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Aiping Qi,
Hu Zhou,
Zeping Zhou,
Xin Huang,
Li Ma, Hongmei Wang,
Yanhui Yang,
Donglei Zhang,
Huyuan Li,
Ruimin Ren,
Renchi Yang
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ABSTRACT: OBJECTIVES: To evaluate the telomere/telomerase system and its clinical significance in immune thrombocytopenia (ITP) patients. METHODS: A total of 237 ITP patients, 20 SLE patients and 200 age-and sex-matched healthy controls were included in this study. CD4(+), CD8(+) and CD19(+) lymphocytes were purified by magnetic beads sorting from peripheral blood of 37 active chronic ITP patients and 22 age-and sex-matched healthy controls. Telomerase activity was assayed by Telo TTAGGG Telomerase PCR ELISA KIT. The relative telomere length of peripheral blood mononuclear cell (PBMC) was measured by a quantitative polymerase chain reaction-based method (Q-PCR) from 200 ITP patients and 178 age-and sex-matched healthy controls. RESULTS: Telomerase activity was increased in CD4(+), CD8(+) and CD19(+) lymphocytes from ITP patients compared to those from healthy controls (p = 0.000). The level of telomerase activity in CD19(+) lymphocyte was higher than those in CD4(+) and CD8(+) lymphocytes. Telomerase activity of CD19+ lymphocytes had a modest negative correlation with platelet count in ITP patients (p = 0.042). The relative telomere length of PBMC in ITP patients was significantly shorter than that in the healthy controls (p = 0.002). Telomere length of PBMC in active ITP patients was significantly shorter than that in the controls (p = 0.000) and a tendency to be shorter even in inactive ITP patients (p = 0.065). Moreover, the telomere length in refractory and non-refractory ITP patients were both significantly shorter than that in the controls (p = 0.025; p = 0.000). However no significant difference in telomere length of PBMC was found between refractory ITP patients and non-refractory ITP patients (p = 0.234). CONCLUSION: An abnormal regulating telomere/telomerase system might be involved in the pathogenesis of ITP. Further studies may elucidate whether the telomere length could be considered as a predictive biomarker for the prognosis of ITP.
Journal of Clinical Immunology 12/2012; · 3.08 Impact Factor
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ABSTRACT: Immune thrombocytopenia (ITP), often diagnosed in the elderly, is a hematologic disorder induced by autoimmune mechanism. In this retrospective study, we evaluated the clinical features, the risk of bleeding, and the response to treatment in 525 elderly ITP patients (age ≥60 years) diagnosed at our center from 1980 to 2009. There were more females at 60-74 years of age (P = 0.044). The median duration of follow-up was 27 months (range 1-253 months). Ten patients developed thrombosis during treatment of ITP. At diagnosis, 461 patients (87.8 %) had signs of bleeding. The risk of severe bleeding was associated with both platelet count (P < 0.001; odds ratio (OR), 0.973) and age (P = 0.025; OR, 1.039). The cutoff points in the platelet count at which bleeding and severe bleeding would begin to appear were 29.5 × 10(9) and 21.5 × 10(9)/L, respectively. Sixteen of 144 patients (11.1 %) who did not receive any treatment achieved remission spontaneously. The total response rate to treatment was 62.4 % (166/266). The median time to remission was 7 days, and combined use of intravenous immunoglobulin and steroids took effect faster than use of steroids alone (P = 0.001). Fifty-two patients (31.3 %) relapsed during follow-up. Of the 27 patients who died during follow-up, seven deaths were directly attributed to ITP. In conclusion, the response rate has been improved since the last 10 years. ITP is also a self-limited disease to some extent in the elderly, but easy to relapse. This review represents the largest collection of elderly ITP patients in China in a single center.
Annals of Hematology 09/2012; · 2.62 Impact Factor
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ABSTRACT: A 28-year-old man complained of intermittent irritable dry cough for 2 months with occasional bloody sputum. Positron emission tomography-computed tomography (PET-CT) suggested multiple heterogeneous soft tissue masses in the inferior lobes of both lungs, with heterogeneous increases in (18)F-FDG uptake. No metabolic disorders were found in the rest of the body. CT-guided percutaneous lung puncture and biopsy and immunohistochemical study confirmed pulmonary primitive neuroectodermal tumor (PNET). PNET is characterized by small round blue cells and positive CD99 expression. After six cycles of chemotherapy with ifosfamide, dacarbazine and cisplatin, the lesions diminished substantially. At 2 months after the last cycle of chemotherapy, the patient complained of exertional dyspnea. PET-CT and echocardiogram suggested a space-occupying lesion in the right atrium. Autopsy revealed that this space-occupying lesion had the same pathomorphology and immunophenotype with pulmonary PNET, suggesting metastasis of pulmonary PNET to the right atrium. Here, we reported this rare case of pulmonary PNET metastasizing, instead of direct infiltrating or extending, into the heart.
