[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.

[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.

[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.

[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.

[Quantity and function of T follicular helper cells in the bone marrow of patients with immune thrombocytopenia].

This study was purposed to detect the quantity and function of bone marrow (BM) T follicular helper (Tfh) cells of patients with immune thrombocytopenia, and to explore the role of Tfh cells in the pathogenesis of ITP. Twenty-one newly diagnosed ITP patients, twenty ITP patients in recovery stage and eighteen normal controls were enrolled in this study. The percentages of Tfh cells, Tfh-related molecules ICOS, CD40L, IL-21 in BM were detected by flow cytometry (FCM), and the mRNA expression of BCL-6 in BMMNC was determined by semi-quantitive RT-PCR. Correlation of Tfh cell level with the disease severity of ITP patients was analysed. The results showed that the ratio of CD4(+)CXCR5(+)/CD4(+) cells in newly diagnosed ITP patients [(5.532 ± 2.599)%] was significantly higher than that in ITP patients with recovery stage [(4.064 ± 2.026)%] and controls [(4.048 ± 1.413)%] (P < 0.05). The ratio of CD4(+)CXCR5(+)ICOS(+)/CD4(+) CXCR5(+) cells in newly diagnosed ITP patients [(14.586 ± 8.561)%] was higher than that in recovery stage ITP patients [(12.884 ± 10.161)%] and controls [(7.487 ± 5.176)%]. The differences be-tween newly diagnosed ITP patients and controls were statistically significant (P < 0.05). The ratio of CD4(+)CXCR5(+) CD40L(+)/CD4(+) CXCR5(+) cells in newly diagnosed ITP patients [(15.309 ± 10.756)%] and in ITP patients with recovery stage [(18.242 ± 12.243)%] were significantly higher than that in controls [(8.618 ± 5.719) %] (P < 0.05). The ratio of intracytoplasm CD4(+) CXCR5(+) IL-21(+)/CD4(+)CXCR5(+) cells in newly diagnosed ITP patients [(58.560 ± 26.285)%] and in ITP patients with recovery stage [(57.035 ± 30.936)%] were significantly higher than that in controls [(36.289 ± 24.868)%] (P < 0.05). The relative expression levels of BCL-6 mRNA in BMMNC of three groups were (1.407 ± 0.264), (1.149 ± 0.217) and (0.846 ± 0.157), respectively. The differences between 3 groups were significant(P < 0.05). It is concluded that the quantity and function of Tfh cells in ITP patients increase, which may play an important role in the pathogenesis of ITP.

Elevated TIM3+ hematopoietic stem cells in untreated myelodysplastic syndrome displayed aberrant differentiation, overproliferation and decreased apoptosis.

TIM3, as a negative regulator of anti-tumor immunity, is highly expressed on LSCs, but not on normal HSCs. TIM3 on HSCs in MDS patients has not been clarified. Here, both the percentage of TIM3 on HSCs and the MFI of TIM3+ HSCs were higher in untreated MDS than control and were closed to AML, and excessive TIM3+ HSCs was closely related to clinical parameters: WPSS score, karyotype analysis, morphologic blasts, the number of cytopenia involving hematopoietic lineages, anemia and granulocytopenia. TIM3+ HSCs expressed lower CD11b, TpoR, EpoR, G-CSFR and Annexin V, and higher CD71 and GATA2. TIM3+ HSCs displayed aberrant differentiation, overproliferation and decreased apoptosis. TIM3 might be a promising marker for identifying malignant clone cells in MDS and a candidate for targeted therapy.

[Expression and clinical significance of miR-21 in diffuse large B cell lymphoma].

