Expression Changes of Hypoxia-Inducible Factor-1α in G-CSF Induced Hematopoietic Stem Cell Mobilization / 中国实验血液学杂志

OBJECTIVE@#To investigate the expression and its relative mechanism of hypoxia-inducible factor-1α(HIF-1α) in bone marrow(BM) of mice during G-CSF mobilization of hematopoietic stem cells (HSC) .@*METHODS@#Flow cytometry was used to detect the proportion of Lin-Sca-1+ c-kit+ (LSK) cells in peripheral blood of C57BL/6J mice before and after G-CSF mobilization. And the expression of HIF-1α and osteocalcin (OCN) mRNA and protein were detected by RQ-PCR and immunohistochemistry. The number of osteoblasts in bone marrow specimens of mice was counted under the microscope.@*RESULTS@#The proportion of LSK cells in peripheral blood began to increase at day 4 of G-CSF mobilization, and reached the peak at day 5, which was significantly higher than that of control group (P<0.05). There was no distinct difference in the expression of HIF-1α mRNA between bone marrow nucleated cells and osteoblasts of steady-state mice (P=0.073), while OCN mRNA was mainly expressed in osteoblasts, which was higher than that in bone marrow nucleated cells (P=0.034). After mobilization, the expression level of HIF-1α increased, but OCN decreased, and the number of endosteum osteoblasts decreased. The change of HIF-1α expression was later than that of OCN and was consistent with the proportion of LSK cells in peripheral blood.@*CONCLUSION@#The expression of HIF-1α in bone marrow was increased during the mobilization of HSC mediated by G-CSF, and one of the mechanisms may be related to the peripheral migration of HSC induced by osteoblasts inhibition.

Clinical Analysis of Bloodstream Infection after Hematopoietic Stem Cell Transplantation / 中国实验血液学杂志

OBJECTIVE@#To analyze the clinical characteristics of bloodstream infection (BSI) in patients treated by hematopoietic stem cell transplantation (HSCT).@*METHODS@#The clinical characteristics, distribution of pathogenic bacteria causing BSI and drug sensitivity of 910 patients treated by HSCT in our department from January 2013 to June 2020 were retrospectively analyzed.@*RESULTS@#Among 910 HSCT patients, 111 patients were diagnosed as BSI within 100 days after transplantation, and 98 patients showed BSI during the period of agranulocytosis. Multivariate analysis showed that the usage of anti-thymocyte globulin (ATG), long duration of agranulocytosis and low infusion volume of mononuclear cell (MNC) were the independent risk factors affecting BSI after HSCT. Among 121 pathogenic bacteria isolated, 76 Gram-negative (G-) bacteria (62.8%), 40 Gram-positive (G+) bacteria (33.0%), and 5 fungi (4.1%) were detected out. The top three pathogens were Escherichia coli, Staphylococcus epidermidis and Pseudomonas aeruginosa. The drug-resistance rates of Escherichia coli and Klebsiella pneumoniae to carbapenems was 14.3% and 7.7%, respectively, and Pseudomonas aeruginosa was 66.7%. The susceptibility of G+ bacteria to vancomycin, linezolid and teicoplanin was 97.5%, 100% and 100%, respectively. The crude mortality rate of the patients with BSI at 100 days after HSCT was significantly higher than that of patients without BSI (P<0.001).@*CONCLUSION@#The usage of ATG, long duration of agranulocytosis and low infusion volume of MNC are independent risk factors for BSI after HSCT. The pathogens after HSCT are mainly G- bacteria. Pseudomonas aeruginosa is highly resistant to carbapenems. Key words　　;

Clinical and Bacteriological Analysis of Bacterial Bloodstream Infections in Patients with Acute Leukemial / 中国实验血液学杂志

