A murine model for human immune thrombocytopenic purpura and comparative analysis of multiple gene expression in bone marrow and spleen

Homeostasis of platelet number in human and other mammals is well maintained for prevention of minor bleeding and for other im- munological functions, but the exact molecular mechanism responsible for immune thrombocytopenic purpura （ITP） has not been fully understood. In an effort to identify genetic factors involved in initiation of platelet production in response to bleeding injury or platelet destruction, we have successfully generated an animal model of human ITP via intraperitoneal injection of anti-platelet antibody into the Balb/c mouse. Platelet counts were dropped dramatically in animals that received antibody injection within 4 h, maintained at the mini- mum level for a period of 44 h, started to rebound after 48 h, and reached to the maximum at 144 h （6 days）. Final homeostasis reached at approximately 408 h （17 days）, following a minor cycle of platelet number fluctuation. Using semi-quantitative RT-PCR, we assessed and compared mRNA level of CD41, c-myb, c-mpl, caspase-3, caspase-9, GATA-1, and Bcl-xl in bone marrow and spleen. Alteration of mRNA expression was correlated with the change of platelet level, and an inverse relationship was found for expression of the genes be- tween bone marrow and spleen. No transcription was detectable for any of the seven genes in bone marrow at the time when platelet number reached the maximum （144 h）. In contrast, mRNA transcripts of the seven genes were found to be at the highest level in spleen tissue. This is the first study of simultaneous detection of multiple platelet related genes in a highly reproducible ITP animal model. Our results provided the supportive evidence that expression of the above seven genes are more related to negative regulation of platelet number in spleen tissue, at least in the model animals.

Study of establishing disease-syndrome combined with animal model for immune thrombocytopenic purpura without additional conditions

Objective:To explore the feasibility of establishing the disease-syndrome combined animal model for immune thrombocytopenic purpura(ITP)without additional conditions.Methods:Three batches of data related to the ITP model mice obtained by replication at different time were analyzed,and whether the APS-injected model mice replicated through the passive immune modeling method could simulate the pathogenesis and clinical characteristics of human ITP was evaluated according to the differentiation criteria for diseasesyndrome combined model.Results:The APS-injected replicated ITP model mice possessed the following traits:(1)Compared with the normal group,the platelet count was significantly decreased,and coagulation time was significantly increased in the model group(P<.01).(2)Compared with the normal group,the medullary thrombocytogenous megakaryocytes were significantly decreased(P<.05,.01,.001).(3)The APS-injected sites and other parts of the model mice had spontaneous hemorrhage.(4)Behavioral changing signs were observed 1 week after the modeling(i.e.low activity,delayed activity,poor appetite,skin petechia/hemorrhage and spontaneous hemorrhage at the injected sites or other parts),and were getting more and more severe.Conclusion:According to the syndrome differentiation criteria for disease-syndrome combined model of ITP,the APS-injected animal model of ITP replicated through the passive immune modeling method without additional conditions possesses the characteristics of disease-syndrome combined model.It provides an ideal tool for the development of traditional Chinese medicine pharmacology experiment.

Laparoscopic splenectomy for immune thrombocytopenic purpura at a teaching institution

Background High anatomic location, fragility, and generous blood supply of the spleen makes laparoscopic splenectomy （LS） difficult to master, and few patients need splenectomy for benign disorders. The aim of this research was to assess operative outcomes and hematological results of a large series of patients treated with LS for chronic immune thrombocytopenic purpura （ITP） and to determine which clinical variables predict favorable hematological outcome.Methods LS was successfully performed for 154 patients with chronic ITP from September 1999 to April 2009 at the First Affiliated Hospital of Sun Yat-sen University. Operative outcomes were assessed retrospectively. Long-term follow-up data were obtained from outpatient medical records and phone interviews. Clinical and laboratory variables （including gender, age, disease duration before surgery, previous response to steroids, preoperative platelet count, and postoperative peak platelet count） were evaluated by univariate analysis to identify potential predictors of hematological outcome. Multivariate Logistic regression model was used to determine independent predictors of hematological outcome.Results One patient died from subphrenic abscess and postoperative sepsis. The overall major morbidity rate was 8.4%. None of the patients required a second surgery for complications. Of the 127 patients available for a mean follow-up of 43.6 months （range 9-114 months）, the overall initial response （i.e., at two months after LS） and long-term response to LS were achieved in 89.0% and 80.3%, respectively. Five patients （3.9%） developed pneumonia 3-35 months after LS. Univariate analysis showed a significant difference in mean age between responders （29.1 years） and nonresponders （38.8 years; P ＜0.05）. Patients who responded to steroid therapy had better hematological outcome than those who did not respond （P ＜0.05）. Compared to nonresponders, responders to LS had a significantly higher postoperative peak platelet count （404x109/L versus 213×109/L, P ＜0.001）. Multivariate Logistic regression analysis identified postoperative peak platelet count as the only independent predictor of favorable response to LS （P＜0.001）.Conclusiona LS is a safe and effective treatment for chronic ITP. Postoperative peak platelet count may serve as a major predictor of long-term response.

