Effective Management of Polycythemia Vera With Ropeginterferon Alfa-2b Treatment.

Background: Polycythemia vera (PV) is a myeloproliferative neoplasm. Ropeginterferon alfa-2b is a new-generation polyethylene glycol-conjugated proline-interferon. It is approved for the treatment of PV at a starting dose of 100 µg (50 µg for patients receiving hydroxyurea (HU)) and dose titrations up to 500 µg by 50 µg increments. The study was aimed at assessing its efficacy and safety at a higher starting dose and simpler intra-patient dose escalation. Methods: Forty-nine patients with PV having HU intolerance from major hospitals in China were treated biweekly with an initial dose of 250 µg, followed by 350 µg and 500 µg thereafter if tolerated. Complete hematological response (CHR) was assessed every 12 weeks based on the European LeukemiaNet criteria. The primary endpoint was the CHR rate at week 24. The secondary endpoints included CHR rates at weeks 12, 36 and 52, changes of JAK2V617F allelic burden, time to first CHR, and safety assessments. Results: The CHR rates were 61.2%, 69.4% and 71.4% at weeks 24, 36, and 52, respectively. Mean allele burden of the driver mutation JAK2V617F declined from 58.5% at baseline to 30.1% at 52 weeks. Both CHR and JAK2V617F allele burden reduction showed consistent increases over the 52 weeks of the treatment. Twenty-nine patients (63.0%) achieved partial molecular response (PMR) and two achieved complete molecular response (CMR). The time to CHR was rapid and median time was 5.6 months according to central lab results. The CHRs were durable and median CHR duration time was not reached at week 52. Mean spleen index reduced from 55.6 cm2 at baseline to 50.2 cm2 at week 52. Adverse events (AEs) were mostly mild or moderate. Most common AEs were reversible alanine aminotransferase and aspartate aminotransferase increases, which were not associated with significant elevations in bilirubin levels or jaundice. There were no grade 4 or 5 AEs. Grade 3 AEs were reversible and manageable. Only one AE led to discontinuation. No incidence of thromboembolic events was observed. Conclusion: The 250-350-500 µg dosing regimen was well tolerated and effectively induced CHR and MR and managed spleen size increase. Our findings demonstrate that ropeginterferon alfa-2b at this dosing regimen can provide an effective management of PV and support using this dosing regimen as a treatment option.

[Expression and Significance of PD-1 and ICOS in Patients with Primary Immune Thrombocytopenia].

OBJECTIVE: To investigate the expression of programmed death receptor-1 (PD-1) and inducible costimulator (ICOS) on the surface of CD8+ T cells in peripheral blood of patients with primary immune thrombocytopenia (ITP), and explore the roles of PD-1 and ICOS in the occurrence and development of ITP. METHODS: A total of 28 ITP patients treated in Tianjin Medical University General Hospital from September to December 2020 were selected, including 13 patients with newly diagnosed ITP, 15 patients with chronic ITP, and 22 healthy volunteers were recruited as control group. Flow cytometry was used to detect the expression levels of PD-1 and ICOS, and evaluate their correlation with clinical indicators. RESULTS: The percentage of CD8 + T cells in ITP patients of chronic group was higher than that of the newly diagnosed group and the control group (P<0.05). The expression level of PD-1 on CD8+ T cells in ITP patients of newly diagnosed group and chronic group were significantly lower than that of the control group (P<0.05), while the expression level of ICOS were significantly higher (P<0.05). In ITP patients, PD-1 was negatively correlated with platelet count (r=-0.4942, P<0.01), but positively with ICOS (r=0.4342). PD-1 and ICOS were both negatively correlated with lymphocyte count (rPD-1=-0.4374; rICOS=-0.4492). CONCLUSION: In ITP patients, the unbalanced expression of PD-1 and ICOS may interfere with the immune homeostasis of the body, which can be used as a therapeutic target for ITP patients.

[Inhibitory Effect of Ascorbic Acid on Myelodysplastic Syndrome Cells and Its Mechanism].