OBJECTIVE@#To investigate the clinical characteristics, etiology and drug susceptibility of bacterial bloodstream infections in acute leukemia(AL) patients.@*METHODS@#Clinical data, etiology and drug susceptibility of acute leukemia patients with bacterial bloodstream infections from April 2009 to April 2018 were retrospectively analyzed.@*RESULTS@#A total of 376 strains were isolated, 76.9% was Gram-negative bacterial and 23.1% was Gram-positive bacteria. Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumoniae were listed as the top three of Gram-negative bacteria. The susceptibility of Escherichia coli to the tigacycline, imipenem and meropenem was 100.0%, 98.2% and 98.1%, respectively. The susceptibility of Klebsiella pneumoniae to the tigacycline, imipenem and meropenem were 100.0%, 98.3% and 94.4%, respectively. The adjustment rate for initial use of carbopenems was 3.8%, while the adjustment rate for initial use of noncarbopenems was 74.3% in patients with main Gram-negative bacterial blood stream infection. The susceptibility of Gram-positive bacteria to glycopeptide antibiotics, linezolid and tigacycline was 100.0%.@*CONCLUSION@#Gram-negative bacteria is the majority type of bacteria in AL patients with bacteria blood stream infections. The susceptibility of Gram-negative bacteria to the carbapenems is high, and the treatment adjustment rate is obviously low. The glycopeptide, linezolid and tigacycline are effective for Gram-positive bacteria infections..

Clinical analysis of autoimmune hemolytic anemia after allogeneic hematopoietic stem cell transplantation in thalassemia major / 中华血液学杂志

Objective: To explore the diagnosis, treatment and prognosis of autoimmune hemolytic anemia (AIHA) after allo-HSCT in patients with thalassemia major (TM). Methods: A retrospective analysis of AIHA status after allo-HSCT in 291 TM patients from July 2007 to December 2017 was conducted. Results: Five of the 291 TM patients (1.72%) were diagnosed with post-transplant AIHA. The median time of AIHA was 7 (5-12) months after HSCT. All post-transplant AIHA patients were positive in direct and indirect Coombs test, the main clinical manifestations were dizziness, fatigue, pale complexion, skin and sclera yellow, and soy sauce urine. The incidence of AIHA was higher after unrelated donor transplantation (6.36%, 4/63) compared with that of sibling donor transplantation (0.43%, 1/228). One patient who received only prednison was dead. Four patients who received rituximab combined with prednisolone were alive, Coombs test in two of them were negative. Conclusions: AIHA after allo-HSCT developed in 1.72% patients with TM. Monitoring of Coombs test was important for diagnosis of post-transplant AIHA. The incidence of post-transplant AIHA was higher in unrelated donors compared with that of sibling donors transplantation. Treatment of rituximab combined glucocorticoid was effective strategy for post-transplant AIHA.

Real-time quantitative PCR detecting B7-H1 gene expression in leukemia cells and its clinical implications / 中华血液学杂志

<p><b>OBJECTIVE</b>To detect the expression of B7-H1 gene in bone marrow mononuclear cells (BMMNCs) from leukemia patients and explore its clinical implications.</p><p><b>METHODS</b>The B7-H1 mRNA expression levels of BMMNCs from 74 newly diagnosed leukemia patients and 10 normal volunteers were detected by real-time quantitative PCR. At the same time, BMMNCs from 12 patients in complete remission (CR) after chemotherapy and 5 in relapse were followed up. The correlation between the clinical features of 74 de novo leukemia patients and the expression level of B7-H1 gene was analyzed.</p><p><b>RESULTS</b>The mRNA expression level of B7-H1 gene in BMMNCs from de novo leukemia patients (RQ = 0.125) was lower than that from normal control (RQ=1). When patients achieved CR the gene expression level (RQ = 69.07) was significantly higher than that before CR (P = 0.001). After relapsed, its level (RQ=4) was still higher than that before CR (P > 0.05). No clinical parameters such as gender, age, peripheral white blood count, blast cells ratio in BM, CD34 positive cells were significantly correlated with the expression level of B7-H1 except the response to therapy. The initial expression level of B7-H1 gene in non CR patients after therapy was significantly higher than that in CR patients (RQ = 26. 91, P = 0.005).</p><p><b>CONCLUSION</b>The mRNA expression level of B7-H1 gene in newly diagnosed leukemia patients is lower than that in normal controls, and is higher in CR patients than in newly diagnosed patients. There is a correlation between the gene expression level and responsiveness to therapy.</p>