Supraclavicular lymph node tuberculosis presenting with immune thrombocytopenic purpura

Tuberculosis （TB） differs from many other infectious maladies in having particular social and geographic distributions. The disease was under control in developed nations and being brought under control in developing countries, as in China. TB has now been recognized as a public health threat and the incidence of TB is steadily rising. Though a lot of various hematological disorders have been described in TB, like anemia, leukocytosis and, the most frequently cited, pancytopenia, immune thrombocytopenic purpura （ITP） is extremely rare. When thrombocytopenia occurs in TB, it happens most commonly via non-immune pathways, as typically described in the context of pancytopenia that develops secondary to tuberculous granulomatous infiltration of the bone marrow, but a causal relationship between TB and immune thrombocvtonenia is extraordinarilv rare.

Evaluation of miR-21 and miR-150 expression in immune thrombocytopenic purpura pathogenesis： a case-control study

BACKGROUND： Immune thrombocytopenic purpnra （ITP） is a common autoimmune disorder diagnosed with thrombocytopenia and bleeding symptoms due to production of autoantibodies （Abs） against platelets. Nowadays, microRNAs are known as novel biomarkers for diagnosis of diseases. The aim of this study was to investigate the expression levels of miR-21 and miR-150 in ITP patients and determine the role of these miRNAs in ITP pathogenesis. MATERIALS and METHODS： Thirty newly diagnosed patients with acute ITP and 30 healthy subjects（ age and sex matched） as controls were enrolled in this study. The expression level ofmiR-21 and miR- 150 was investigated using Real-time-PCR. Comparison of demographic characteristics of the cases was done using independent t-test and chi-square test. Comparison of the expression level of miR-21 and miR-150 with the related parameters was done using independent t-test or Mann-Whitney and Kruskal-Wallis test, Spearman rho correlation coefficient was used to investigate the relationship between the expression of miR-21 and miR-150 with demographic characteristics. RESULTS： The expression of miR-21, 150 in the patients was not different compared with the control group in general. A significant relationship between the expression of miR-21 with hemoglobin, hematocrit and red blood cell hemoglobin concentration was observed. DISCUSSION： Expression of miR-21 and miR-150 is not associated with pathogenesis of acute ITP and can involve the synergistic role of other miRNAs. Investigation of miR-21 and miR-150 expression along with other miRNAs and cytokines can be helpful in diagnosis and pathogenesis of ITP.

Mechanism study of the effect of Ningxue Shengban decoction on regulating the ratio of Treg/Th17 cells and downstream inflammatory factors in immune thrombocytopenia model mice

Background:To explore the role and mechanism of T cell imbalance in the process of immune thrombocytopenic purpura(ITP)and the efficacy of the Ningxue Shengban decoction in treating this disease.Methods:Passive immune ITP mouse model was established by injecting CD41 monoclonal antibody into BALB/c mice.The mice were divided into different groups for intervention and drug administration for 9 days.The therapeutic effects(blood cell count,bone marrow morphology)were observed.The changes in the number and proportion of regulatory T/Th17 cells in each group,as well as the expression of key transcription proteins and genes(Foxp3,RORγt)in mouse spleen,and the secretion of related inflammatory factors(interleukin-17,TGF-β,interleukin-21,interleukin-10)in serum were detected.Results:Ningxue Shengban decoction significantly increased the peripheral blood platelet count in ITP mice,improved bone marrow morphology,restored the imbalance of regulatory T/Th17 ratio,and exerted a positive regulatory effect on target proteins and downstream inflammatory factor secretion.Conclusion:Ningxue Shengban decoction may exert its therapeutic effect in treating ITP by regulating T cells and exerting immune regulatory function.

Eltrombopag-related renal vein thromboembolism in a patient with immune thrombocytopenia: A case report

BACKGROUND Eltrombopag is an orally administered thrombopoietin receptor agonist linked to a heightened risk of treatment-related thromboembolism.Both venous and arterial thromboses have been documented in the medical literature.CASE SUMMARY In the absence of nephropathy,a 48-year-old patient receiving eltrombopag for immune thrombocytopenia(ITP)developed renal vein thrombosis and pulmonary embolism.The renal vein thrombus spontaneously resolved during subsequent anticoagulant treatment,restoring venous circulation.CONCLUSION A rapid upsurge in platelets,rather than their absolute number,may trigger thrombotic events in this setting.For patients at high thrombotic risk,individualized eltrombopag dosing and vigilance in platelet monitoring are perhaps needed during treatment of ITP.