This study was aimed to investigate the expression of microRNA-21 and its correlation with PTEN in diffuse large B cell lymphoma (DLBCL) paraffin-embedded tissues, and evaluate its potential relevance with clinical characteristics. The expression levels of miR-21 in 26 primary DLBCL and 10 normal lymph node tissue specimens were examined by real-time polymerase chain reaction. The expression of PTEN was detected by immunohistochemical staining. The results indicated that the expression of miR-21 was significantly higher in tumor tissues [6.586(1.10,38.22)] than that in normal tissues [0.791 (0.35,2.87)] (P < 0.05). Among 26 patients with DLBCL the expression of PTEN protein was positive in 6 patients (23%), and was negative in 20 patients (77%). In patients with DLBCL, the expression level of miR-21 was negatively correlated with the level of PTEN protein. The high expression of miR-21 was positively correlated with the level of serum LDH. The expression level of miR-21 in patients with Ann Arbor III-IV stage was obviously higher than that of patients with Ann Arbor I-II stage, but did not correlate with the subtype of patients in clinic (P > 0.05). It is concluded that the expression of miR-21 is high in DLBCL and its overexpression may be related with poor prognosis of DLCBL. These findings suggest that PTEN is possibly one of the targets of miR-21 in DLBCL.

[Study on the dendritic cell subsets in peripheral blood and its relationship with the expressions of Gata-3 and T-bet in lymphocytes of patients with immune thrombocytopenia].

OBJECTIVE: To explore the relationship between the dendritic cell (DC) subsets and abnormal expression of transcription factors Gata-3 and T-bet in patients with immune thrombocytopenia (ITP). METHODS: The plasmacytoid DC (pDC) and myeloid DC (mDC) of 33 ITP (16 untreated, 17 remitted) patients and 12 healthy controls were analyzed by flow cytometry (FCM) . The expressions of Gata-3 mRNA and T-bet mRNA in peripheral blood mononuclear cell (PBMNC) were detected by reverse transcription-polymerase chain reaction (RT-PCR) .The levels of interleukin-4 (IL-4) and interferon-gamma (IFN-γ) were measured by FCM in 33 ITP patients and 12 healthy controls. RESULTS: The percentage of pDC in PBMNC was 0.49% ± 0.18% in untreated and it was higher than that in remitted ITP patients (0.27% ± 0.17%) and in controls (0.32% ± 0.13%) (both P < 0.05). The percentage of mDC in PBMNC was 0.23% ± 0.17% in untreated, which was lower than that in remitted ITP patients (0.33% ± 0.18)% and in controls (0.31% ± 0.11%), but no statistic difference in mDC expression existed among 3 groups (P > 0.05). pDC/mDC ratios was (3.15 ± 2.01) in untreated ITP patients and it was higher than that in remitted ITP patients (0.81 ± 0.32) and in controls (1.07 ± 0.44) (both P < 0.05). The relative mRNA expression levels of Gata-3 were 2775 ± 489, 1357 ± 307 and 652 ± 165 respectively. And the expression of Gata-3mRNA in untreated group was higher than that in remission group or healthy controls (both P < 0.05). The relative mRNA expression levels of T-bet were 782 ± 394, 583 ± 176 and 576 ± 120. No statistic difference in T-bet expression existed among 3 groups (P > 0.05). Gata-3mRNA/T-bet mRNA ratio was (4.13 ± 1.69 ) in untreated group and it was higher than that of remission group (2.45 ± 0.69) or controls (1.15 ± 0.27) (both P < 0.05). The level of IL-4 in the untreated group was 9.14% ± 4.34% and it was higher than that of remission group (4.78% ± 1.69%) or controls (4.86% ± 1.41%). The level of IFN-γ in the untreated group was lower than that of controls (P < 0.05). Significant positive correlations existed between Gata-3 and pDC/mDC ratio (r = 0.585, P < 0.01). Significant positive correlations existed between Gata-3 and IL-4 ( r = 0.463, P < 0.05). CONCLUSION: The mechanism of ITP may be due to a disorder of DC subsets and a high expression of Gata-3.

[Telomere length and gene expression of shelterin in CD3(+) T cell of severe aplastic anemia patients].

