FAM3A enhances adipogenesis of 3T3-L1 preadipocytes via activation of ATP-P2 receptor-Akt signaling pathway.

FAM3A plays important roles in regulating hepatic glucose/lipid metabolism and the proliferation of VSMCs. This study determined the role and mechanism of FAM3A in the adipogenesis of 3T3-L1 preadipocytes. During the adipogenesis of 3T3-L1 preadipocytes, FAM3A expression was significantly increased. FAM3A overexpression enhanced 3T3-L1 preadipocyte adipogenesis with increased phosphorylated Akt (pAkt) level, whereas FAM3A silencing inhibited 3T3-L1 preadipocyte adipogenesis with reduced pAkt level. Moreover, FAM3A silencing reduced the expression and secretion of adipokines in 3T3-L1 cells. FAM3A protein is mainly located in mitochondrial fraction of 3T3-L1 cells and mouse adipose tissue. FAM3A overexpression increased, whereas FAM3A silencing decreased ATP production in 3T3-L1 preadipocytes. FAM3A-induced adipogenesis of 3T3-L1 preadipocytes was blunted by inhibitor of P2 receptor. In white adipose tissues of db/db and HFD-fed obese mice, FAM3A expression was reduced. One-month rosiglitazone administration upregulated FAM3A expression, and increased cellular ATP content and pAkt level in white adipose tissues of normal and obese mice. In conclusion, FAM3A enhances the adipogenesis of preadipocytes by activating ATP-P2 receptor-Akt pathway. Under obese condition, a decrease in FAM3A expression in adipose tissues plays important roles in the development of adipose dysfunction and type 2 diabetes.

[Caspase1 Inhibitor Ac-YVAD-CMK Prevents and Treats the Acute Graft Versus Host Disease in Mice].

OBJECTIVE: To explore the effect of Caspase 1 inhibitor Ac-YVAD-CMK on acute graft-versus-host disease (aGVHD) after allogeneic hematopoietic stem cell transplantation(allo-HSCT) and its mechanism. METHODS: Experiments were divided randomly into 3 groups: allogeneic hematopoietic stem cell transplantation combined with splenic cell infusion group (TS group, n=12), allogeneic hematopoietic stem cell transplantation combined with splenic cell infusion plus injection of low dose Caspase 1 inhibitor group (TS+low dose of C group, n=16) and plus high dose Caspase1 inhibitor (TS+high dose of C group, n=19). The body weight of mice in each group was dynamically detected, and the clinical manifestation of GVHD and score of aGVHD were determined, and the chimerism rate of mice was detected after transplantation for 14 days. Th1, Th2 and Th17 cells in peripheral blood were examined by flow cytometry. Peripheral proinflammatory cytokines IL-1ß, IFN-γ, IL-1α and IL-18 were examined by enzyme-linked immunosorbent assay(ELISA). The tissues sections of GVHD target organs (liver, lung, colon and skin) were stained with HE for histopathologic examination and histopathologic score. RESULTS: Ac-YVAD-CMK could alleviate murine aGVHD and pathological injury, decreare the incidence and severity of aGVHD in recipient mice. The detection of Th cell subsets in peripheral blood by flow cytometry showed that compared with TS group, the Th1 cell ratio in TS+low dose of C and TS+high dose of C groups was significantly reduced (P<0.05), while the Th2 and Th17 cell ratio was significantly enhanced (P<0.05) in TS+low dose of high dose of C groups. The detection of peripheral inflamematory cytokines by ELISA demonstrated that the inflammatory cytokines including IL-1ß,IFN-γ,IL-18 and IL-1α were reduced significantly (P<0.05). CONCLUSION: Ac-YVAD-CMK can improve aGVHD by inhibiting Caspase 1 and reducing the release of some inflammatory cytokines, thereby alleviated the aGVHD pathological damage.

Sjögren's Syndrome Complicated by Myeloid/Natural Killer Cell Precursor Acute Leukemia: Case Report and Review of the Literature.

