ABSTRACT
BACKGROUND:CTLA-4Ig as a tolerance-induction agent is a potential strategy in graft-versus-host disease prevention. OBJECTIVE:To investigate the efficacy of CTLA4Ig-gene-modified bone marrow stromal cels mediated by adenovirus to induce T-cel tolerance of haploidentical donors. METHODS: The bone marrow stromal cels isolated culture from the bone marrow of HLA haploidentical donors were transfected by recombinant adenovirus encoding CTLA4IgcDNA (AdCTLA4Ig) at a multiplicity of infection=50 for 72 hours. The expression rate and the location of CTLA4Ig in the transfected cels were detected by fluorescence microscope after immunofluorescence staining. CTLA4Ig-modified bone marrow stromal cels (2×104, 4×104and 8×104) were respectively co-cultured with 105 T cels from the peripheral blood of HLA haploidentical donors and 105 peripheral blood mononuclear cels from recipients. The proliferative inhibition rate was determined by MTT assay, and the level of interleukin-2 in the supernatant was detected by ELISA. The bone marrow mononuclear cels (1×105/wel) were co-cultured with CTLA4Ig-modified bone marrow stromal cel layers constructed in 6-wel plates. The number of bone marrow mononuclear cels and colony-forming unit-granulocyte macrophages were calculated after 5-day culture. RESULTS AND CONCLUSION: The expression rate of CTLA4Ig at the multiplicity of infection=50 was as high as 85%, and the immunofluorescence signals of CTLA4Ig were distributed unevenly in the cytoplasm. The inhibition rates of 2×104, 4×104, and 8×104 CTLA4Ig-modified bone marrow stromal cels on proliferation of T cels were higher than that of untransfected cels. The levels of interluekin-2 in the corresponding cel groups were significantly lower than that in the untransfected cels (P 0.05). These findings indicate that CTLA4Ig-modified bone marrow stromal cels mediated by adenovirus can induce immune tolerance of T-lymphocyte from HLA haploidentical donors in vitro.
ABSTRACT
BACKGROUND:Imatinib resistance is a key issue in treatment of chronic myeloid leukemia. It is confirmed that the leukemia cels can obtain drug resistance phenotype mediated by adhesion to the bone marrow stromal cels (BMSCs). But, the role of BMSCs in imatinib resistance is unclear because chronic myeloid leukemia is deficient in adhesion function. OBJECTIVE: To in vitro simulate the bone marrow microenvironment of patients with chronic myeloid leukemia and to explore its influences on imatinib sensitivity as wel as possible mechanisms. METHODS:BMSCs isolated from patients with chronic myeloid leukemia but not undergoing treatment were co-cultured with K562 cels to construct the BMSCs-K562 cel co-culture model in chronic myeloid leukemia patients, then exposed to 0.2-3.2 μmol/L imatinib for 48 hours, and the proliferation inhibition rate of K562 cels was studied by MTT assay. The apoptosis rate of K562 cels and the expression of the CXCR4 in K562 cels exposed to 0.5 μmol/L imatinib for 72 hours were detected by flow cytometry. The K562 cels were exposed to 0.5 μmol/L imatinib for 4 hours and labeled by Calcein-AM fluorescent labeling sytem, and then, the adhesion rate of the K562 cels was calculated based on fluorescence intensity. RESULTS AND CONCLUSION: The suppressing effect of imatinib (0.2-3.2μmol/L) on the proliferation of K562 cels was weakened significantly by co-culture with the bone marrow stromal cels from patients with chronic myeloid leukemia. The apoptosis rate of K562 cels exposed to 0.5 μmol/L imatinib for 72 hours in co-culture group was significantly lower than that in the suspension culture group (P=0.020). The positive rates of CXCR4 in the co-culture group and suspension culture groups were both increased after exposure to 0.5 μmol/L imatinib for 72 hours (P=0.001). The adhesion rate of the K562 cels to the BMSCs was elevated from (32.18±6.17)% to (68.97±11.08)% when the K562 cels were exposed to 0.5 μmol/L imatinib for 4 hours, and the difference had statistical significance (P=0.022). These findings indicate that the co-culture with the BMSCs from patients with chronic myeloid leukemia can mediate K562 cels resistance to imatinib, which may be related to that the co-culture with BMSCs and exposure to imatinib can induce the K562 cels to express CXCR4. But the mechanism needs in-depth studies.
ABSTRACT
Objective To discuss the incidence trends of hyperuricemia in people of different TCM constitutional types by analyzing the constitutional types of patients with hyperuricemia,and to lay a foundation for follow-up study in preventive and therapeutic measures for hyperuricemia.Methods 518 healthy people and 525 people of hyperuricemia were included in our research by identifying their TCM constitutional types by the self testing table of constitutional classification and determination of TCM promulgated by China Association of Chinese Medicine.Hyperuricemia's high-risk constitutional types were analyzed.Results People of dampness-heat constitution (24.57％),phlegm-dampness constitution (22.86％) and static-blood constitution (11.05％) were top 3 groups in occurrence rate of hyperuricemia,the risk ofhyperuricemia in these three groups above were significantly higher than the other constitutional types.On the contrary,the risk of hyperuricemia in the group of the mildly constitution (8.57％) and the group of qi-asthenia constitution (6.29％)were significantly lower than the other groups.Conclusion People of dampness-heat constitution,phlegm-dampness constitution and static-blood constitution were high risk groups of hyperuricemia,which deserved our attention in research of preventive and therapeutic measures for hyperuricemia.
ABSTRACT
Cost accounting is an important measure in hospital economic management.This article approaches the problems and their causes in cost accounting in army hospitals in terms of the correlation between income and cost,the normality of asset management,the accuracy of internal service cost,the advancedness of cost accounting techniques and so on.It also proposes a some corresponding countermeasures based on our work experience.