The role of stromal cell-derived factor and its receptor-CXCR4 in G-CSF-induced hematopoietic stem cell mobilization / 中华血液学杂志

<p><b>OBJECTIVE</b>To explore the role of stromal cell-derived factor (SDF-1) and its specific receptor CXCR4 in the G-CSF-induced hematopoietic stem/progenitor cells (HSPCs) mobilization in human healthy donor.</p><p><b>METHODS</b>The changes of SDF-1/CXCR4 in bone marrow (BM) and peripheral blood (PB) of healthy donors during G-CSF-induced mobilization were detected by enzyme-linked immunosorbent assay (ELISA), immunohistological staining and flow cytometry. SDF-1 neutralizing antibody wes injected into BALB/c mice to further test its effect on mobilization.</p><p><b>RESULTS</b>SDF-1 concentration in mobilized BM (mBM), steady state BM (ssBM) and PB were(7.23 +/- 0.66) microg/L, (5.43 +/- 0.35) microg/L and (5.42 +/- 0.52) microg/L, respectively. SDF-1 protein levels were decreased in the BM (P < 0.05) after 5-day G-CSF injection, and its concentration gradient between BM and PB disappeared (P > 0.05). Significant up-regulation of CXCR4 expression was observed on mBM CD34 cells in healthy donors. The rate of CXCR4 expression on CD34 cells in ssBM, mBM and mobilized PB were (40.98 +/- 21.56)%, (65.80 +/- 24.68)% and (27.54 +/- 26.03)%, respectively. Comparing with that in ssBM and mBM, CXCR4 expression on mobilized PB CD34+ cells were significantly decreased (P < 0.05). Inhibition of SDF-1 signal by blocking monoclonal antibodies significantly reduced G-CSF-induced mobilization in BALB/c mice. This resulted in significant decrease of white blood cell count and progenitors mobilized into peripheral circulation.</p><p><b>CONCLUSION</b>G-CSF induces HSPCs mobilization by decreasing bone marrow SDF-1 and down-regulating CXCR4 expression on HSPCs.</p>

Retrospective analysis of 54 patients with high risk aggressive T-cell non-Hodgkin lymphomas / 中华血液学杂志

<p><b>OBJECTIVE</b>To analyse the clinical characteristics, treatments and prognosis of patients with T-cell non-Hodgkins lymphoma (NHL) in intermediate-high and high risk.</p><p><b>METHODS</b>Fifty-four patients with T-cell NHL classified intermediate-high and high risk were retrospectively analyzed.</p><p><b>RESULTS</b>According to WHO classification criteria, there were 12 cases of T-lymphoblastic lymphoma (TLBL), 31 peripheral T-cell lymphoma unspecified (PTCL-U), and 11 hepatosplenic T-cell lymphoma (HSTCL). The IPI were 12 cases of intermediate-high risk and 42 high risk. Of them, 49 cases were bone marrow affected and 7 CNS affected. The response rate (RR) for the whole group was 86.5%, complete remission (CR) rate 67.3%, and 3-year survival rate 16.0%. The 3-year survival rates for haematopoietic stem cell transplantation and chemotherapy groups were 44.4% and 8.3%, respectively. Multi-factor analysis showed that choice of therapy modality, and achievement of remission were significant factors for overall survival.</p><p><b>CONCLUSION</b>T-NHL is a group of heterogeneous malignancies. The response rate of intermediate-high and high risk T- NHL, especially PTCL-U and LTBL, is not low, but its long-term outcome is poor. New treatment modality needs to be explored for these patients, and autologous HSCT is perhaps a good choice.</p>

Progress in Neural Differentiation of Umbilical Cord Blood -Derived Stem Cells / 中国生物工程杂志