We report a case of Sjögren's syndrome (SS) complicated by myeloid/natural killer (NK) cell precursor acute leukemia (M/NKPAL). A 75-year-old woman with a previous SS history for 2 years was routinely treated. Peripheral blood progenitor cells were increased, and subsequent bone marrow cell morphology examination showed the presence of acute myeloid leukemia type M4. However, flow cytometry analysis revealed that CD7/CD56/CD33/CD34/HLA-DR/cCD3 were all positive and myeloperoxidase- (MPO-) specific staining, other T cells, NK cells, and myeloid markers were all negative. Clonal T-cell receptor (TCR)ß/TCRγ/TCRδ gene rearrangements and Epstein-Barr virus (EBV) were negative. The diagnosis of M/NKPAL was therefore confirmed. Unfortunately, this patient did not receive chemotherapy and later died of acute left heart failure and respiratory failure. SS complication with M/NKPAL is relatively rare. Combined with the relevant literatures, our study offers new insights into the clinical characteristics, pathological features, possible pathogenesis, and differential diagnosis of this rare disease.

[Myosin light chain kinase involved in change of intestinal mucosal barrier function in nonalcoholic steatohepatitis mice model].

OBJECTIVE: To investigate the role of myosin light chain kinase (MLCK) in intestinal barrier function in a mouse model with nonalcoholic steatohepatitis (NASH). METHODS: The C57BL/6 mice were randomly divided into five groups including control group, nonalcoholic fatty liver (NAFL) group, NAFL administrated with MLCK inhibitor ML-7 group, nonalcoholic steatohepatitis (NASH) group, NASH administrated with ML-7 group. Plasma ALT and AST were tested. The degree of liver steatosis was assessed by hematoxylin-eosin staining on liver tissue sections.Intestinal mucosal tight junction was observed by electron microscope. The expression of MLCK on intestinal mucosa was detected by immunohistochemistry staining. The level of lipopolysaccharide (LPS) in portal vein was determined by enzyme linked immune sorbent assay (ELISA). The protein and mRNA expression of inflammatory cytokines in liver tissue were tested using ELISA and real-time PCR. RESULTS: MLCK expression in intestinal mucosa was increased in NASH group compared with control group (P<0.01). The tight junctions of intestinal barrier were disrupted in NASH group and intercellular space was larger than control group [(26.60 ± 1.20) nm vs (14.90 ± 0.33) nm, P<0.05], which were improved after ML-7 administration [(14.9 0 ± 0.67) nm]. The LPS in portal vein was higher in NASH group than control group [(7.260 ± 3.184) U/L vs (2.962 ± 0.845) U/L, P<0.05], suggesting that the permeability of intestinal barrier was impaired, however the level of LPS was reduced by ML-7 [(3.772 ± 1.033) U/L, P<0.05]. ALT and AST in plasma, TNFα and IL-6 in liver tissue, the mRNA levels of TNFα and NF-κB in liver tissue were all elevated in NASH group compared with control group (all P<0.05), which were reduced by MLCK inhibitor ML-7. CONCLUSION: Epithelia MLCK probably plays a role in intestinal barrier impairment, which is critical to the pathogenesis of NASH.

G-protein coupled receptor 34 activates Erk and phosphatidylinositol 3-kinase/Akt pathways and functions as alternative pathway to mediate p185Bcr-Abl-induced transformation and leukemogenesis.

Tyrosine 177 and the Src homology 2 (SH2) domain play important roles in linking p185Bcr-Abl to downstream pathways critical for cell growth and survival. However, a mutant p185(Y177FR552L) (p185(YR)), in which tyrosine 177 and arginine 552 in the SH2 domain are mutated, is still capable of transforming hematopoietic cells in vitro. Transplant of these cells into syngeneic mice also leads to leukemogenesis, albeit with a phenotype distinct from that produced by wild-type p185Bcr-Abl (p185(wt))-transformed cells. Here we show that G-protein coupled receptor 34 (Gpr34) expression is markedly up-regulated in p185(YR)-transformed cells compared to those transformed by p185(wt). Knockdown of Gpr34 in p185(YR) cells is sufficient to suppress growth factor-independent proliferation and survival in vitro and attenuate leukemogenesis in vivo. The Erk and phosphatidylinositol 3-kinase/Akt pathways are activated in p185(YR) cells and the activation is dependent on Gpr34 expression. These studies identify Gpr34 as an alternative pathway that may mediate p185Bcr-Abl-induced transformation and leukemogenesis.

Suppression of graft-versus-host disease and retention of graft-versus-tumour reaction by murine genetically engineered dendritic cells following bone marrow transplantation.

