Effect of nano-sized-Fe3O4-lipoteichoic acid from Bifidobacterium on cytokine expression in human gastric cancer in nude mice / 中华微生物学和免疫学杂志

ABSTRACT

Objective To investigate the effect of lipoteichoic acid from Bifidobacterium loaded with magnetic particle nano-sized-Fe3O4(nano-sized-Fe3O4-BLTA)on several cytokines in vivo expression in beterologous graft model for human gastric cancer in nude mice.and to analyze the inhibition mechanism of nano-sized-Fe3 O4-BLTA on BGC-823 human gastric carcinoma transplanted tumor.Methods Forty male nude mice(BALB/e.nu/nu)were used for in vivo transplant tumor model.the experimental animals were randomly divided into five groups to administrated by several dosages of Hano-sized-Fe3 O4-BLTA,and were executed after 12 d.The tumors were collected and photographed.and the tumor tissues were used for differ-ent assays for measuring tumor inhibition.The peritoneal fluid was extracted to isolate the macrophages for cytokines assays.Using irmnunohistochemical staining for vascular endothelial growth factor(VEGF)and CD3 l in tumor to investigate the tumor inhibition rate.Double antibody sandwich ELISA was used to detect the level of cytokine change.Results The mice treated with low dosage(10 μg/d)of nano-sized-Fe3O4-BLTA.the growth inhibifion rate of tumor was 49%,and the levels of VEGF(0.0224±0.0763)and CD31 (57.000 4±6.790)were lower than other treated groups(P<0.01).The high dosage(100μg/d)and me-dium dosage(50μg/d)of nano-sized-Fe3 O4-BLTA groups were significant difference(P<0.01)on the content of cytokines excreted by macrophages.The level of TNF-α(39.4040 ±-1.5590)induced by the low dosage group was higher relatively(P<0.01).Conclusion Nano-sized-Fe3O4-BLTA exerts an inhibiting effect on the growth of human gastric cancer in nude mice.Using nano-sited-Fe3 O4-BLTA,LTA can get more permeability and improve the therapy effect.which will be a new drug on the stomach cancer targeted therapy.