines can enhance the immune function of tumor-bearing mice. Here, IL2RA is linked to neoplasm.