OBJECTIVE: To explore the changes in telomere length and gene expression of complex shelterin (composed of 6 core components: TRF1, TRF2, POT1, TIN2, TPP1 and RAP1) in severe aplastic anemia (SAA). METHODS: Bone marrow samples were obtained from 20 SAA patients and 10 normal controls. CD3(+)T cells were sorted by immunomagnetic separation. Telomere length was tested by Southern blot and the gene expressions of TRF1, TRF2, POT1, TIN2, TPP1 and RAP1 were detected by reverse transcription-PCR(RT-PCR). RESULTS: Telomeres of CD3(+)T cells were found significantly shorter in SAA untreated ((4.4 ± 1.1) kb, n = 9) and recovering groups((5.8 ± 1.0) kb, n = 11) than control group ((9.2 ± 3.3) kb, P < 0.05). Telomere length of CD3(+)T cells shortened with TH/S decreasing (r = 0.564, P = 0.029). The mRNA expression of POT1 decreased in untreated SAA patients (0.16(0.02-0.29)) and over-expressed in recovering patients (1.17(0.82-1.86), P < 0.05). The mRNA expression of RAP1 was significantly higher in untreated patients (4.14 (1.93-6.92)) than that in recovering group (0.87 (0.30-1.73) ) and controls (0.62 (0.45-4.07) , both P < 0.05). CONCLUSION: Changes in telomere length and shelterin gene expression occur in CD3(+)T cells of SAA patients and may be correlated with disease severity.

[Inhibitory effects of tacrolimus on effector T cells from patients with severe aplastic anemia].

OBJECTIVE: To explore the inhibitory effects of tacrolimus (FK506) on effector T cells in vitro and examine the relationship between effector T cells and clinical features in patients with severe aplastic anemia (SAA) to elucidate its immune mechanism. METHODS: The CD8(+) HLA-DR(+) cells, sorted by immunomagnetic separation from bone marrow mononuclear cells (BMMNC) of 16 SAA patients, were cultured in different concentrations of interleukin-2 (IL-2) alone or with FK506 for 72 hours. The proliferation effect was measured with methyl thiazolyl tetrazolium (MTT) method. The T lymphocytes were sorted from the SAA patients by lymphocyte separation medium and cultured alone or with IL-2 or with FK506 or FK506 plus cyclosporin A (CsA) for 18 hours. The expression of tumor necrosis factor-ß (TNF-ß) in CD8(+) HLA-DR(+) T cells was analyzed by flow cytometry. The relationship between the expression of TNF-ß and the clinical data, including percentages of reticulocyte and lymphocytes in peripheral blood cell count and ratio of CD4(+) T cells and CD8(+)T cells, was also analyzed. RESULTS: At the concentration of IL-2 greater than or equal to 20 U/ml, the cell proliferation (A values, 0.538 ± 0.142) were significantly higher than that in the blank culture hole (0.505 ± 0.153) (P < 0.05). The A values significantly decreased (0.386 ± 0.124) after the addition of FK506 (P < 0.05). Compared with control group, the expression of TNF-ß was significantly higher in IL-2 group (73.36% ± 16.73% vs 66.61% ± 16.20%, P < 0.05), significantly lower in FK506 and FK506 plus CsA groups (P < 0.05). No significant differences existed between the FK506 and FK506 plus CsA groups (47.78% ± 20.09% and 42.23% ± 21.35%, P > 0.05). The expression of TNF-ß in SAA was negatively correlated with the percentage of reticulocyte and the ratio of CD4(+) T cell and CD8(+) T cell, positively correlated with the percentage of lymphocyte in peripheral blood count (r = -0.86, -0.90, 0.77, all P < 0.05). CONCLUSIONS: IL-2 can enhance the proliferation and expression of TNF-ß of CD8(+)HLA-DR(+)T cells from SAA patients. Such an effect is inhibited by FK506. And FK506 and FK506 plus CsA have similar effects.

[Preliminary study on the quantity and function of T follicular helper cells in the cytopenic patients with positive BMMNC-Coombs test].