Medical Oncology 03/2012; 29(4):2649-53. · 2.14 Impact Factor
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ABSTRACT: Cortisol is transported by corticosteroid-binding globulin (CBG) in blood. Single nucleotide polymorphisms (SNP) in the human CBG (SERPINA6) gene that disrupt CBG production or steroid binding are considered rare.
The objective of the study was to identify and determine the frequency of SNP in SERPINA6 that influence the production or cortisol-binding properties of CBG in Chinese subjects.
Blood samples from 2287 anonymous Chinese workers undergoing routine health tests were screened for the SERPINA6 coding sequence polymorphisms.
In a pilot study of 108 Chinese women, two nonsynonymous SNP were identified within SERPINA6 exon 2 encoding CBG A51V (n = 3) and CBG E102G (n = 1) variants. Sequence analysis of SERPINA6 exon 2 in a further 137 Chinese women revealed two other individuals with nonsynonymous SNP encoding CBGs R64Q and R64W as well as another CBG A51V carrier. The surprisingly high frequency of heterozygous CBG A51V carriers was confirmed in 1011 Chinese men (1:35) and 1031 other women (1:37). Individuals homozygous for these SNP were not identified. When expressed in Chinese hamster ovary cells, CBG A51V bound steroid normally, but its production/secretion was severely impaired; CBG E102G was produced normally, but its cortisol-binding capacity was abnormally low, whereas CBG R64Q and R64W were produced and bound cortisol normally.
Defects in CBG A51V production explain why plasma CBG levels in individuals heterozygous for this variant are approximately 50% lower than normal. The high frequency of CBG A51V will allow clinical consequences of CBG deficiencies to be assessed for the first time in large patient populations.
The Journal of clinical endocrinology and metabolism 02/2012; 97(4):E678-86. · 6.50 Impact Factor
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ABSTRACT: Autoreactive T cells in immune thrombocytopenia(ITP) patients undergo a rapid clonal expansion and are resistant to apoptosis to maintain continuous effect in thrombocytopenia. As Bmi-1 is involved in memory CD4+ T cell survival and Th2 proliferation, we hypothesized that Bmi-1 may have a role in autoreactive CD4+ T cell clonal expansion and Th1/Th2 development in ITP patients. We found that CD4+ T cells from active ITP patients had a higher Bmi-1 expression in comparison with remission and healthy controls, and autoreactive CD4+ T cells had more capability to proliferate and resistance to apoptosis than that of healthy controls. We evaluated the part that Bmi-1 played in proliferation and Th1 bias condition of autoreactive CD4+ T cells in ITP. We used lentiviral transfer vectors containing Bmi-1 and shBmi-1 to infect CD4+ T cells from ITP patients and healthy controls during autologous platelets stimulation. Flow cytometry and ELISA were applied to detect various parameters. The results showed that suppression of Bmi-1 using short hairpin RNA inhibited the platelet-mediated proliferation and increased apoptosis of autoreactive CD4+ T cells from ITP patients.Increased Bmi-1 expression in CD4+ T cells from healthy controls promoted the proliferation and inhibited apoptosis of CD4+ T cells. Bmi-1 significantly promoted interleukin-4 secretion by CD4+ T cells. These findings suggest that Bmi-1 plays a part in autoreactive CD4+ T cell proliferative capability and apoptotic resistance in ITP patients.
Journal of Clinical Immunology 02/2012; 32(3):505-13. · 3.08 Impact Factor
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Nan Jiang,
Xusheng Zhang,
Xiufen Zheng,
Di Chen,
Kingsun Siu, Hongmei Wang,
Thomas E Ichim,
Douglas Quan,
Vivian McAlister,
Guihua Chen,
Wei-Ping Min
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ABSTRACT: Fulminant hepatitis progresses to acute liver failure (ALF) when the extent of hepatocyte death exceeds the liver's regenerative capacity. Although small interfering RNA (siRNA) appears promising in animal models of hepatitis, the approach is limited by drawbacks associated with systemic administration of siRNA. The aim of this study is to develop a hepatocyte-specific delivery system of siRNA for treatment of fulminant hepatitis.
Galactose-conjugated liposome nano-particles (Gal-LipoNP) bearing siRNA was prepared, and the particle size and zeta potential of Gal-LipoNP/siRNA complexes were measured. The distribution, cytotoxicity and gene silence efficiency were studied in vivo in a concanavalin A (ConA)-induced hepatitis model. C57BL/6 mice were treated with Gal-LipoNP Fas siRNA by i.v. injection 72 h before ConA challenge, and hepatocyte injury was evaluated using serum alanine transferase (ALT) and aspartate transaminase (AST) levels, as well as liver histopathology and TUNEL-positive hepatocytes. The galactose-ligated liposomes were capable of encapsulating >96% siRNA and exhibited a higher stability than naked siRNA in plasma. Hepatocyte-specific targeting was confirmed by in vivo delivery experiment, in which the majority of Gal-LipoNP-siRNA evaded nuclease digestion and accumulated in the liver as soon as 6 h after administration. In vivo gene silencing was significant in the liver after treatment of Gal-Lipo-siRNA. In the ConA-induced hepatitis model, serum levels of ALT and AST were significantly reduced in mice treated with Gal-lipoNP-siRNA as compared with control mice. Additionally, tissue histopathology and apoptosis showed an overall reduction of injury in the Gal-LipoNP siRNA-treated mice.