OBJECTIVE: To investigate the inhibitory effect of ascorbic acid single or combination of decitabine on tumor cells of myelodysplastic syndrome (MDS) and explore its related mechanism. METHODS: The human MDS cell lines SKM-1 and MUTZ-1 were treated with different concentrations of ascorbic acid, and the cell proliferation activity was detected by the CCK-8 assay. The reactive oxygen species (ROS) level, labile iron pool (LIP), cell cycle, and apoptosis of SKM-1 and MUTZ-1 cells were detected by flow cytometry. The control group, ascorbic acid monotherapy group, decitabine monotherapy group, and combination group of ascorbic acid and decitabine were set up, the cell proliferation activity and apoptosis were detected in each group. RESULTS: High-dose ascorbic acid could reduce the cell proliferation activity of SKM-1 (R=0.886, p=0.000) and MUTZ-1 (R=0.880, p=0.000). With the increase of ascorbic acid concentration, the ROS level in SKM-1 and MUTZ-1 cells increased (r=0.816, r=0.942), the proportion of cells stagnation in G2 phase increased (r=0.970, p=0.000; r=0.962, p=0.000), the proportion of surviving cells decreased (r=-0.966, p=0.000; r=-0.952, p=0.000), and the apoptosis cells significantly increased (r=0.966, p=0.000; r=0.958, p=0.000). Nevertheless, the level of LIP showed no significant changes. After the combined application of ascorbic acid and decitabine, MDS tumor cells showed decreased proliferative activity and increased apoptosis compared with single-agent ascorbic acid and decitabine group. CONCLUSION: High-dose ascorbic acid shows a cytotoxic effect on MDS tumor cells, inhibiting cell proliferation and increasing apoptosis. Ascorbic acid combined decitabine have a synergistic effect of anti-MDS tumor cells.

[Research Progress on Pathogenesis of Congenital Pure Red Cell Aplasia---Review].

Congenital pure red cell aplasia, also known as Diamond-Blackfan anemia (DBA), is a hereditary disease characterized by pure red cell aplasia and congenital malformation. Its main clinical features are anemia, dysplasia, and tumor susceptibility. Ribosomal protein (RP) gene mutation is the main pathogenesis of DBA. The most common type of gene mutation is RPS19 gene mutation. Heterozygous mutations in as many as 19 RP genes and other non-RP genes mutations have been identified in DBA. This review summarized briedfly the latest research advances in the pathogenesis of DBA.

[Expression and Significance of IL-9 and IL-6 in Patients with BCR-ABL- MPN].

OBJECTIVE: To investigate the expression of IL-9 and IL-6 in patients with BCR-ABL- bone marrow proli- ferative tumor (MPN), and to explore its role in the occurrence and development of MPN. METHODS: A total of 71 newly diagnosis MPN patients treated in Tianjin Medical University General Hospital from 2018 to 2019 were selected, including 32 patients with polycythemia vera (PV) and 22 patients with primary thrombocytosis (ET), and 17 patients with primary myelofibrosis (PMF). Then 58 patients who retestine after treatment were selected as therapy group，and 20 healthy volunteers were recruited as control group. ELISA was used to detect the expression level of IL-6 and IL-9 in bone marrow supernatant, and the relative expression level of IL-6 and IL-9 mRNA in BMMNC was detected by real-time PCR. The proportion of Th9 cells in peripheral blood were detected by flow cytometry (FCM). The expression level of IL-6 mRNA and IL-9 mRNA of BMMNC and clinical indicators were analyzed, and the correlation between JAK2 gene mutation load and IL-9 level was further analyzed. RESULT: The level of IL-6 in bone marrow supernatant and the expression of IL-6 mRNA in BMMNC were higher in the newly diagnosed group as compared with those in the treated group and the control group (P<0.001). The expression level of IL-9 in bone marrow supernatant and the expression of IL-9 mRNA in BMMNC were lower in the newly diagnosed group as compared with those in the treated group and the control group (P<0.05). The proportion of Th9 cells in peripheral blood was lower in the newly diagnosed group as compared with that in the treated group and the control group (P<0.001). The level of IL-6 in bone marrow supernatant and the expression of IL-6 mRNA in BMMNC in JAK2+ group were higher than those in JAK2- group (P<0.05). The expression level of IL-9 in bone marrow supernatant and the expression of IL-9 mRNA in BMMNC were lower in JAK2+ group as compared with those in JAK2- group (P<0.05). The expression of IL-6 and IL-9 in the patient group showed correlation with the number of lymphocytes (IL-6: r=-0.49, P<0.01; IL-9: r=0.53, P<0.001), and also related with Hb in PV patients (IL-6: r= 0.87, P<0.001; IL-9: r=-0.54, P<0.01), and platelets in ET patients (IL-6: r=0.64, P<0.05; IL-9: r=-0.46, P<0.05). CONCLUSION: The increased expression of IL-6 in MPN and hyperfunction may promote the progression of BCR-ABL- MPN disease. The expression of IL-9 in MPN decreases, and it negatively correlates with the mutation load of JAK2 gene, which may be related with the decrease of tumor environmental antitumor immune effect.