OBJECTIVE: To study the quantity and function of bone marrow (BM) T follicular helper (Tfh) cells of the cytopenia patients with positive bone marrow mononuclear cells (BMMNC)- Coombs test (also known as immuno-related pancytopenia, IRP), and explore the role of Tfh cells in the pathogenesis of IRP. METHODS: Forty- three untreated IRP patients, 47 recovered IRP patients and 25 healthy donors were enrolled in this study. The percentages of Tfh cells, Tfh-related molecules ICOS, CD40L, IL-21 and Bcl-6 in BM were investigated by flow cytometry and semiquantitive RT-PCR. RESULTS: The ratio of CD4⁺CXCR5⁺/CD4⁺ cells of untreated IRP patients [(28.79 ± 19.70)%] was significantly higher than that of recovered IRP patients [(21.15 ± 12.81)% ] and normal controls ([ 13.42 ± 6.72)% ](P<0.05). The ratio of CD4⁺CXCR5⁺ICOS⁺/CD4⁺CXCR5⁺ cells of untreated IRP patients [(5.05 ± 4.71)% ] was significantly higher than that of recovered IRP patients [(2.96 ± 2.89)% ] and normal controls [(2.99 ± 2.23)% ] (P<0.05). The ratio of CD4⁺CXCR5⁺CD40L⁺/CD4⁺CXCR5⁺ cells of untreated IRP patients [(5.87 ± 4.14)%] and recovered IRP patients [(6.52±5.47)%] were significantly higher than that of normal controls [(2.93 ± 2.92)%] (P<0.05). The ratio of intracytoplasmic CD4⁺CXCR5⁺IL-21⁺/CD4⁺CXCR5⁺ cells of untreated IRP patients [(8.20 ± 7.41)% ] and recovered IRP patients [(6.30 ± 6.03)% ] were significantly higher than that of normal controls [(3.43 ± 3.40)%] (P<0.05). The relative expressions of Bcl-6 mRNA in BMMNC were 0.625 ± 0.248, 0.485 ± 0.253, 0.306 ± 0.210 in three groups, respectively. The differences between untreated IRP patients, recovered IRP patients and normal controls were significant (P<0.05). CONCLUSION: There exists increased quantity and hyperfunction of Tfh cells in the IRP patients, they may play important role in the pathogenesis of IRP. Tfh cells and their related effector molecules could be a potential therapeutic target for the disease.

[Expression of microRNA-223 in lymphocytic leukemia cells and its action mechanism].

This study was aimed to investigate the expression level and mechanism of microRNA-223 and LMO2 in acute lymphoblastic leukemia (ALL) and chronic lymphocytic leukemia (CLL) cells and the mechanism. MicroRNA-223 mimics was transfected to increase the expression of MicroRNA-223 in the lymphocytes sorted by ficoll separation from the bone marrow mononuclear cells (BMMNC) of ALL and CLL patients. MicroRNA-223 inhibitor was transfected to decrease the expression of the MicroRNA-223 in the lymphocytes of normal controls. Then the expression of the MicroRNA-223 and LMO2 in transfected lymphocytes before and after cultivating for 72 hours were detected by RT-PCR, the apoptosis and cell cycle of these cells were measured by flow cytometery. The results indicated that before the transfection, the expression of MicroRNA-223 in ALL and CLL cells was (433.11 ± 144.88), which was significantly lower than that in the normal lymphocyte (949.59 ± 267.39); the expression of LMO2 was (807.10 ± 238.41), which was significantly higher than that in the normal lymphocytes (455.32 ± 176.83) (P < 0.05); after the transfection, the expression of MicroRNA-223 was (571.86 ± 142.00) in ALL and CLL cells, which was significantly higher than that before transfection (P < 0.05), but the expression of LMO2 was significantly lower than that before transfection (651.97 ± 230.12) (P < 0.05); in the normal control the expression of MicroRNA-223 obviously decreased (646.32 ± 172.93) (P < 0.05), the expression of LMO2 was significantly increased (541.27 ± 158.86.2) (P < 0.05). After transfection, the cell cycle G1/G2 phase and apoptosis changed in ALL and CLL cells. Before transfection the cell ratio in cell cycle G1/G2 phase was (94.75 ± 3.15)%, the cell ratio in S phase was (5.14 ± 3.12)%; after transfection the cell ratio in cell cycle G1/G2 phase was (97.03 ± 2.08)% and obviously increased (P < 0.05), the cell ratio in S phase was (2.97 ± 2.08)% and significantly decreased (P < 0.05). Before transfection the apoptosis rate was (54.47 ± 8.72)%, and obviously was higher than that after transfection (60.48 ± 8.81)%. And in the normal control, the cell ratio in G1/G2 phase was significantly higher than that after transfection [(96.73 ± 2.26)%, (94.55 ± 2.77)%, P < 0.05)], and the cell ratio in S phase was significantly increased [(3.25 ± 2.26)%, (5.45 ± 2.77)% (P < 0.05)]. The apoptotic rate in the ALL and CLL patients was significantly higher than that after the transfection [(54.47 ± 8.72)% vs (60.48 ± 8.81)%, respectively (P < 0.05)]. The apoptotic rate in the normal control was significantly lower than that after the transfection [(59.02 ± 10.20)%, (51.96 ± 10.20)%, respectively (P < 0.05)]. It is concluded that the expression of MicroRNA-223 decreases, and the expression of LMO2 increases in lymphocytic leukemia cells which leads to the lymphocytes over-proliferation and abnormal apoptosis, thus may be one of pathogenesis in lymphocytic leukemia.