The effect of infusion of lentiviral vector­mediated, genetically engineered dendritic cells (DCs) following allogeneic bone marrow transplantation (allo­BMT) on graft­versus­host disease (GVHD) and graft­versus­leukemia (GVL) was investigated in a mouse model. Lentivirus­mediated expression of soluble tumor necrosis factor receptor 1 (sTNFR1) converted immature DCs (imDCs) from BABL/c mice into engineered DCs in vitro. An EL4 leukemia allo­BMT model of BABL/c to C57BL/6 mice was established. Engineered DCs with donor bone marrow cells and splenocytes were subsequently transplanted into myeloablatively irradiated recipients. The average survival duration in the sTNFR1­ and pXZ9­imDC groups was significantly prolonged compared with that of the allo­BMT group (P<0.05). Mild histological changes in GVHD or leukemia were observed in the recipients in the sTNFR1­imDC group and clinical GVHD scores in this group were significantly decreased compared with those of the transplantation and pXZ9­imDC groups. Serum interferon­Î³ levels were decreased in the pXZ9­imDC and sTNFR1­imDC groups compared with those in the allo­BMT group (P<0.05), with the reduction being more significant in the sTNFR1­imDC group (P<0.05). Serum interleukin­4 expression levels were decreased in the allo­BMT group, but gradually increased in the pXZ9­imDC and sTNFR1­imDC groups (P<0.05). Co­injection of donor genetically­engineered imDCs was able to efficiently protect recipient mice from lethal GVHD while preserving GVL effects during allo­BMT.

[Effect of interfering the ß-catenin by lentiviral vector-mediated RNAi on the biological behavior of mouse bone marrow mesenchymal stem cells].

This study was aimed to investigate the effect of Wnt/ß-catenin signaling pathway on the biologic behavior of mouse bone marrow mesenchymal stem cells (mBM-MSC) by constructing a RNAi lentiviral vector specific to ß-catenin. Three pairs of shRNA coding sequences directed against different sites of ß-catenin mRNA were designed and were linked into lentiviral vector plasmid PLB for constructing the PLB-ß-catenin/shRNA1, PLB-ß-catenin/shRNA2 and PLB-ß-catenin/ shRNA3. Those plasmids and lentiviral packaging plasmids were co-transfected into the packaging cells 293FT, then the virus particles were collected and the viral titer was assayed after concentration, and these viral particles were infected to MSC. The flow cytometry was used to sort GFP (+) cells, Western blot and RT-PCR were used to verify the inhibitory effect of those cells on expression of ß-catenin gene in cells, CCK-8 method was used to detect the cell proliferation level, Annexin-V/7-AAD was used to determine the cell apoptosis after interference, the cell scratch and transwell tests were used to detect the migration capability of MSC. The results showed that the efficient inhibition of ß-catenin mRNA and protein expression, and the suppression of MSC proliferation were observed in group of PLB-ß-catenin/shRNA2 (interference group), while there was no significant changes of MSC proliferation between negative group (PLB group) and the normal group (control group). The flow cytometric detection indicated that after induced by serum starvation for 72 h, the apoptosis of MSC increased in interference group, but there was no difference between PLB and control groups (P > 0.05). The cell scratch and transwell tests demonstrated that the migration capability of MSC in interference group decreased significantly, while the migration capability of MSC in control group was not changed obviously. It is concluded that the constructed specific RNAi lentivirus can effectively inhibit the expression of ß-catenin gene, decrease expression level of ß-catenin mRNA and protein. The Wnt/ß-catenin signaling pathway plays an important role in biological behavior of BM-MSC.

[Effects of immature dendritic cells to express CCR7 on graft-versus-host disease in allogeneic bone marrow transplant mouse model].