Advances in the role of helper T cells in autoimmune diseases.

Autoimmune diseases are primary immune diseases in which autoreactive antibodies or sensitized lymphocytes destroy and damage tissue and cellular components, resulting in tissue damage and organ dysfunction. Helper T cells may be involved in the pathogenesis of autoimmune diseases under certain conditions. This review summarizes recent research on the role of helper T cells in autoimmune diseases from two aspects, helper T cell-mediated production of autoantibodies by B cells and helper T cell-induced activation of abnormal lymphocytes, and provides ideas for the treatment of autoimmune diseases. The abnormal expression of helper T cells promotes the differentiation of B cells that produce autoantibodies, which leads to the development of different diseases. Among them, abnormal expression of Th2 cells and T follicular helper cells is more likely to cause antibody-mediated autoimmune diseases. In addition, abnormal activation of helper T cells also mediates autoimmune diseases through the production of abnormal cytokines and chemokines. Helper T cells play an essential role in the pathogenesis of autoimmune diseases, and a full understanding of their role in autoimmune diseases is helpful for providing ideas for the treatment of autoimmune diseases.

[Inhibitory Effect of Decitabine-inhibeting Methylation of SHP-1 Gene on Proliferation and Apoptosis of MDS Cell Line Skm-1].

OBJECTIVE: To investigate the phenotype and molecular mechanism of DCA on MDS cell model, and to study the response of chemotherapeutic medicines to MDS cells through multiple dimensions, such as cell proliferation, invasion, migration and apoptosis, thus revealing the molecular mechanism of DCA treatment of MDS and its relationship with SHP-1 gene methylation. METHODS: MTT assay was used to determine the survival rate of MDS cells after treated by different concentrations of DCA. The effect of DCA on the invasion and migration of MDS cells was detected by Transwell assay method. Apoplexin V-FITCPI was used to detect apoptosis, the MDS treatment on the mechanism of DCA was investigated by Western blot and Real-time PCR experiment. RESULTS: According to the experiment, it was found that tumor proliferation could be inhibited when MDS skm-1 cells was treated by DCA, and the absorbance was lower and the inhibitory effect was more obvious in the 2.0, 5.0 µmol/L DCA group than in the 0.5 µmol/L DCA group and the negative control group. Compared with the control group, the number of MDS skm-1 cells crossing through the transwell upper chamber was significantly decreased after DCA application. After treated with 0.5, 2.0 and 5.0 µmol/L DCA, the apoptosis rate of MDS cells was 4.54%, 9.31% and 16.58% respectively, while the apoptosis rate of the control group was 3.20%, which shows the apoptosis rate increased significantly with the concentration of DCA. After treatment of MDS cell lines with different concentration of DCA, the methylation status of SHP-1 gene was decreased with the increase of drug concentration, the expression of SHP-1 was increased, the expression of STAT3 was decreased and the level of phosphorylation was decreased. CONCLUSION: By analyzing the phenotypic response of DCA treatment on MDS cells, it was found that interfere with MDS can be performed by inhibiting proliferation, metastasis, and inducing apoptosis in a dose-dependent way. It revealed that the molecular mechanism by DCA treatment can improve the methylation of SHP-1 gene and inhibit the expression of p-STAT3.

[Relationship of Peripheral Blood IL-37 Expression with T Lymphocytes Subsets and NK Cells in Patients with Primary Immune Thrombocytopenia].

