OBJECTIVETo construct human-SCID chimeric mice through implantation of mononuclear cells from human cord blood and study the immunoreaction of SCID-Hu IC mice immunized with rAd5HPV16L1-E7 vaccine.

METHODS(1) Experiment groups were injected with the suspension of mononuclear cells from human cord blood through a tail vein; the control ones were injected with non serum RPMI 1640 medium. Eight weeks after implantation, blood was collected and human serum IgG level in the mice were tested, and human CD45, CD3 and CD19 were determined. (2) SCID-Hu IC mice were divided into two groups: in group A the mice were immunized intraperitoneally with rAd5HPV16L1-E7 virus and in group B the mice were immunized through nasal drip with rAd5HPV16L1-E7 virus. At the end of fourth week, the serum specific IgG antibody to rAd5HPV16L1-E7 virus, IFN-gamma in culture medium of spleen lymphocyte and T-lymphocyte propagation were tested.

RESULTS(1) In the experiment groups, the number of mice positive for human IgG was 10/15, the average values of CD45, CD3 and CD19 were (9.39+/-4.21), (3.25+/-3.99) and (1.69+/-0.75), respectively. In the control ones, the human IgG, CD45, CD3 and CD19 were negative. (2) The results in the experiment groups showed that the IFN-gamma and T-lymphocyte stimulated by HPV16 protein were higher than those in the non-stimulated group (P less than 0.05).

CONCLUSION(1) The results indicated that the construction of human-SCID chimaera through the implantation of mononuclear cells from human cord blood into SCID mice was successful. They also indicated that the reconstructed SCID-Hu IC mice has the ability to produce immune response against rAd5HPV16L1-E7 recombinant virus.