The ability of repair and regeneration of central nervous system (CNS) is limited. So many researchers applied themselves to search a valuable cell resource for treating severe diseases of the CNS. Several studies from different laboratories have recently reported that stem cells derived from human umbilical cord blood under certain in vitro conditions can manifest neural features that resemble features of neural-derived cells. In vivo transplantation studies have shown that these stem cells persistently engraft in the CNS, some engrafted cells acquire the characteristics of neurons and glia, and improve functional recovery after central nervous system injury. The existence of stem/progenitor cells with previously unappreciated proliferation and differentiation potential in umbilical cord blood raise the possibility that cord blood may provide an efficient source of cells differentiating into the neural lineage, with a potential to be employed in the therapy of human CNS diseases. The achievement and focuses on the mechanisms and modulation of induction of differentiation and in vitro and in vivo studies in this field was reviewed.

Long-term survival analysis in 170 cases of acute promyelocytic leukemia / 中国实验血液学杂志

This study was aimed to investigate various factors influencing long-term survival in patients with acute promyelocytic leukemia. A single institutional retrospective study with long-term follow-up was performed to better define the prognostic factors and a rationale for the use of ATRA, chemotherapy, and As(2)O(3) in the treatment of newly diagnosed APL patients. Newly diagnosed patients with APL entering complete remission (CR) were followed up for 6 to 185 months (n = 170) from January 1990 to December 2004. Univariate and multivariate analysis of 8 potential factors influencing survival and prognosis were carried out with Log-Rank and Cox regression method, including sex, age, initial WBC count, the level of lactic hydrogenase (LDH), first induction regimen, time from induction therapy to CR, post-remission therapy, negative or positive rate of PML-RAR alpha and follow-up of reverse transcription-polymerase chain reaction (RT-PCR). The results showed that the estimated 5-year overall survival (OS) and relapse-free survival (RFS) were 80.9% +/- 4.0% and 71.0% +/- 4.0% respectively. The 23 patients relapsed at the median time of 15 months (6 - 70) after CR. Univariate analysis revealed that initial WBC count, first induction regimen, time from induction therapy to CR, type of post-remission therapy and persistent negative RT-PCR in remission were important prognostic factors for long-term survival. Multivariate study demonstrated that only type of post-remission therapy was associated with RFS and OS. It is concluded that the post-remission treatment combining ATRA, As(2)O(3) and chemotherapy would significantly improve the long-term survival of APL patients entering CR(1).

Related factors affecting the isolation of multipotent non-hematopoietic adult stem cells from umbilical cord blood / 中国实验血液学杂志

To investigate the related factors affecting the isolation of multipotent non-hematopoietic adult stem cells (MNASCs) from human umbilical cord blood in low serum (2%) condition, the isolation conditions were optimized and the yield of MNASCs was improved. MNASCs from human umbilical cord blood samples were isolated, and the effects of medium component, medium exchange time and initial plating density for isolation of MNASCs were studied. Then, the MNASCs were isolated and cultured in optimal condition, the surface antigen expression and differentiation potential of MNASCs were detected. The result showed that the medium of DMEM/F12 was better than IMDM and DMEM-LG for MNASCs culture in low serum condition. The optimal yield of MNASCs was obtained when mononuclear cells were cultured at a initial plating density of 1 x 10(6) cells/cm2 and the medium was exchanged to remove the nonadherent cells after 72 hours of inoculation. MNASCs isolated and cultured under the above-mentioned conditions maintained a homogenous morphology, high potential ability of expansion and differentiation. It is concluded that culture conditions with low serum defined in this study is optimal for the successful isolation and expansion of umbilical cord blood MNASCs with high numbers for subsequent cellular therapeutic approaches.