OBJECTIVE: To study the correlation of IL-37 with T lymphocytes subsets and NK cells in ITP patients, and to explore its possible mechanisms involved in the pathogenesis of ITP. METHODS: Forty-five patients with newly diagnosed ITP(newly diagnosed group), 32 patients of complete remission (remission group) and 22 healthy persons(control group) were selected. The serum level of IL-37 in 3 groups was determined by enzyme linked immunosorbent assay (ELISA). The mRNA expression of IL-37, IL-17 and IL-18 in peripheral blood mononuclear cells（PBMNC） in 3 groups was measured by real-time fluorescence quantitative polymerase chain reaction (PCR). The number of IL-18Rα+CD4+ T cells and Tim-3+NK cells in the peripheral blood in 3 groups was detected by flow cytometry (FCM). RESULTS: The serum level of IL-37 in the peripheral blood of ITP patients in the newly diagnosed group was significantly higher than that in the control group and the remission group(P＜0.01) . The expression level of IL-37 in PBMNC of the ITP patients in newly diagnosed group was higher than that in the control group and the remission group(P＜0. 05). The expression level of IL-17 and IL-18 in PBMNC of the ITP patients in newly diagnosed group was higher than that in the control group and the remission group(P＜0. 01); the expression of IL-18Rα in CD4+ T cells in newly diagnosed group was significantly higher than that in both the control and the remission group(P＜0.01).The expression of Tim-3 in NK cells in ITP patients was significantly lower than that in the control group (P＜0. 01). In ITP patients, the serum IL-37 level and IL-18Rα+CD4+T cells ratio both negatively correlated with Plt count (r=-0.58, r=-0.48) moreo-ver the serum IL-37 level also negatively correlated with amount of CD4+ T cells and NK cells (r=-0.29, r=-0.28), but positively correlated with amount of CD8+ T cells (r=0.329). CONCLUSION: The IL-37 and its receptors may play an immunoregulatory role in CD4+ T cells and NK cells, the IL-37 may be a therapeutic target for ITP patients.

[Number and Function of Myeloid-Derived Suppressor Cells in Patients with Adult Primary Immune Thrombocytopenia].

OBJECTIVE: To analyze the number of myeloid-derived suppressor cells(MDSC) and the level of prostaglandin E2(PGE2) in the bone marrow of adult ITP patients, and to explore their possible mechanisms involved in the pathogenesis of this disease. METHODS: Twenty-five patients of newly diagnosed ITP, 25 patients of complete remission group and 15 patients of control group were selected. The number of MDSC in the bone marrow between 3 groups was detect by flow cytometry (FCM). The serum level of prostaglandin E2 (PGE2) in 3 groups was determined by enzyme linked immunosorbent assay (ELISA). The relative expression of IFN-γ mRNA in bone marrow mononuclear cells was measured by real time fluorescence quantitative polymerase chain reaction (RT-qPCR) in each groups. RESULTS: The number of MDSC in the complete remission group was significantly higher than that in the control group (P<0.05); the number of MDSC in the newly diagnosed group was higher than that in the control group; the number of MDSC in the complete remission group was higher than that in the newly diagnosed group. The serum level of PGE2 in bone marrow of ITP patients in the newly diagnosed group was higher than that of the control group（P<0.05）. The serum level of PGE2 in the bone marrow of ITP patients of the complete remission group was higher than that of the control group (P<0.05）. The level of PGE2 in bone marrow serum of ITP patients of the newly diagnosed group was lower than that in the complete remission group(P<0.05）. The relative expression level of IFN-gamma in bone marrow mononuclear cells of the ITP patients in newly diagnosed group was higher than that in the control group and the complete remission group（P<0.001）. The relative quantification (RQ) of IFN-γ in bone marrow mononuclear cells was 2.60 between the newly diagnosed group and the complete remission group. CONCLUSION: When adult ITP disease is remitted, the number of MDSC rises and correlates with the therapeutic response and PGE2 level in the bone marrow.

Oral arsenic plus retinoic acid versus intravenous arsenic plus retinoic acid for non-high-risk acute promyelocytic leukaemia: a non-inferiority, randomised phase 3 trial.