[The mechanisms underlying bone marrow damage by iron overload in pancytopenic patients with positive BMMNC-Coombs test].

OBJECTIVE: To investigate the mechanisms underlying bone marrow damage by iron overload in pancytopenic patients with positive BMMNC-Coombs test (IRP). METHODS: Twenty-one iron overloading, 26 non-iron overloading IRP patients and 10 normal controls were enrolled in this study. The expressions of ROS, Bcl-2, Caspase-3 and apoptosis of BMMNC were analyzed by flow cytometry (FCM). Antioxidants were added to iron overloading IRP BMMNC, and then the changes of indices above were detected by FCM. The number and apoptosis of T lymphocytes of IRP patients were also detected. RESULTS: ROS and apoptosis of BMMNC, myelocytes, erythrocytes and stem cells of iron overloading IRP patients were significantly higher than that of non-iron overloading IRP ones and normal controls (P < 0.05). The expressions of Bcl-2 on BMMNC, erythrocytes and stem cells of iron overloading IRP patients were significantly lower than those of non-iron overloading IRP ones (P < 0.05). The levels of Caspase-3 on myelocytes, erythrocytes and stem cells of iron overloading IRP patients were significantly higher than those of non-iron overloading IRP ones and normal controls (P < 0.05). After treatment with antioxidants, the expressions of ROS, Caspase-3 and apoptosis of iron overloading IRP BMMNC significantly decreased, but opposite for Bcl-2. The percentages of CD4(+) lymphocytes [ ( 40.86 ± 8.74）%] and CD4(+)/CD8(+) (1.44 ± 0.36) in PB of iron overloading IRP patients were significantly higher than that of non-iron overloading IRP ones [(35.96 ± 7.03)% and 1.14 ± 0.37] and normal controls [(28.00 ± 6.73)% and 0.79 ± 0.21], respectively (P < 0.05), as opposite for CD8(+) lymphocytes (P < 0.05). The apoptosis of CD8(+) lymphocytes [(27.35 ± 10.76)%] and the ratio of CD8(+) apoptosis/CD4(+) apoptosis (2.51 ± 0.81) in BM of iron overloading IRP patients were significantly higher than those of non-iron overloading IRP ones [(15.47 ± 8.99)%] and normal controls (1.39 ± 0.47), respectively (P < 0.05). The apoptosis of erythrocytes and stem cells coated with auto-antibodies in BM of iron overloading IRP patients were significantly higher than those of non-iron overloading IRP and normal controls. CONCLUSION: Mechanisms underlying bone marrow damage by iron overload might be through the follows: ①The increased ROS induced by excessive iron deposition affected the expressions of Caspase-3 and Bcl-2, which caused more BMMNC apoptosis; ②The abnormal number and ratio of T lymphocytes caused by iron overload aggravated the abnormality of immunity of IRP; ③Iron overload may increase the damage to erythrocytes and stem cells coated with auto-antibodies.

[The long-term efficacy and safety of rituximab combined with cyclophosphamide in treatment of seven patients with refractory and recurrent autoimmune hemolytic anemia].