Comparison of expanding dendritic cells derived from cord blood and mobilized peripheral blood by two-step culture method / 中国实验血液学杂志

To compare the expansion efficiency and function of dendritic cells derived from CB-CD34+ cells and MPB-CD34+ cells by using two-step culture method, enriched CB-CD34+ cells or MPB-CD34+ cells with immunoadsorption were primarily cultured in the presence of FL, SCF, TPO, GM-CSF for 10 days, and then further cultured with a combination of GM-CSF, IL-4, TNF-alpha, CD40Ab and PGE2 to induce DC. The DC phenotypes were detected by flow cytometry, the expansion efficiency and cell function were evaluated by mix-lymphocyte reaction (MLR), IL-12 level was detected by using ELISA and the chemotactic function mediated by secondary lymphoid tissue chemokine (SLC) was determined with Transwell plate. The results indicated that after 10 days of expansion, there were no significant difference in the percentage of CD14+CD1a- cells between CB and MPB [(40.48 +/- 16.85)% vs (28.07 +/- 23.19)%, P > 0.05], but the expansion of total cells in CB was higher than that in MPB (388.88 +/- 84.63-fold vs 79.67 +/- 10.32-fold, P < 0.01), so the yield of CD14+CD1a- cells from CB was significantly higher than that from MPB too (189.42 +/- 25.02-fold vs 28.74 +/- 23.27-fold, P < 0.01). The percentage of CD83+ DCs cultured with CD40Ab/PGE2 derived from CB were higher than those cultured with TNF-alpha derived from MPB respectively [(34.52 +/- 11.22)% vs (3.70 +/- 2.27)% and (36.69 +/- 13.36)% vs (7.34 +/- 3.364)% respectively, P < 0.01]. In the same circumstance, the yield of CD83+ DCs derived from CB was much more than that from MPB (198.72 +/- 117.53 times vs 33.95 +/- 6.19 times, P < 0.01). There were no difference in stimulating capacity, IL-12 secretion and migration capacity between DCs derived from CB and MPB. It is concluded that DCs induced from CB-CD34+ cells by two-step culture possess similar functions with that from MPB-CD34+ cells, but the yield of DCs from CB CD34+ cells is much more than that from MPB CD34+ cells.

Effects of stromal cell-derived factor 1 and platelet factor 4 on the adhesion characteristics and chemotactic function of ex vivo expanded umbilical cord blood CD34+ cells / 中国实验血液学杂志

To investigate the effects of stromal cell-derived factor 1 (SDF-1) and platelet factor 4 (PF4) on the homing-related function of expanded ex vivo umbilical cord blood CD34(+) cells, purified cord blood CD34(+) cells were cultured in serum-free medium containing a HGF combination of FL + SCF + TPO (FST) with either 100 ng/ml SDF-1 alone, 100 ng/ml PF4 alone, or both of these 2 cytokines. The expansion rate of CD34(+) cells, colony formation, homing-related functions including expression of homing-related adhesion molecules of expanded CD34(+) cell, adhesion activity and chemotactic function of the re-selected expanded CD34(+) cells were evaluated at different time points. The results showed that expansion rate of CD34(+) cells and expansion multiple of CFU in SDF-1 groups were higher than those in control. The expression of CD49e on the expanded CD34(+) cells was remarkable up-regulated, in contrast, expression of CXCR-4 on the expanded CD34(+) cells was remarkable down-regulated in SDF-1 groups. The expression of CD49e, CD54 and CXCR-4 on the expanded CD34(+) cells were remarkably up-regulated in the PF4 groups. In all the SDF-1 group, PF4 group and SDF-1 plus PF4 group, the ability of expanded CD34(+) cells adhering to fibronectin layer were higher than those in the control on day 10. Spontaneous migration rate of expanded CD34(+) cells in SDF-1 groups were higher than those in control, while SDF-1-induced migration rate were lower than those in control on day 10. SDF-1-induced migration rate in PF4 groups were higher than those in control on day 10. Spontaneous and SDF-1-induced migration rate of expanded CD34(+) cells in the SDF-1 plus PF4 groups were higher than those in control on day 10. It is concluded that, SDF-1 and PF4 can up-regulate expression of adhesion molecules on expanded CD34(+) cells, and retain the adherent and migration ability of expanded CD34(+) cells, which is helpful for the homing of expanded CD34(+) cells. In short, SDF-1 and PF4 are helpful for the homing-related function of the expanded UCB HSPC.