BACKGROUND: Intravenous arsenic trioxide plus all-trans retinoic acid (ATRA) without chemotherapy is the standard of care for non-high-risk acute promyelocytic leukaemia (white blood cell count ≤10 × 109 per L), resulting in cure in more than 95% of cases. However, a pilot study of treatment with oral arsenic realgar-Indigo naturalis formula (RIF) plus ATRA without chemotherapy, which has a more convenient route of administration than the standard intravenous regimen, showed high efficacy. In this study, we compare an oral RIF plus ATRA treatment regimen with the standard intravenous arsenic trioxide plus ATRA treatment regimen in patients with non-high-risk acute promyelocytic leukaemia. METHODS: We did a multicentre, non-inferiority, open-label, randomised, controlled phase 3 trial at 14 centres in China. Patients aged 18-70 years with newly diagnosed (within 7 days) non-high-risk acute promyelocytic leukaemia, and a WHO performance status of 2 or less were eligible. Patients were randomly assigned (2:1) to receive treatment with RIF-ATRA or arsenic trioxide-ATRA as the induction and consolidation therapy. Randomisation was done centrally with permuted blocks and stratification according to trial centre and was implemented through an interactive web response system. RIF (60 mg/kg bodyweight daily in an oral divided dose) or arsenic trioxide (0·15 mg/kg daily in an intravenous dose) and ATRA (25 mg/m2 daily in an oral divided dose) were used until complete remission was achieved. The home-based consolidation therapy was RIF (60 mg/kg daily in an oral divided dose) or intravenous arsenic trioxide (0·15 mg/kg daily in an intravenous dose) in a 4-week on 4-week off regimen for four cycles and ATRA (25 mg/m2 daily in an oral divided dose) in a 2-week on 2-week off regimen for seven cycles. Patients and treating physicians were not masked to treatment allocation. The primary outcome was event-free survival at 2 years. A non-inferiority margin of -10% was used to assess non-inferiority. Primary analyses were done in a modified intention-to-treat population of all patients who received at least one dose of their assigned treatment and the per-protocol population. This study was registered with the Chinese Clinical Trial Registry (ChiCTR-TRC-13004054), and the trial is complete. FINDINGS: Between Feb 13, 2014, and Aug 31, 2015, 109 patients were enrolled and assigned to RIF-ATRA (n=72) or arsenic trioxide-ATRA (n=37). Three patients in the RIF-ATRA and one in the arsenic trioxide-ATRA did not receive their assigned treatment. After a median follow-up of 32 months (IQR 27-36), 67 (97%) of 69 patients in the RIF-ATRA group and 34 (94%) of 36 in the arsenic trioxide-ATRA group had achieved 2-year event-free survival in the modified intention-to-treat population. The percentage difference in event-free survival was 2·7% (95% CI, -5·8 to 11·1). The lower limit of the 95% CI for the difference in event-free survival was greater than the -10% non-inferiority margin, confirming non-inferiority (p=0·0017). Non-inferiority was also confirmed in the per-protocol population. During induction therapy, grade 3-4 hepatic toxic effects (ie, increased liver aspartate aminotransferase or alanine transaminase concentrations) were reported in six (9%) of 69 patients in the RIF-ATRA group versus five (14%) of 36 patients in the arsenic trioxide-ATRA group; grade 3-4 infection was reported in 15 (23%) of 64 versus 15 (42%) of 36 patients. Two patients in the arsenic trioxide-ATRA group died during induction therapy (one from haemorrhage and one from thrombocytopenia). INTERPRETATION: Oral RIF plus ATRA is not inferior to intravenous arsenic trioxide plus ATRA for the treatment of patients with non-high-risk acute promyelocytic leukaemia. This study suggests that a completely oral, chemotherapy-free model might be an alternative to the standard intravenous treatment for patients with non-high-risk acute promyelocytic leukaemia. FUNDING: Foundation for innovative research group of the National Natural Science Foundation of China, the Beijing Municipal Science and Technology Commission, the National Key R&D Program of China, and the National Natural Science Foundation of China.

[Latest Research Advance of Myeloproliferative Diseases Related Genes-Review].

JAK2, MPL and CALR gene mutations play an important role in the onset of myeloproliferative disease(MPD). The latest researches show that the difference of ATP binding ability between the wild type JAK2 protein and mutated JAK2 protein can help us understand the pathogenesis of the MPD further, and the clinical manifestation is related to the mutation burden of the JAK2. In some ET and PMF patients, research find the expression of MPL mutation, which can affects the progress of the disease by collaborating with the JAK2 mutation. CALR mutation is a gene related with the MPD that has been found recently. The pathogenesis of the CALR is similar to that of the JAK2, while there are some features in clinical manifestation comparing with the other mutations.

[Subtype and Functional Biomarker Changes of NK Cells in Peripheral Blood of Patients with Myelodysplastic Syndrome].