OBJECTIVE: To investigate the effects of immature dendritic cells (imDC) expressing chemokine receptor-7 (CCR7) on acute graft-versus-host disease (aGVHD) in allogeneic bone marrow transposed (allo-BMT) mouse model. METHODS: We constructed the lentiviral vectors carrying mouse CCR7 gene and infect imDC effectively in vitro. GVHD model was established with C57BL/6(H-2b) donor mice and BALB/c (H-2d) recipient mice. After irradiation, recipients were injected with donor bone marrow and spleen cells along with CCR7-modified dendritic cells. Mice were randomized into irradiation, transplant control, pXZ9-imDC (empty vector control) and CCR7-imDC groups. Survival, GVHD score, histopathological analysis and plasma levels of inflammatory cytokines were observed. RESULTS: The mean survival in irradiation, transplantation, pXZ9-imDC and CCR7-imDC groups were (8.20±1.48)d, (12.20±2.78)d, (20.70±6.01)d and (27.5±7.55)d respectively. The survival in CCR7- imDC group was significantly improved compared with other groups (P<0.05). GVHD scores in transplantation, pXZ9-imDC and CCR7-imDC groups were (6.90±1.66), (5.60±0.97) and (4.10±1.79) respectively. CCR7-imDC group had significantly lower GVHD score and minor tissue damages shown by histopathological analysis than the other groups. Plasma IFN-γ level increased and reached the peak at +10 day in transplant group, while it gradually decreased in pXZ9-imDC and CCR7-imDC groups, and then reached the nadir at +20 day post-allo-BMT, with the lowest level in CCR7-imDC group (P<0.01). Plasma IL-4 decreased in transplant group, while it gradually increased in pXZ9-imDC and CCR7-imDC groups and reached the highest level at + 10 day in CCR7- imDC group (P<0.01). The 95%-100% of H-2b positive cells in recipient mice on + 30 day post-allo-BMT demonstrated the complete donor- type implantation. CONCLUSION: Genetically modified immature DC by CCR7 gene could alleviate damages by GVHD and prolong survival of recipient mice after allo-BMT.

[Effect of different therapeutic regimens on regulatory T cells in patients of primary immune thrombocytopenia].

OBJECTIVE: To investigate the change of CD4⁺CD25(high)CD127(low) regulatory T cells (Tregs) percentage in patients with primary immune thrombocytopenia (ITP) treated by different methods. METHODS: One hundred and thirty-eight newly diagnosed adult ITP patients (57 male, median age 40 years, range 18-70 years) were enrolled in this study, who were randomly separated into three regiment groups, namely prednisolone (PSL, 1.5 mg/kg for 2-4 weeks and subsequently stepwise reduction) group enrolled 49 patients, dexamethasone [(one course of high-dose dexamethasone (HDD) 40 mg/day, d1-4] 45 patients, and rituximab plus HDD (rituximab 100 mg on days 7, 14, 21, 28 and HDD) group 44 patients. Peripheral blood was taken in ITP patients of each group before treatment, 14 d and 28 d after treatment. The percentages of CD4⁺CD25(high)CD127(low) Tregs in 30 healthy controls and 138 patients were analyzed by flow cytometry. RESULTS: Overall response (OR) rates of PSL, HDD and R+HDD groups at day 28 were 69.4%, 66.7% and 79.5% respectively with no difference. After the following 12 months, sustained response (SR) was more pronounced in R+HDD group compared to the other two groups (R+HDD vs PSL: 66.7% vs 37.8%, P<0.05; R+HDD vs HDD: 66.7% vs 22.7%, P<0.05). The percentage of CD4⁺CD25(high)CD127(low) Tregs in peripheral blood of ITP patients [(1.67±0.70)%] was significantly lower than in healthy control group; After treatment, the percentages of Tregs in peripheral blood of patients both at day 14 and 28 in R+HDD group remarkably decreased compared with before treatment [(4.28±1.09)% vs (1.68±0.68)%, P<0.05; (4.44±0.63)% vs (1.68±0.68)%]. The percentages of Tregs at day 14 in both other two groups decreased notably compared with before treatment. But the Tregs levels measured at day 28 in PSL and HDD groups were similar with before treatment. CONCLUSION: The percentage of CD4⁺CD25(high)CD127(low) Tregs in peripheral blood of ITP patients was lower than healthy individual. The higher SR of patients treated by R+HDD was related to its ability to up-regulate the percentage of CD4⁺CD25(high)CD127(low) Tregs.

Upregulation of GPR34 expression affects the progression and prognosis of human gastric adenocarcinoma by PI3K/PDK1/AKT pathway.