OBJECTIVE: To assess the efficacy and safety of monoclonal antibody rituximab combined with cyclophosphamide (CTX) in the treatment of refractory and recurrent autoimmune hemolytic anemia. METHODS: Seven cases with refractory and recurrent autoimmune hemolytic anemia (including 1 case of Evans syndrome) were recruited during January, 2007 to December, 2010. Treatment regimens were as follows: rituximab: 375 mg/m², 1 time/week, 2-6 courses; CTX:1 g, 1/10 d, 2-7 courses; combined with intravenous immunoglobulin (IVIG) 5 g, 1 time/week, given 1 day after rituximab administration. The efficacy and safety of this regimen were assessed during follow-up. RESULTS: All the patients showed good responses (7/7). Six patients achieved complete remission (6/7) and one achieved partial remission (1/7). Average follow-up time for the patients was 27 months. All patients remained in remission during the 12-month follow-up visits. Two patients showed elevated indirect bilirubin and increased reticulocyte counts within 24 months. One patient achieved complete remission after additional rituximab therapy, and another patient remained partial remission after cyclosporine therapy. At the time of 36-month follow-up visit, the patient relapsed and was retreated with 3 courses of rituximab combined with CTX and eventually achieved partial remission. All patients tolerated the treatment well with few mild side effects. CONCLUSIONS: Rituximab combined with CTX is effective and relatively safe in patients with refractory and recurrent autoimmune hemolytic anemia. Additional treatment to relapse patients about 12 - 24 months after drug withdrawal continues to be effective.

[TET2 and DLK1 gene expression and their clinical significance in bone marrow CD(3)(+) T cells of patients with myelodysplastic syndrome].

OBJECTIVE: To investigate the expression of TET2 and DLK1 mRNA in bone marrow CD(3)(+) T cells of patients with myelodysplastic syndrome (MDS) and their clinical significance and to explore the potential mechanism of abnormal cell-mediated immunity. METHODS: CD(3)(+) T cells were sorted by magnetic activated cell-sorting system. The expressions of TET2 and DLK1 mRNA in bone marrow CD(3)(+) T cells from 26 MDS patients and 16 healthy controls were detected by fluorescence quantitative PCR. RESULTS: The expression of TET2 mRNA in CD(3)(+) T cells was down-regulated in the MDS patients by (0.16 ± 0.15) fold compared with the controls (P < 0.05). The expression of TET2 mRNA in CD(3)(+) T cells of MDS patients was positively correlated with serum complement C(3) (r = 0.404, P < 0.05). The expression of DLK1 mRNA in CD(3)(+) T cells was up-regulated in the MDS patients by (1.61 ± 0.88) folds compared with the controls (P < 0.05). Grouped by the chromosomes, the patients with chromosome abnormalities presented significantly higher DLK1 mRNA level than those with normal chromosomes [(1.45 ± 0.44) folds, P < 0.05]. The expression of DLK1 mRNA in CD(3)(+) T cells of MDS patients was positively correlated with the proportion of bone marrow blasts (r = 0.343, P < 0.05). CONCLUSIONS: The mRNA expression of TET2 in CD(3)(+) T cells of MDS patients was decreased while the mRNA expression of DLK1 was increased, which might decline the immune surveillance function. The findings would be useful for exploring the mechanism of immune tolerance.

[Research of regulative factors on CD8(+)HLA-DR(+) effector T cells in severe aplastic anemia].

OBJECTIVE: To explore the regulative factors on CD8(+)HLA-DR(+) T cells in the patients with severe aplastic anemia (SAA) and examine the roles of these cells in the immunopathogenesis of SAA. METHODS: CD8(+)HLA-DR(+) T cells were sorted from bone marrow mononuclear cells of 13 SAA patients from July 2011 to March 2012 by magnetic activated cell sorting system and were divided into 3 groups: interleukin 2 (IL-2) group (0, 0.1, 1, 10, 100 and 1000 U/ml), cyclosporine A (CsA) group (addition of 400 ng/ml CsA in each IL-2-containing well),receptor antagonist group (addition of IL-2 receptor antagonist 8 µg/ml in each IL-2-containing well). Then cell proliferation rate was evaluated by MTT assay after a 72-hour culturing. Bone marrow mononuclear cells of the SAA patients were divided into CsA group, IL-2 group and control group and cultured for 18 hours and another 4 hours following the dosing of phorbol ester. The expression of tumor necrosis factor ß (TNF-ß) in CD8(+)HLA-DR(+) T cells was analyzed by flow cytometry. RESULTS: The cell proliferations of IL-2 wells at the concentrations of 10, 100 and 1000 U/L (0.36 ± 0.12, 0.41 ± 0.12, 0.46 ± 0.14) were significantly higher than those of the control wells (0.23 ± 0.11), CsA group (0.18 ± 0.05, 0.19 ± 0.00, 0.20 ± 0.04) and receptor antagonist group (0.18 ± 0.05, 0.17 ± 0.04, 0.18 ± 0.03, all P < 0.05). No statistic difference existed between CsA and receptor antagonist groups (P > 0.05). The expressions of TNF-ß of CD8(+)HLA-DR(+)T cells of the IL-2 group were higher than those of the control group (64% ± 25% vs 46% ± 22%) whereas the CsA group (27% ± 20%) were lower than those of the control group (both P < 0.05). CONCLUSIONS: IL-2 can significantly stimulate the proliferation of CD8(+)HLA-DR(+) T cells and accelerate the in vitro secretion of TNF-ß in SAA patients. The proliferation may be inhibited by CsA and receptor antagonist. And the expression of TNF-ß is suppressed significantly by CsA.