This study is the first to our knowledge to demonstrate reduction of hepatic injury by liver-specific induction of RNA interference using Gal-LipoNP Fas siRNA, highlighting a novel RNAi-based therapeutic potential in many liver diseases.
PLoS ONE 01/2012; 7(9):e44138. · 4.09 Impact Factor
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Rong Li,
Xiufen Zheng,
Igor Popov,
Xusheng Zhang, Hongmei Wang,
Motohiko Suzuki,
Rosalia De Necochea-Campion,
Peter W French,
Di Chen,
Leo Siu,
David Koos,
Robert D Inman,
Wei-Ping Min
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ABSTRACT: We have previously demonstrated that immune modulation can be accomplished by administration of gene silenced dendritic cells (DC) using siRNA. In this study, we demonstrate the therapeutic utilization of shRNA-modified DC as an antigen-specific tolerogenic vaccine strategy for autoimmune arthritis.
A shRNA that specifically targets IL-12 p35 was designed and cloned into a plasmid vectors (IL-12 shRNA). Bone marrow-derived DC from DBA/1 mice were transfected with the IL-12 shRNA construct in vitro. Mice with collagen II (CII)-induced arthritis (CIA) were treated with the modified DCs expressing the shRNA. Recall response and disease progression were assessed.
After gene silencing of IL-12 in DC, DC were shown to selectively inhibit T cell proliferation on recall responses and in an MLR. In murine CIA, we demonstrated that administration of IL-12 shRNA-expressing DC that were pulsed with CII inhibited progression of arthritis. The therapeutic effects were evidenced by decreased clinical scores, inhibition of inflammatory cell infiltration in the joint, and suppression of T cell and B cell responses to CII.
We demonstrate a novel tolerance-inducing protocol for the treatment of autoimmune inflammatory joint disease in which the target antigen is known, utilizing DNA-directed RNA interference.
Journal of Translational Medicine 01/2012; 10:19. · 3.41 Impact Factor
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ABSTRACT: CD70 (TNFSF7), as a methylation susceptive immune gene, was hypomethylated in some autoimmune diseases. To investigate the status of CD70 methylation and the expressions of genes that regulated methylation in immune thrombocytopenia (ITP) patients, the expressions of CD70 mRNA and protein in CD4(+) T cells from ITP and controls were measured respectively by real-time PCR and flow cytometry. Methylation specific high resolution melting (MS-HRM) technology was applied to detect CD70 promoter methylation indices. Transcription levels of DNA methyltransferases (DNMTs), methylated CpG binding protein 2 (MBD2) were measured. The results showed that CD70, DNMTs and MBD2 was over expressed and methylation indices of CD70 promoter in CD4(+) T cells from ITP patients were lower than that from healthy controls. The transcription levels of CD70 showed significantly inverse correlation with methylation indices in ITP patients but significantly positive correlation with that of DNMTs. We concluded that DNMTs functioned as demethylases as MBD2, while increased DNMTs and MBD2 may cause demethylation and over expression of CD70 in CD4(+) T cells, potentially contributing to the pathogenesis of ITP.
Molecular Immunology 07/2011; 48(12-13):1525-31. · 2.90 Impact Factor
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ABSTRACT: CD70 and CD11a are co-stimulatory molecules that are important for the immune functions of T, B lymphocytes. Over-expressions of CD70 or CD11a cause T cell to be autoreactive.
The purpose of this study was to explore the effect of CD70 and CD11a in immune thrombocytopenia (ITP).
CD70 and CD11a mRNAs and protein expressions in CD4(+) T cells from ITP patients were measured respectively by real-time quantitative-PCR (RT-PCR) and flow cytometry. The apoptosis of T cells, B cells, and platelets in the PBMCs were analyzed by flow cytometry, and secretion of IL-4, IFN-γ, as well as IgG in the reaction supernatant were detected by ELISA. In order to investigate the effects of CD70 and CD11a over-expression on pathogenesis of ITP, anti-CD70, and anti-CD11a mAbs were used to block the signaling pathways.
CD70 and CD11a mRNAs and protein expressions in CD4(+) T cells from ITP patients were significantly higher than healthy controls. In vitro co-culturing of PBMCs with anti-CD70 or anti-CD11a, the apoptosis of T, B lymphocytes were significantly increased but apoptosis of platelets were reduced. Anti-CD11a and anti-CD70 both significantly suppressed the secretion of IFN-γ, while anti-CD11a significantly promoted the secretion of IL-4. There was no significant difference in the healthy group.
CD70 and CD11a facilitate the survival of T, B lymphocytes and indirectly enhance the destruction of platelets in ITP. Blockade of CD70 or CD11a are promising therapeutic approaches for ITP.
Journal of Clinical Immunology 05/2011; 31(4):632-42. · 3.08 Impact Factor