PURPOSE: G-protein coupled receptor 34 (GPR34), which belongs to the G-protein coupled receptors superfamily, is reportedly expressed highly in the spread of several solid tumors. However, its expression in gastric primary tumor and potential role in gastric cancer development and progression have not been determined. METHODS: Immunohistochemistry, real-time RT-PCR and western blot methods were used to determine GPR34 expression in human gastric cancer tissues/cell lines and matched adjacent tissues/ normal mucosal cell line. A statistical analysis was performed to establish the potential correlation between GPR34 expression and the patients' clinicopathological characteristics, tumor progression, and prognosis. Stably transfected NCI-N87 cell lines with either GPR34 over-expression or knock-down were constructed to determine the effect of GPR34 on gastric cancer cell invasion and migration, and to explain the preliminary molecular mechanism of GPR34 in gastric cancer metastasis. RESULTS: GPR34 is up-regulated in primary gastric cancer tissues/cell lines compared with matched adjacent tissues/normal mucosal cell line, and when the relationship between GPR34 expression and the the clinicopathological characteristics was analyzed, it was shown that GPR34 expression is significantly correlated with tumor differentiation, infiltration depth, and lymph node status and had a significant influence on prognosis. Furthermore, GPR34-overexpression increased while GPR34-knockdown inhibited NCI-N87 cell invasion in vitro by PI3K/PDK1/AKT pathway. CONCLUSIONS: Taken together, up-regulation of GPR34 expression in human gastric carcinoma may play a critical role in tumor progression and in determining patient prognosis. GPR34 may be a useful diagnostic or prognostic molecular biomarker, and a potential target for therapeutic intervention.

[Construction of shRNA expression vector targeting AATF and establishment of stably transfected U937 cells].

This study was aimed to construct the targeting AATF shRNA eukaryotic expression vector and establish the stably transfected U937 cell lines. The sequence of AATF mRNA was obtained from GenBank. After excluding homology, three plasmid expression vectors coding shRNA targeting 228 ∼ 249, 303 ∼ 324 and 443 ∼ 464 of AATF gene sequence were synthesized. Two terminals of shRNA carried BamHI and HindIII restriction sites. The selected nucleotides were cloned into the plasmid pSilencer 3.1-H1 neo respectively, and the resultant recombinant plasmids were named as pSA-1, pSA-2, pSA-3. The sequences of the recombinant plasmids were identified by DNA sequencing. The recombinant plasmids were transfected into the cell line U937 by electroporation with Neon(TM) Transfection System. The transfected cells were persistently screened under G418 (500 mg/L), and isolated with a limited dilution for 8 weeks. The inhibition of AATF mRNA and protein expression was respectively detected by RT-PCR and Western blot. The results indicated that RNAi eukaryotic expression vectors targeting AATF had correct reading frame and nucleotide sequence. Real-time PCR revealed that AATF shRNA effectively silenced mRNA expression of AATF. Western blot analysis found that AATF shRNA obviously suppressed protein expression of AATF (P < 0.05). It is concluded that the shRNA eukaryotic expression vector has been successfully constructed which can inhibit the expression of AATF, and the establishment of stably transfected U937 cell lines provide a original route for exploring the mechanism of AATF in human Leukemia further.

[Efficacy and safety of low-dose rituximab combined with different dosage of glucocorticoids for immune thrombocytopenia].

OBJECTIVE: To compare the efficacy and safety of low-dose rituximab combined with different dosage of glucocorticoids for immune thrombocytopenia (ITP). METHODS: Seventy-four patients (35 male, median age 34 years, range 18-70 years) including 60 newly-diagnosed, 6 persistent, 5 chronic and 3 refractory patients were enrolled in this study, and separated into control (36 cases) and experimental (38 cases) groups according to the dosage of glucocorticoids. Patients in both groups received dexamethasone 40 mg/day on days 1-4, followed by rituximab 100 mg on days 7, 14, 21, 28. The patients in experimental group also received decrements of prednisone 60, 30, 20, 10 mg/day on days 5-7, 8-14, 15-21, 22-28. The initial, long-term efficacy and safety were evaluated. RESULTS: Platelet counts of all patients at day 4 remarkably increased, with the median platelet count from 11(1-26) × 109/L to 84(23-132) × 109/L in control group, and 10(2-20) × 109/L to 80(22-115) × 109/L in experimental group; the platelet counts of patients at day 14 in experimental group [163(19-262) × 109/L] was higher than that of control group [98(18-238) × 109/L] (P<0.05). The overall response (OR) rates at day 28 in experimental group (84.21%) was significantly higher than that of control group (66.67%, P = 0.03). There was no significant difference of sustained response (SR) rates in two groups (63.89%vs 65.79%, 58.33%vs 60.53%, P > 0.05) at six and twelve months follow-up points. Both groups showed similar incidence of adverse events, and no patients discontinued the treatment due to side effects. CONCLUSION: Low-dose rituximab and glucocorticoids was an effective method for ITP patients, and maintenance treatment with decrements of prednisone contributed to improving earlier CR rate.