[STAT5 phosphorylation in CD34(+)CD38(-)CD123(+) bone marrow cells of the patients with myelodysplastic syndrome].

OBJECTIVE: To investigate the expressions of STAT5 phosphorylation in CD34(+)CD38(-)CD123(+) bone marrow cells of the patients with myelodysplastic syndromes (MDS), and then evaluate the level of activation of STAT5 associated with cell proliferation in MDS clone cells. METHODS: The bone marrow mononuclear cells (BMMNC) were extracted from 36 MDS patients and 14 normal controls. The mean fluorescence intensities (MFI) of phosphorylated STAT5(P-STAT5) in CD34(+)CD38(-)CD123(+) and CD34(+)CD38(-)CD123(-)cells, with or without the stimulation of 10 U/ml EPO, were examined by flow cytometry (FCM). RESULTS: Without stimulation, the P-STAT5 MFI in CD34(+)CD38(-)CD123(+) cells of low/high risk MDS patients was 113.71 ± 67.22/173.05 ± 102.78, which was significantly higher than that of CD34(+)CD38(-)CD123(-) cells (58.84 ± 27.51/68.99 ± 50.42, P < 0.01, P < 0.05) and the normal controls CD34(+)CD38(-)CD123(-) cells (63.06 ± 21.06, P < 0.05), there was no significant difference between the CD34(+)CD38(-)CD123(-) cells of MDS patients and the normal control CD34(+)CD38(-)CD123(-) cells; With the EPO stimulation, the P-STAT5 MFI in CD34(+)CD38(-)CD123(+) cells of low/high risk MDS patients was 144.04 ± 58.11/239.45 ± 152.05, which was significantly higher than that of CD34(+)CD38(-)CD123(-) cells (68.41 ± 25, 10/64.21 ± 23.43, P < 0.01) and the normal controls CD34(+)CD38(-)CD123(-) cells (75.21 ± 27.02, P < 0.01), there was no significant difference between the CD34(+)CD38(-)CD123(-) cells of MDS patients and the normal control CD34(+)CD38(-)CD123(-) cells; The P-STAT5 MFI in the CD34(+)CD38(-)CD123(+) cells of low/high risk MDS patients with or without EPO stimulation were 21.80/28.86, which was significantly higher than that of CD34(+)CD38(-)CD123(-) cells (7.42/5.50, P < 0.01, P < 0.05) and the normal controls CD34(+)CD38(-)CD123(-) cells (6.39, P < 0.05), there was no significant difference between the CD34(+)CD38(-)CD123(-) cells of MDS patients and the normal controls CD34(+)CD38(-)CD123(-) cells; There was no significant difference of P-STAT5 MFI with or without EPO stimulation and the increased P-STAT5 MFI between the CD34(+)CD38(-)CD123(+) cells of low and high risk MDS. CONCLUSION: STAT5 associated with cell proliferation was activated in CD34(+)CD38(-)CD123(+) bone marrow cells in MDS, which had more significant reactions to EPO than CD34(+)CD38(-)CD123(-) cells, indicating that CD34(+)CD38(-)CD123(+) bone marrow cells might be the real malignant MDS clone cells in MDS.