OBJECTIVETo study the relationship between the change of regulatory T cell number in CD4+ T subset and the growth of tumor in H22 hepatocellular carcinoma-bearing mice.

METHODSTumor-bearing mice were established by subcutaneous inoculation of H22 hepatocelluler carcinoma cells. Flow cytometry was used to detect the expression of CD4 and CD25 molecules of the T cells which came from the tumor-bearing mice. The Foxp3 gene expression was detected by RT-PCR and flow cytometry. CD4+ CD25+ T cells and CD4+ CD25- T cells were separated and purified by immuno-magnetic beads. The proliferation and suppressive function of the CD4+ CD25+ T cells coming from tumor-bearing mice was measured by [3H]-thymidines incorporation experiment in vitro, and then effect of CD4+ CD25+ T cells originated from hepatocellular carcinoma-bearing mice on tumor growth was observed in vivo.

RESULTS(1) Compared with mice of the control group, the percentage of CD4+ CD25+ T cells of CD4+ T cells in tumor-bearing mice is not only higher in draining lymph nodes (18.80% < or = 0.06%) vs. (9.50% +/- 0.03%), (P < 0.01), but also higher in non-draining lymph nodes (LN) and spleen (SP), LN: (16.28% +/- 0.02%) vs. (9.50% +/- 0.03%), P < 0.01; SP: (17.28% +/- 0.06%) vs. (11.08% +/- 0.04%), (P < 0.05). The expression of regulatory T cell specific marker Foxp3 gene was also increased. In the same tumor-bearing mice, the number of CD4+ CD25+ T cells in draining lymph node was relatively higher than the contralateral nondraining lymph node, but the difference was statistically not significant (18.8% +/- 0.06%) vs. (16.28% +/- 0.02%), (P > 0.05). (2) The CD4+ CD25+ T cells purified from tumor-bearing mice--like naturally occurring regulatory T cells--were anergic to anti-CD3 monoclonal antibody stimulation in vitro, but it could suppress CD4+ CD25- T cells proliferation. (3) The percentage of CD4+ CD25+ T cells was positively related to tumor size. It could also suppress the anti-tumor effect of CD4+ CD25- T cells in vivo. Conclusion The growth of hepatocellular carcinoma in mice can boost the amount of regulatory T cells. The amount of regulatory T cells is positively related to tumor size, indicating that attack on regulatory T cells could be used as one of modalities in cancer treatment in the future.

Animals ; CD4 Antigens ; immunology ; CD4-Positive T-Lymphocytes ; cytology ; immunology ; metabolism ; Cell Line, Tumor ; Cell Proliferation ; Female ; Flow Cytometry ; Forkhead Transcription Factors ; genetics ; metabolism ; Gene Expression Regulation, Neoplastic ; Interleukin-2 Receptor alpha Subunit ; immunology ; Liver Neoplasms ; immunology ; metabolism ; pathology ; Liver Neoplasms, Experimental ; immunology ; metabolism ; pathology ; Lymph Nodes ; immunology ; metabolism ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Neoplasm Transplantation ; Reverse Transcriptase Polymerase Chain Reaction ; Spleen ; immunology ; metabolism ; T-Lymphocytes, Regulatory ; cytology ; immunology ; metabolism

Objective:To observe the effects of modified Liuwei Dihuangtang on serum fibroblast growth factor 23 （FGF23）， full-length intact parathyroid hormone （iPTH）， and 1，25-dihydroxyvitamin D₃ ［1，25（OH）₂D₃］ levels and Klotho and FGF23 protein expression in renal and bone tissues of rats exposed to high phosphorus combined with adenine， so as to explore the mechanism of modified Liuwei Dihuangtang against renal osteopathy. Method:One hundred and thirty healthy adult SD rats were randomly divided into five groups， namely normal group（n=10），high phosphorus group（n=30），model group（n=30），modified Liuwei Dihuangtang group（n=30） ， and calcitriol group（n=30），and rats in each group were further classified based on three time points， namely 8，10， and 12 weeks. Rats in the normal group were fed with normal diet， the ones in the high phosphorus group with high phosphorus diet， and those in the other groups with adenine and high phosphorus diet for inducing renal osteopathy. Rats in the normal group，high phosphorus group， and model group were intragastrically administered with distilled water （10 mL·kg^-1·d^-1），the ones in the modified Liuwei Dihuangtang group with modified Liuwei Dihuangtang （2.556 g·kg^-1·d^-1） ， and those in the calcitriol group with calcitriol （0.09 μg·kg^-1·d^-1）. Result:Compared with the normal group and high phosphorus group at the weeks of 8，10 and 12，the model group displayed significantly elevated blood urea nitrogen（BUN），serum creatinine（SCr），serum phosphorus，iPTH，FGF23，renal interstitial fibrosis score， and FGF23 expression in renal and bone tissues， but lowered serum calcium and 1，25（OH）₂D₃ and Klotho protein expression in renal and bone tissues（P<0.05 ，P<0.01）. Compared with the model group at the weeks of 8，10 and 12， the modified Liuwei Dihuangtang and calcitriol both significantly decreased the serum BUN，SCr，serum phosphorus，iPTH， FGF23， tubulointerstitial semi-quantitative score， and FGF23 expression in renal and bone tissues， while increased the serum calcium，1，25（OH）₂D₃， and Klotho protein expression in renal and bone tissues （P<0.05，P<0.01）. There was no significant difference in the above-mentioned indexes between the modified Liuwei Dihuangtang group and the calcitriol group at the same time point. Conclusion:Klotho-FGF23 axis is probably involved in renal osteopathy. The modified Liuwei Dihuangtang effectively improves renal function，alleviates pathological changes in renal and bone tissues，and regulates calcium and phosphorus metabolism to protect the bone， which is related to its regulation of Klotho-FGF23 axis.