HOXA9 gene expression in acute myeloid leukemia.

Homeobox genes encode the class of transcription factors in vertebrates and are found in clusters called A, B, C, and D on four separate chromosomes. HOXA9 gene is part of the cluster A on chromosome 7 and encodes a DNA-binding transcription factor which may regulate gene expression, morphogenesis, and differentiation. The objective of this study was to determine the HOXA9 gene expression in acute myeloid leukemia (AML). For this purpose, semi-quantitative reverse transcriptase-polymerase chain reaction was used to measure HOXA9 gene expression in human erythroleukemia (HEL) cell line and bone marrow mononuclear cells from 54 AML patients and 20 healthy individuals. The data show that HOXA9 mRNA expression was negative in 20 healthy individuals but was positive in HEL cells and in 22 out of 54 (40.74%) AML patients. The complete remission rate (45.45%) of the patients who expressed the gene was significantly lower than that (71.86%) in patients who did not express the gene after chemotherapy. Therefore, it was concluded that HOXA9 gene might be involved in the pathogenesis of AML and played as a worse prognostic factor in AML.

Prevention of acute GVHD in mice by treatment with Tripterygium hypoglaucum Hutch combined with cyclosporin A.

OBJECTIVE: To elucidate the protective roles and the underlying mechanism of Tripterygium hypoglaucum Hutch (THH) in mice graft-versus-host disease (GVHD). METHODS: BALB/c (H-2k(d)) mice were firstly treated with total body irradiation and infused with a mixture of bone marrow and spleen cells from C57BL/6. Then the severity of acute GVHD (aGVHD), chimeras of donor cells, inflammatory cytokines (IFN-γ, IL-4, and IL-10) of plasma, and regulatory T cells were evaluated to elucidate the different drug combinations and concentrations of cyclosporin A (CsA) and THH in preventing aGVHD. RESULTS: The control group treated with phosphate buffer solution displayed more obvious ruffled hair, hunched posture, diarrhea, reduced weight and more lymphocytes infiltration into the spleen and intestine than these treated with CsA, THH or low-dosed CsA combined with THH, especially those treated with low-dosed CsA combined with THH. No significant differences were observed in the chimeras of donor cells and survival rate among the CsA, THH, or CsA combined with THH-treated groups. Further studies implied that THH might reduce the aGVHD by increasing IL-10, decreasing IL-4, activating Treg cell, and maintaining a relatively high Foxp3 mRNA level. CONCLUSION: THH decreased the occurrence of mouse aGVHD and prolonged the survival time by increasing the levels of CD(4)(+)/CD(25)(+) T cells, regulating the cytokine secretion and promoting the expression of Foxp3.

[Expression of interleukin-22 and relative CD4(+) T cell subsets in patients with immune thrombocytopenia].

The aim of this study was to detect the expression of interleukin-22 (IL-22) and relative CD4(+) T cell subsets in untreated adult patients with immune thrombocytopenia (ITP), and to explore their roles in the pathogenesis of ITP. Fourty adult active ITP patients were enrolled in this study and 40 healthy subjects were taken as control. Plasma IL-22 level was quantified by ELISA. The percentages of Th1, Th17 and Th22 cells in peripheral blood were determined by flow cytometry. The Pearson correlation test was used to evaluate correlations between IL-22 level and Th1 cells, Th17 cells and Th22 cell percentages. The results showed that the plasma IL-22 levels in untreated ITP patients [(364.12 ± 94.22) pg/ml] were significantly higher than that in healthy controls (P < 0.001). The percentages of both Th1 [(18.92 ± 6.03)%] and Th22 [(2.28 ± 0.51)%] cells in ITP patients were elevated as compared to healthy controls (P < 0.05). Elevated plasma concentration of IL-22 positively correlated to the percentages of Th1 (r = 0.42, P = 0.022) and Th22 (r = 0.40, P = 0.030) cells in untreated ITP patients. The percentage of Th17 cells was not significantly different between untreated patients and normal controls, and there was no statistical correlation between the IL-22 level and the percentage of Th17 cells in active ITP patients. It is concluded that elevated IL-22 level correlates to Th1 and Th22 cells percentage, which may play a synergistic effect in the immunopathogenesis of ITP, while Thl7 cells may not be associated with the occurrence of active ITP.