OBJECTIVE: To analyze the subtype and functional biomarker expression changes of natural kill cells(NK) in peripheral blood of patients with myelodysplastic syndrome(MDS) and normal people, so as to evaluate the relationships between these changes and hematopoietic functions and to explore the role of NK cells in the pathogenesis of MDS. METHODS: The quantity of NK cells and the expression of biomarkers(NKp30,NKp46,NKG2A) on NK cells were detected by flow cytometry in 35 MDS patients from 2015 to 2016 in our hospital and 34 normal controls. The correlation between these changes and hematopoietic functions, including the percentages of neutrophil(ANC), hemoglobin in peripheral blood and the hematopoietic function in bone marrow(CD34+%) were evaluated. RESULTS: The percentage and quantity of NK cells and CD56dim NK cells in MDS patients were significantly lower than those in normal controls(P<0.05); the percentage of CD56bright NK cells was higher than that in controls. The percentage of CD56dim NK cells in NK cells of MDS patients was significantly lower than that of controls; the percentage of CD56bright NK cells in NK cells of MDS patients was significantly higher than that of controls. The expression of NKp30 and NKp46 of MDS patients was significantly lower than that of controls. In MDS group, the percentage of NK cells and CD56dim NK cells of peripheral blood lymphocytes in high risk MDS group was significantly lower than that in low risk MDS group. The percentage of NK and CD56dim NK cells negatively correlated with that of CD34+% in bone marrow, but positively correlated with ANC and Hb. The CD34+% in bone marrow negatively correlated with expression of NKp46, but positively correlated with expression of NKG2A. CONCLUSION: The decrease of NK number and function may cause the immune surveillance and lead to disease progression.

[Prophylaxis of Bortezomib-Induced Peripheral Neuropathy in Patients with Multiple Myeloma by High-Dose Intravenous Mecobalamin].

OBJECTIVE: To evaluate the efficacy and safety of high-dose intravenous mecobalamin (HDIME) for the treatment of bortezomib-induced peripheral neuropathy(BIPN) in the patients with multiple myeloma (MM). METHODS: A total of 65 newly diagonsed patients with multiple myeloma receiving bortezomib in Tianjin Medical University General Hospital were enrolled in this single-centre randomized clinical trial from July 2012 to May 2016. Out of 65 patients 38 in control group received bortezomib-based chemotherapy and 27 patients in HDIME group received the additional high-dose intravenous mecobalamin. RESULTS: The incidence of BIPN in HDIME group was lower than that in control group(29.63% vs 55.26%, χ2=4.197,P<0.05). Whether the BIPN rate of Grade 2 or 3 and above in HDIME group significantly decreased as compared with control group(18.52% vs 47.37%,χ2=5.746,P<0.05) (3.71% vs 21.05%, χ2=3.983,P<0.05). The BIPN rate of less than 5 cycles of bortezomib was not significantly different between HDIME and control groups(χ2=2.714,P>0.05). Overall effective rate of HDIME group and control group was 77.78% and 73.68%(P>0.05) respectively. Neither PFS nor OS was significantly different between HDIME group and control group(P>0.05). Treatment-related toxicity was only mild rash in 1 case. No other side-effects including nausea, abdominal pain, and hypotension occurred. CONCLUSION: HDIME has a good efficacy for the prophylaxis BIPN and and without serious side effects.

[Single Nucleotide Polymorphism of Mitochondrial DNA D-LOOP Region in Peripheral Blood Lymphocytes of Immuno-related Pancytopenia Patients].

OBJECTIVE: To explore the single nucleotide polymorphism(SNP) of mitochondrial DNA (mtDNA) D-LOOP region in peripheral blood lymphocytes of immuno-related pancytopenia (IRP) patients and its correlation with immune parameters. METHODS: The D-LOOP region in mitochondrial DNA of lymphocytes in peripheral blood mononuclear cells from 43 patients with untreated IRP was detected by polymerase chain reaction(PCR). The PCR products were sequenced by the pros and cons direct sequencing methods. The sequencing results were compared with the revised Cambridge reference sequence (rCRS) and the Polymorphic Sites of Human Mitochondrial Genome Database. RESULTS: Among total of 110 variant positions of D-LOOP region in 43 patients, 62 was SNP sites and 48 was mutation sites, of which 14 were the new mutation sites not yet registered in the database, 516 base variations were observed at 110 positions, the most common variations were base substitutions, among them T/C and A/G was 184/410 and 113/410 respectively. In the 110 variant positions, the high frequency variation sites were 73 and 263 for 43/43,311 for 32/43,310 and 16 224 for 27/43,16 519 for 25/43, 489 and 16 362 for 24/43. By the analysis of mitochondrial DNA D-LOOP polymorphism and related clinical immunology indicators of the patient's lymphocytes, it was found that D-loop in adult patients (age≥ 18 years old) significantly correlated with CD15 IgM, GLYCoA+ Cells IgM, CD34+ CellsIgG, CD34+ Cells IgM correlation. CONCLUSION: The high frequency of polymorphism exists in mitochondrial DNA D-loop region of lymphocytes in IRPA patients, and was significantly correlates with the autoantibodies in bone marrow mononuclear cells in adult patients, which may be associated with the IRP occurrence.