[Propagation of prdm1 gene knockout mouse and its genotype identification].

This study was aimed to propagate and identify the prdm1 gene-knockout mice, so as to lay the foundation for studying Blimp-1 protein. Two kinds of transgenic homozygous mice with B6.prdm1(flox/flox) and B6.Lck-Cre were feed and propagated; after successful propagating, the first passage mice were obtained; after the first passage mice were copulated once again, the genotypes were obtained as follows: B6. prdm1(wild/wild). Lck-Cre, B6. prdm1(wild/wild), B6.prdm1(flox/flox). Lck-Cre, B6.prdm1(flox/wild). Lck-Cre, B6.prdm1(flox/flox), B6. prdm1(flox/wild). The genomic DNA of second passage mice was extracted, the Cre and loxp gene fragments were amplified by PCR, then the size of Cre and loxp genomic DNA were detected by agarose gel electrophoresis. The mice with B6.prdm1(flow/flox). Lek-Cre were used as conditionally prdm1-knockout mice, B6.prdm1(flox/wild). Lck-Cre mice, B6.prdm1(flox/flox) and B6 mice were used as controls. The spleen T lymphocytes and B lymphocytes were sorted by using magnetic beads, the blimp-1 target protein was identified by Western blot. The results showed that the two transgenic homozygous mice had the ability to reproduce, and the separation ratio of second passage mice generated from propagation of their offspring cach other meet Mendelian laws, and the prdm1 gene-knockout mice also could successfully obtained. It is concluded that the application of Cre-loxp system may successfully obtain plentiful prdm1 gene-knockout mice.

[Effects of immature dendritic cells genetically modified to express sTNFR I on graft-versus-host disease (GVHD) and graft-versus-leukemia (GVL) in allogeneic bone marrow transplantation mice].

OBJECTIVE: To investigate the effect of immature dendritic cells (inDC) genetically modified to express sTNFR I on acute graft-versus-host disease (aGVHD) and the graft-versus-leukemia (GVL) effect ofter allogeneic bone marrow transplantation (allo-BMT) in leukemic mice and its mechanism. METHODS: An EL4 leukemia allo-BMT model was established with the BALB/c (H-2d) donor mice (DM)and C57BL/6 (H-2b) recipient mice (RM). The RM received DM bone marrow (BM) cells at a 1:1 ratio with spleen cells intravenously via tail vein at 4 h after TBI. Fifty DM were separated randomly into five groups: (1) Group A: total body irradiation (TBI) group, (2) Group B: lymphoma cell leukemia group, (3) Group C: allo-BMT group, (4) Group D: pXZ9-DC group, (5) Group E: sTNFR I-DC group. Acute GVHD scores, incidence of leukemic cell infiltration, histopathological analysis, survival rate, and survival rate of the recipients were estimated after allo-BMT. Enzyme-linked immunosorbent assay (ELISA) method was used to detect cytokines (INF-gamma and IL-4 ) production. Flow cytometry (FCM) analysis was used to detect allogeneic chimerism. RESULTS: (1) The mice in group A and group B all died of the BM failure and lymphoma cell leukemia, respectively. The mice in group C developed typical clinical signs of a GVHD after BMT with an average survival time(AST) of (11.50 +/- 3.50) d. The signs of aGVHD were less evident in the group D and E, and their AST (21.70 +/- 5.80 and 25.80 +/- 5.20 days, respectively) were all longer than that in group C (P < 0.05). AST of group E was the longest (P < 0.05). The mice in group B all died of leukemia within 18 days after engraftment of EL4 cells. There was was no significant difference in groups C, D and E in the incidence of leukemia (P > 0.05). (2) Serum IFN-gamma level reached peak value. At + 12 d, then decreased gradually in group C, D, and E, and then reached the nadir at +18 d post-BMT, with the lowest in group E (P < 0.05), and the level was significantly lower in group D than in group C (P < 0.05). After BMT, serum IL-4 level slightly decreased in group C, but gradually elevated in group D and E and reached their peak at +12 d, and even more significantly increased in group E (P < 0.05). There was no statistical significance in the pair wise comparison among three group (P < 0.05). (3) The average proportion of H-2d positive cells in RM was 95%-100% on day 30 post-BMT, with complete donor-type implantation. CONCLUSION: Immature DC can induce immuno tolerance. Immature DC genetically modified to express sTNFR I has been shown to prevent acute GVHD in lethally irradiated mice reconstituted with allogeneic bone marrow grafts while maintaining the GVL response.

[In vitro effects of Wnt3a gene modification on mitigating damage of mouse bone marrow mesenchymal stem cells induced by Ara-C].

This study was aimed to investigate the protective effect of Wit3a gene modification on mouse bone marrow mesenchymal stem cells against the injury induced by Ara-C. The gene-modified MSC steadily expressing Wnt3a were established by adenovirus system. The acute direct damage effects of different concentrations of Ara-C on the unmodified MSC and the gene-modified MSC were assessed by using an in vitro culture system, and the corresponding controls were set. The proliferation and apoptosis of MSC exposed to Ara-C were detected by cell count kit-8 (CCK-8) and flow cytometry. The expression of BCL-2 protein related with cell apoptosis was assayed by Western blot. The results indicated that as compared with unmodified MSC, Ara-C exhibited a less inhibitory effect on the proliferation of gene-modified MSC. There was obvious difference between unmodified MSC and gene-modified MSC (p < 0.05). The proliferation of gene-modified MSC began to recover at 72 hours after removal of Ara-C. However, unmodified MSC showed sustained suppression of proliferation after withdrawal of Ara-C. In apoptosis, the apoptosis rate of gene-modified MSC induced by Ara-C was significantly lower than those of unmodified MSC (p < 0.05). In addition, the expression levels of BCL-2 protein in gene-modified MSC were up-regulated compared with unmodified MSC (p < 0.05). It is concluded that Wnt3a gene modification can significantly mitigate the damage of mouse bone marrow MSC induced by Ara-C.

[Influence of mouse genetic engineering regulatory T cells infusion on post-allogeneic bone marrow transplantation acute graft-versus-host disease in mice].

OBJECTIVE: To explore the influence of the lentiviral vector mediated mouse genetic engineering regulatory T cells (Treg) infusion on post-allogeneic bone marrow transplantation (allo-BMT) acute graft-versus-host disease (GVHD) in mice. METHODS: Lentivirus-mediated Forkhead box P3 (Foxp3) gene was transduced into BALB/c mice CD4(+)CD25(-) T cells (Treg) to construct engineered Tregs in vitro. An allo-BMT model of BALB/c to C57BL/6 mice was established. After irradiation, the recipients were injected with donor cells plus the genetic engineering Tregs. Survival time, clinical GVHD score, histopathological findings, activation of donor T cells or serum levels of inflammatory cytokines were observed after allo-BMT. RESULTS: The mean survival times for radiation alone group (Gp I), transplantation control group (Gp II), engineering Treg infusion group (Gp III) and empty vector control group (Gp IV) were (8.8 ± 0.6) d, (36.7 ± 2.5) d, (51.6 ± 4.0) d and (34.1 ± 2.3) d, respectively. The survival time was significantly longer in Gp III than in other groups (P < 0.05). Histopathological finding in several target organs (skin, liver and small intestine) confirmed the presence of severe GVHD in Gp II and Gp IV, while no histological signs of GVHD were observed in long survival recipients in Gp III, and clinical GVHD scores in Gp III were significantly lower than that in Gps II and IV. The numbers of donor T cells and the percentage of IFN-producing donor T cells in the spleen of recipients in Gp III were significant lower than those in Gps II and IV at days 3 and 4, and at day 3 after transplantation, respectively (P < 0.05). The serum levels of IFN-γ, IL-2 and TNF-α were increased at day 21 to 28 after transplantation in all groups. The peak concentrations of IFN-γ, IL-2 and TNF-α in Gp III were significantly lower than those in Gps II and IV control groups at day 21 (P < 0.05). CONCLUSION: Co-injection of genetic engineering Treg can efficiently prevent recipients from lethal GVHD after allo-BMT in mice by inhibiting the early activation and expansion of donor T cells and reducing the serum levels of inflammatory cytokines.