[Expression and Significance of HOXA9 in Patients with Myelodysplastic Syndromes].

OBJECTIVE: To investigate the expression pattern of HOXA9 in myelodysplastic syndrome (MDS) patients and its relation with clinical characteristics and treatment response. METHODS: The mRNA and protein expression levels of HOXA9 in bone marrow cells from 33 cases of MDS, 12 cases of AML, 20 cases of ITP and 18 normal controls were detected by real-time guautitative PCR(RT-PCR) and flow cytometry, respectively. RESULTS: The percentage of HOXA9(+)/CD34(+) and HOXA9(+)/CD34(+)CD38(-) in MDS patients were significantly higher than that in control group (P<0.05), and the mRNA and protein expression of HOXA9 in MDS patients had a similar trend. The percentages of HOXA9(+)/CD34(+) and HOXA9(+)/CD34(+)CD38(-) before decitabine treatment were (50.64±27.59)% and (55.67±28.57)% respectively, which were both higher than those in control group (P<0.05). After decitabine treatment, expression of HOXA9 significantly decreased (P<0.05). CONCLUSION: HOXA9 is overexpressed in MDS patients and associated with several clinical characteristics. The detection of HOXA9 expression may have guide roles for diagnosis and treatment of MDS patients.

[Influence of Costimulatory Signaling Molecules on Immun Functons of B Lymphocytes in Patients with Immune Thrombocytopenia].

OBJECTIVE: To explore the effect of costimulatory signaling molecules (CD80, CD86) expression on the quantity and function of B lymphocytes in peripheral blood (PB) of the patients with immune thrombocytopenia (ITP). METHODS: A total of 55 ITP patients (30 cases were newly diagnosed and 25 cases were in remission), 25 healthy volunteers as controls were enrolled in this study. The levels of CD19(+)CD5(+), CD19(+)CD80(+), CD19(+)CD86(+), CD41a(+)IgG, CD41a(+)IgM and IgG, IgM in CD19(+)B cells were measured by flow cytometry (FCM). The correlation of CD19(+)B cells with clinical parameters of ITP patients was analyzed. RESULTS: The level of B1 (CD19(+)CD5(+)) of newly diagnosed ITP patients was significantly higher than that of remitted ITP patients and controls (P<0.05). The level of CD19(+)CD80(+) of newly diagnosed ITP patients was significantly higher than that of remitted ITP patients and controls (P<0.05). And the expression of IgG and IgM in CD19(+)B cells of newly diagnosed ITP patients was significantly higher than that of remitted ITP patients and controls (P<0.05). The levels of IgG and IgM in remitted ITP patients after treatment were significantly lower than that before treatment (P<0.05). The level differences of IgG and IgM before and after treatment in refractory ITP patients were not statistically significant (P>0.05). The expression of CD19(+)CD80(+) in newly diagnosed ITP patients positively correlated with the level of Th1 and Th1/Th2 (r=0.502, r=0.471, P<0.05). The expression of CD19(+)CD80(+) of newly diagnosed ITP patients positively correlated with the level of IgG and IgM in CD19(+)B cells (r=0.552, r=0.467, P<0.05), and negatively correlated with PB platelet count (r= -0.424, P<0.05). The levels of IgG and IgM in CD19(+)B cells of newly diagnosed ITP patients negati- vely correlated with PB platelet count (r=-0.658, r=-0.526, P<0.05). CONCLUSION: The enhacement of costimulatory signaling pathway of CD19(+)B cells in ITP patients results in the abnormal activation of B lymphocytes, thereby mediates the dysfunction of immune system and involves in the pathogenesis of ITP.

Expression and function of hematopoiesis-stimulating factor receptors on the GPI- and GPI+ hematopoietic stem cells of patients with paroxysmal nocturnal hemoglobinuria/aplastic anemia syndrome.

Paroxysmal nocturnal hemoglobinuria/aplastic anemia (PNH/AA) syndrome presents a markedly increased population of cells deficient in glycophosphatidylinositol (GPI- cells) and signs of bone marrow failure, which requires treatment with hematopoiesis-stimulating factors, such as granulocyte colony-stimulating factor (G-CSF) and stem cell factor (SCF). However, little is known about the effects of these stimulating factors on GPI- cells. In order to explore the effects of stimulating factors in PNH/AA, G-CSF receptor (CD114) and SCF receptor (CD117) expression levels on GPI+ and GPI- hematopoietic stem cells (HSCs) were measured by flow cytometry (FCM). The mean fluorescence intensity (MFI) values of signal transducer and activator of transcription 5 (STAT5) and phosphorylated (P)-STAT5 were measured in GPI+ and GPI- HSCs by FCM following stimulation with G-CSF or SCF in vitro. The expression levels of CD114 and CD117 on GPI- HSCs were significantly lower (P<0.01) than those on GPI+ HSCs in PNH/AA patients and normal controls. The MFI values of STAT5 in the GPI- and GPI+ HSCs of PNH/AA patients and normal controls were not significantly different. However, the MFI values of P-STAT5 in the GPI- HSCs of PNH/AA patients were significantly lower than those in the GPI+ HSCs of PNH/AA patients and normal controls prior to and following stimulation with G-CSF or SCF (P<0.01). The GPI- HSCs of PNH/AA patients responded poorly to stimulation by hematopoiesis-stimulating factors, which indicates that these factors can be used safely in patients with PNH/AA.

Effects of decitabine on megakaryocyte maturation in patients with myelodysplastic syndromes.

Thrombocytopenia is a common, often fatal complication experienced by patients with myelodysplastic syndromes (MDS). 5-aza-2'-deoxycytidine (decitabine) has been used to treat MDS patients with thrombocytopenia with a response rate of 45-50%. However, the mechanism of its effects on megakaryocytes remains unclear. In the present study, the effect of decitabine on megakaryocyte maturation was investigated. A total of 20 MDS patients diagnosed with thrombocytopenia were enrolled, including 16 refractory anemia with excess blasts (RAEB)-1 patients and 4 RAEB-2 patients], in addition to 20 leukemia patients that had achieved complete remission and 20 healthy donors. Overall, 65% of MDS patients exhibited a response to decitabine, with an increase in platelet count identified in 80% of patients. In the MDS group, the mean platelet count was significantly increased following one cycle of decitabine chemotherapy (36.85±24.54 vs. 84.90±61; P=0.001); however, no significant difference in megakaryocyte number was identified prior to and following treatment. Additionally, bone marrow mononuclear cells of the MDS patients were cultured in vitro with various concentrations of decitabine (0.0, 2.0, 2.5, 3.0 µM), and cluster of differentiation (CD)41 levels were examined via flow cytometry. The MDS and normal control groups exhibited the highest levels of CD41 expression following treatment with 2.0 µM decitabine (mean fluorescence intensity, 294.07±47.34 and 258.95±28.05, respectively). In conclusion, these results indicate that the DNA-hypomethylating agent, decitabine, may induce the differentiation and maturation of myelodysplastic megakaryocytes in MDS patients, even at low concentrations. Thus, the repeated administration of decitabine at lower doses in MDS patients may be useful in clinical practice, and may lead to the development of alternative treatments for other diseases of abnormal megakaryocyte differentiation, such as idiopathic thrombocytopenic purpura, however, future studies are required to investigate this.

[Bone Marrow Microenvironment and Myelodysplastic Syndromes--Review].

Myelodysplastic syndromes (MDS) are a group of bone marrow failure diseases. The bone marrow microenvironment consists of bone marrow stromal cells (BMSC), growth factors and cytokines. The BMSC supporting haemopoiesis include mesenchymal stem cells (MSC), osteoblasts, endothelial cells and macrophages, but the adipocytes play a role in the suppression of hematopoiesis. Recently more and more researches indicate that the abnormality of bone marrow microenvironment involves in the pathogenesis and progression of MDS. In this review the abnormality of MDS bone marrow microenvironment is summarized briefly.